NYSGA 1980
Field Studies of
New Jersey Geology
And Guide to Field Trips:
52nd Annual Meeting of the New York State Geological Association
1980
Warren Manspeiser, Editor
Field trips are numbered as follows:
GEOLOGIC TRAVERSE:
GEORGE WASHINGTON BRIDGE TO THE DELAWARE WATER GAP
1.Triassic and Jurassic Formations of the Newark Basin
Paul E. Olsen
2. PreCambrian Rocks of the New Jersey Highlands
John H. Puffer
3. Lower Paleozoic Carbonates: Great Valley
Frank J. Markewicz and Richard Dalton
4. Geology of the Ridge and Valley Province, Northwestern New Jersey and Eastern Pennsylvania
Jack B. Epstein
FOLD BELT
5. Alleghanian Thrust Faults in the Kittatinny Valley, New Jersey
Avery A. Drake Jr. and Peter T. Lyttle
COASTAL PLAIN
6. The New Jersey Coastal Plain and its Relationship with the Baltimore Canyon Trough
Richard K. Olsson
7. Coastal Dynamics and Environments on Sandy Hook, New Jersey
Norbert P. Psuty, Lindsay Nakashima, and George Theokritoff
8. Landscape Features and Bog Iron Ore Deposits of the New Jersey Pine Barrens
Emily W.B. Russel and Edward Krug
GLACIATION
9. Late Wisconsin-Holocene History of the Lower Hudson Region: New Evidence from the Hackensack and Hudson River Valleys
Stephen. P. Averill, Richard R. Pardi, Walter S. Newman, and Robert J. Dineeli
ECONOMIC GEOLOGY
10. Economic Geology: New Jersey Highlands General Introduction and Road Log
Andreas H. Vassiliou
Uranium and Rare Earth Mineralization at the Bemco Mine Near Cranberry Lake, New Jersey
Iron Ore Deposits of the New Jersey Highlands
The Geologic Setting of the Sterling Hill Zinc-Iron-Manganese Deposit
Bob Metsger
ENVIRONMENTAL GEOLOGY
11. Environmental Geology: Hackensack Meadowlands
Sam L. Agron
12. Environmental Geologic Traverse.
Joseph A. Fischer
13. The Passaic River Flood Plain and Basin in New Jersey: Problems of Encroachment
Joseph S. Weisberg and John Marchisin
RIFT BASIN
14. Late Triassic Part of Newark Supergroup, Delaware River Section, West Central New Jersey
F.B. Van Houten
15. Brittle Faults (Ramapo Fault) and Phyllonitic Ductile Shear Zone in the Basement Rocks of the Ramapo Seismic Zone, New York
and New Jersey, and Their Relationship to Current Seismicity
Nicholas M. Ratcliffe
16. Rift Tectonics Inferred from Volcanic and Clastic Structures
Warren Manspeizer
17. Fossil Great Lakes of the Newark Supergroup in New Jersey

1: TRIASSIC AND JURASSIC FORMATIONS OF THE NEWARK BASIN
PAUL E. OLSEN
Bingham Laboratories, Department of Biology
Yale University, New Haven, Connecticut
Abstract
Newark Supergroup deposits of the Newark Basin (New York, New Jersey and Pennsylvania) are divided into nine formations called (from bottom up): Stockton Formation (maximum 1800 m); Lockatong Formation (maximum 1150 m); Passaic Formation (maximum 6000 m); Orange Mountain Basalt (maximum 200 m); Feltville Formation (maximum 600 m); Preakness Basalt (maximum + 300 m); Towaco Formation (maximum 340 m); Hook Mountain Basalt (maximum 110 m); and Boonton Formation (maximum + 500 m). Each formation is characterized by its own suite of rock types, the differences being especially obvious in the number, thickness, and nature of their gray and black sedimentary cycles (or lack thereof).
Fossils are abundant in the sedimentary formations of the Newark Basin and provide a means of correlating the sequence with other early Mesozoic areas. The Stockton, Lockatong, and most of the Passaic Formation are Late Triassic (?Middle and Late Carnian-Rhaetic) while the uppermost Passaic Formation (at least locally) and younger beds appear to be Early Jurassic (Hettangian and Sinemurian) in age. The distribution of kinds of fossils is intimately related to sequences of rock types in sedimentary cycles.
INTRODUCTION
Far from being the consequence of the last gasps of the Appalachian Orogeny, Late Triassic and Early Jurassic Newark Supergroup basins formed in dynamic association with the opening of the Atlantic Ocean (Sanders, 1974; Van Houten 1977; Manspeizer, Puffer, and Cousminer, 1978; Olsen, 1978). In addition, Newark Supergroup rocks, once thought to be nearly barren of fossils, are now known to be exceptionally rich in organic remains (Thomson, 1979), replete with plants, invertebrates, and vertebrates spanning some 35 million years of the Early Mesozoic (Cornet, 1977). Finally, long episodes of unusually continuous deposition coupled with an abundance of laterally extensive stratigraphic "marker" beds (McLaughin, 1946), makes this deposit ideal for studying time-facies relationships and evolutionary phenomena. These recent discoveries have focused new interest on Newark strata.
The Newark Basin (Fig. 1 and 2) is the largest of the exposed divisions of the Newark Supergroup, covering about 7770 km2 and stretching 220 km along its long axis. The basin contains the thickest sedimentary sequence of any exposed Newark Supergroup basin and correspondingly covers the greatest continuous amount of time. Thus, the Newark Basin occupies a central position in the study of the Newark Supergroup as a whole.
In well over a century of study the strata of Newark Basin have received a relatively large amount of attention. By 1840, the basic map relations were worked out (Rogers, 1839, 1840, Cook, 1868) and by 1898, the major rock-stratigraphic subdivisions of the basin section were delimited and named (Darton, 1890; Kummel, 1897, 1898). Despite this long tradition, fundamental aspects of its historical and structural geology have remained essentially unexplored. The lithostratigraphy of the younger sediments, in particular, has received short shrift. Recently I have revised certain aspects of Newark Basin stratigraphy with an emphasis on the younger rocks (Olsen, in press). In the process I have proposed a number of new formational names (Table 2). Here I will review the formations of the Newark Basin and attempt to place their broader lithostratigraphic features into biostratigraphic context.

1: TRIASSIC AND JURASSIC FORMATIONS OF THE NEWARK BASIN

Begin Trip
To the east about one mile is the west portal of the George Washington Bridge, Fort Lee, New Jersey. The west abutments of the bridge rest on Stockton and Lockatong formations and Palisade Diabase. Roads along the east face of the Palisade Escarpment in the Fort Lee portion of Palisades Interstate Park have excellent exposures of nine individual detrital cycles of the lower Lockatong, each of which has been traced 15 km to the south (Olsen, this 1.7 Fieldbook). Three of these cycles are especially fossiliferous; the lowest of these (called cycle 6) has produced articulated remains of Semionotus brauni and disarticulated remains of the little reptile Tanytrochelos. The middle fossiliferous cycle (cycle 5) contains abundant disarticulated remains of Diplurus newarki and articulated remains of Turseodus. The upper cycle (cycle 2) has produced abundant articulated Turseodus and disarticulated large Diplurus. Clam shrimp (conchastracans) and ostracods are also common in cycles 5 and 2. These and other Lockatong cycles exposed here were deposited in shallower water than their more southern extensions.
In this area the trigonometrically computed thickness of both the Stockton Formation and the Lockatong Formation is less than 200 m. This is almost an order of magnitude thinner than the same formations along the Delaware River (Van Houten, this Fieldbook). While part of this thinning is due to the lateral replacement of Lockatong facies by Passaic Formation, most of the thinning is due to the thinning of individual cycles of the Lockatong Formation and thinning of the whole of the Stockton.
Numerous small, predominantly normal, faults striking north and northeast and down-dropping to the east characterize this portion of the Newark Basin. The reentrant in the Palisade Escarpment just south of here is an erosional result of some of the larger of these faults.

Cross large normal fault.
Crossing large normal fault cutting the Palisade Diabase and overlying the Lockatong Formation. This fault nearly doubles the outcrop width of the Palisade Diabase in this area. Just north of here the upper contact of the sill and the Lockatong is duplicated by this fault.
In marked contrast to faults is the northwestern portion of the Newark Basin, many of which have slickensides showing lateral (both sinistral and dextral) movement, those examined to date in the area along the Palisades show only vertical slickensides (both those dropping down to the east and to the west) (personal observation and Manspeizer, pers. comm.).

Lockatong-Palisade Sill contact
Excellent outcrops of the Lockatong-Palisade Sill contact and overlying detrital cycles of the Lockatong. Here the upper surface of the Palisade Sill is smoothly concordant with the Lockatong. I believe the cycles exposed here tie in with those exposed in Granton Quarry to the south, although it is far from certain. Articulated Turseodus and conchostracans, at least, are common at this outcrop.
According to Van Houten (1969), these Lockatong hornfels include grossularite-andradite, prehnite. and diopside varieties.

Stockton Formation
Hill at this point is underlain by a tongue of Stockton Formation (Van Houten, 1969). Presumably this is the same unit exposed about 1 km. north of Granton Quarry. There good exposures reveal Stockton Formation with a thin bed of Synorichthys -bearing green and gray siltstone with overlying beds of gray-buff arkose containing what I interpret as very well-developed limestone caliche paleosols. Tongues of Stockton such as this may correspond to clusters of chemical cycles prevalent in similar positions in the central Newark Basin.

Approximate contact with Passaic Formation.
Lowermost Passaic is very poorly exposed in the vicinity of Ridgefield and consists of mottled red-buff feldspathic sandstone and red siltstone.

Hackensack Meadows.
Broad belt of relatively soft red siltstone and minor gray siltstone and arkose correlating with upper Lockatong and lower Passaic Formation of Delaware River area (Van Houten, this Fieldbook).

Section A of Passaic type section begins here
Beginning of the type section of the Passaic Formation (see Table 2, fig. 4. this paper) (Olsen, In Press). The type section of the Passaic consists of intermittent exposures along Route 80. These exposures show interbedded red feldspathic sandstone and siltstone with small-to-large-scale cross-bedding, abundant bioturbation structures (including roots and Scoyenia) and some beds of caliche. Section A (fig. 4) of the type section begins here.
2011: Much of the outcrop has been obscured by sound barriers, probably constructed after 1980.

Section B of the type section of the Passaic Formation.
2011: Much of the outcrop has been obscured by sound barriers, probably constructed after 1980.

Section C of the type section of the Passaic Formation.

Section D of the type section of the Passaic Formation.

Garrett Mountain on Left, Passaic Falls on Right
Garrett Mountain is visible on left (south), Passaic Falls is on the right (north). The upper Passaic Formation of Rhaetic age (latest Triassic) has produced near here a series of well preserved skeletons of the highly specialized procolophonid reptile Hypsognathus (Colbert, 1946). About one skeleton or skull is found per decade.
Just south of this point, along Route 20 are exposures of Passaic Formation red conglomerates. The frequency of beds such as these increase to the northeast and decrease to the southwest. These conglomerate beds are crucial to tests of the "Broad Terrain Hypothesis" (Sanders, 1963, 1974). Cross beds consistently yield paleocurrent directions indicating transport from northeast to southwest (personal observation and Manspeizer, pers. comm.) in line with the mean paleocurrent vector for this portion of the Passaic Formation. Clasts consist primarily of Paleozoic sedimentary rocks, including quartzite, quartzite conglomerate, limestone, and minor phyllite. Such rocks are not known to be present to the east of the Newark Basin. Clast composition is very similar to beds found in the northernmost part of the Newark Basin, beds thought to have a northwestern provenance. The clasts are very different from those of the contemporary New Haven Arkose of the Hartford Basin. The "Broad Terrain
Hypothesis" predicts that these beds of the Passaic should be western equivalents of the New Haven Arkose. Two alternative explanations come to mind.
1. The provenance of these Passaic conglomerates was to the east of the Newark Basin; presumably these source rocks are completely eroded. Either the Newark and Hartford Basins were with the Paleozoic sedimentary rocks intervening or the Paleozoic rocks were exposed to the east of a southern continuation of the Hartford Basin and contributed to New Haven Arkose bed no longer exposed.
2. The provenance of these Passaic conglomerates was to the west or north but the sediments were redeposited by southwest moving streams.
Detailed studies of these conglomerates are clearly needed.

Contact of Passaic Formation with overlying Orange Mountain Basalt
Contact of Passaic Formation with overlying Orange Mountain Basalt on left (south). This is section E of the type section of the Passaic Formation (fig. 7). A series of faults cut the ridge made up of Orange Mountain Basalt here; some of these faults are visible in the cut on the left, just west of the Passaic-Orange Mountain contact.
Uppermost few meters of Passaic Formation, exposed to the south of here (Montclair State College) has produced a reptile footprint assemblage consisting of a mixture of taxa common to older beds of the Passaic and younger beds of the Feltville, Towaco, and Boonton Formations. The oldest North American occurrences of Batrachopus, and grullatorid footprints of the Anchisauripus minuscolus- type have been discovered at this locality (Olsen and Galton, 1977).
This assemblage is nearly identical to a suite of footprints found in the Rhaeto-Liassic of France. It is unclear whether these uppermost Passaic beds are latest Triassic or earliest Jurassic (the French workers are unsure of their footprint bearing beds, as well); The Triassic-Jurassic boundary probably lies within a few meters of the Orange Mountain in the Route 80 area.

Exposures of Orange Mountain Basalt.
Upper flow units of Orange Mountain Basalt are exposed in quarries near here. A diverse suite of zeolite minerals has made some of these quarries famous (Manspeizer, this Fieldbook; Van Houten, 1969).

Crossing the Passaic River
Crossing the Passaic River, which here follows the Feltville-Orange Mountain Basalt contact.
The Feltville Formation is very poorly exposed in this area; the lower Feltville is not exposed at all. Exposures in bluffs just north and south of here consist of gray and buff arkose and sandstone, often cross-bedded and containing coalified plant remains, and red feldspathic siltstone and sandstone with roots and reptile footprints.

Position of Preakness Basalt: not exposed.
A confluence of a series of faults, densely spaced joint systems, and the low dip of the bedding are probably responsible for the low profile of the Preakness Basalt in this area. The outcrops of the main lower flow in this area (such as along Route 46 to the south) show the flow's characteristic splintery joint pattern.

Approximate position of Preakness Basalt - Towaco Formation contact.
The large outcrop width of Towaco Formation here is due to the Hook Mountain Anticline. Toward the west, along the axis of the anticline, the dip of the Towaco Formation steadily decreases.

Reptile footprints to North
About 4.4 miles north is the abandoned Vreeland Quarry which produced the superb reptile footprints on display at the Rutgers University Geological Museum. Just to the northeast is Tom's Point, an area which produced hundreds of reptile footprints in the 1960's. Exposures still extant include much of the non-red portion of the second-from-the-top Towaco Formation cycle. Exposures of the upper two Towaco Formation cycles occur sporadically in surrounding areas.

Type section of Hook Mountain Basalt.
Two flows and the contact between them are exposed along the highway (fig. 11). The entablature and lower colonnade of the lower flow are exposed on Hook Mountain Road just north of the Route 80 overpass.

Approximate position of Boonton-Hook Mountain Basalt contact.

The Boonton Formation is not exposed along Route 80.
The Boonton Formation is not exposed along Route 80 but 2 miles to the north are the excellent exposures along the Rockaway River (fig. 12). These exposures begin at the dam at the north end of Boonton (Jersey City) Reservoir and extend for over 1 mile along the river bluffs. The dam footing rests on the Boonton Fish Bed which during the 1800's and early 1900's produced thousands of fish of the "Semionotus elegans group," Redfieldius spp., several specimens of the large coelacanth Diplurus longicaudadus, and a single specimen of Ptycholepis.
Only the underlying beds are exposed now, by these beds produce abundant plant remains and reptile footprints.

Approximate position of the Ramapo Fault: end of the Newark Basin.
A prominent bluff of metamorphics marks the west wall of the fault (see Ratcliffe, this Fieldbook).

2: PRECAMBRIAN ROCKS OF THE
NEW JERSEY HIGHLANDS
JOHN H. PUFFER
Department of Geological Sciences
Rutgers University Newark, New Jersey
INTRODUCTION
Rocks exposed along Route 15 offer an excellent opportunity to observe most of the major metamorphic and igneous units that make up the New Jersey Highlands (Fig. 1). Rock is exposed along almost the entire twenty kilometers of Route 15 that traverse the strike of the rock units. The purpose of this field guide is to describe the rock units exposed along Route 15 and to report on the current status of recent efforts aimed at understanding the metamorphic and igneous environments that formed the rocks,
Most early descriptions of the New Jersey Highlands subdivide the Precambrian into four major units: These four units appear on the legend of Lewis and Kummel's (1910-1912) Geologic Map of New Jersey as:
1. Byram Gneiss "Gray granitoid gneiss composed of microcline, micro-perthite, quartz, hornblende or pyroxene, and sometimes mica".
2. Losee Gneiss "White granitoid gneiss composed of oligoclase, quartz, and occasionally orthoclase, pyroxene, hornblende, and biotite".
3. Pochuck Gneiss "Dark granular gneiss composed of pyroxene, hornblende, oligoclase, and magnetite".
4. Franklin Limestone "Coarse white marble..."
More recent works by Hotz (1952), Sims (1958), Drake (1969), Smith. (1969), and Baker and Buddington (1970) have subdivided the Byram Gneiss into a "Hornblende Granite" and a "Pyroxene Granite" and a few minor units; have substituted rock names such as "Quartz-Oligoclase Gneiss" and. "Hypersthene-Quartz-Oligoclase Gneiss" for portions of the Losee Gneiss; have subdivided the Pochuck Gneiss into "Amphibolite" and "Pyroxene Gneiss"; and have recognized several additional rock units such as "Quartz-Potassium Feldspar Gneiss and "Syenite Gneiss". Widmer (1964) has recognized twenty-four mappable Precambrian rock units in the New Jersey Highlands including marble, quartzite, skarn, pegmatite, quartz diorite, four kinds of granite, and fifteen kinds of gneiss. Because of the general reconnaissance nature of this field trip only the major units among the complex assortment of Highlands rock types will be described in this report.

2: PRECAMBRIAN ROCKS OF THE
NEW JERSEY HIGHLANDS

STOP 1. Hornblende Granite (sample 0.9, Table 3).
Exit at the Picatinny Arsenal. The rock exposed along the hill to the right is Hornblende Granite. Exercise extreme caution when crossing the road to examine the granite. The granite here is quite homogeneous but on the other side of the hill contains less hornblende and becomes an alaskite. Note the well developed foliation.

Green Pond Fault.

Green Pond Conglomerate
Green Pond Conglomerate; silurian correlative of Shawangunk Conglomerate. Most of the pebbles are rounded milky quartz.

Very complex mixture of Pyroxene Granite
Very complex mixture of Pyroxene Granite near the south
end of the roadcut (sample 3.6, Table 3). Quartz-Oligoclase Gneiss near the center, and Hornblende Granite near the north end (4.0 mile on log). Several disconnected xenoliths of amphibolite may be observed in the granite as well as numerous granite pegmatites emplaced parallel to the foliation of the granite.

Amphibolite (sample 4.3, Table 3).

Fine grained quartz monzonite alaskite and Amphibolite
Fine grained quartz monzonite alaskite along end of roadcut; Amphibolite along the north end.

Pyroxene Granite (sample 5.9, Table 3).

STOP 2. Pyroxene Granite.
Note the wide ranging quartz content, dark color, and well developed foliation. The pyroxene component of the rock here is deeply altered; the feldspar component ranges from a plagioclase rich perthite (as in sample 5.9, Table 3) to a K-spar rich antiperthite (as in sample 6.6, Table 3). Busses will park on breakdown lane. Watch out for loose rock on vertical face of road cut.

Pyroxene Gneiss
Pyroxene Gneiss composed of approximately 50 percent antiperthite, 10 percent plagioclase, 15 percent quartz, 20 percent pyroxene-amphibole intergrowths, and 5 percent opaque oxides.

Pyroxene Granite

Pyroxene Syenite (sample 8.2, Table 3).

Pyroxene Granite
Pyroxene Granite including bands of syenite and various gneisses that have a similar general appearance but dissimilar mineralogies making up a virtually unmappable complex for 0.3 mile. Amphibolite bands are also found here.

STOP 3. Syenite Gneiss (sample 8.7, Table 3).

STOP 4. Quartz-Oligoclase Gneiss, (samples 9.1a and b, Table 3).
STOP 4. Quartz-Oligoclase Gneiss, (samples 9.1a and b, Table 3). Both white and pink varieties of Quartz-Oligoclase Gneiss occur here. Most of the rock here contains less biotite and is less foliated and banded than more typical Quartz-Oligoclase Gneiss. Amphibolite schliern are common. Busses park on abandoned entrance road to Route 15.

Amphibolite.

Quartz-Oligoclase Gneiss

Amphibolite

Hornblende Granite.
Hornblende Granite. Alternating plagioclase rich and
K-spar rich bands make this rock less homogeneous than
the granite at STOP 1.

Kittatinny Limestone. Cambro-Ordovician dolomitic limestone.

Hornblende Granite

Granodiorite Gneiss.
Highly foliated rock composed of 40 percent plagioclase, 30 percent quartz, 20 percent K-Spar, and 10 percent biotite.

STOP S. Franklin Marble.
The marble is intruded by granite pegmatites. If traffic is heavy it may be necessary to skip this stop. The road shoulder is quite narrow.

3: LOWER PALEOZOIC CARBONATES:
GREAT VALLEY
Frank J. Markewicz and Richard Dalton
New Jersey Department of Environmental Protection
Division of Water Resources, Trenton, New Jersey
INTRODUCTION
The purpose of this field trip is to demonstrate the subdivision of the Cambro-Ordovician carbonate sequence as proposed by the field trip leaders. In addition, there will be discussions on environmental, hydrogeologic, and engineering problems in these carbonates and how this subdivision has "opened the doors" in understanding how everyday problems from man's activities can affect or be affected by certain lithic units within the carbonate sequence. This understanding of the interaction between man's activities and how it might affect or be affected by critical aquifers, thin or thick soil horizons, and specific lithologies by septic waste loads, ground water pollution, building foundation loading, landfills, etc., has become extremely important in the land development process.
We anticipate this field trip will not only relate the carbonate subdivision but will point out how important this breakdown is to applied geology.

3: LOWER PALEOZOIC CARBONATES:
GREAT VALLEY

STOP 1. Limeport member of the Allentown Formation.
Geologic Setting
Although less than 20 feet is exposed here it contains many of the sedimentary features found in the member.
In the Pequest Valley the highest stratigraphic rocks found by Markewicz and Dalton include units from Leithsville through the middle part of the Upper Allentown. Stop 1 is considered to be in the lower half of the Limeport Member.
The southeastern edge of the valley is underlain by a normal section of "Kittatinny" sediments lying above the Precambrian.
Along the southwestern border of the valley there are complex structural relationships just before the point where Route 80 enters the Jenny Jump Mountain Precambrian units. There have been various interpretations for this contact between the Precambrian and Paleozoic. These include nappe theories, normal contacts, and various fault interpretations such as an unrooted thrust block.
The Leithsville and Lower Allentown (Limeport) typically form a topographic lowland on the eastern border of the valleys in northern New Jersey. Leithsville rocks generally underlie the lowlands or river valleys and have a greater thickness of unconsolidated sediments -sand, gravel, clay, etc. overlying bedrock than any of the other formations of the "Kittatinny group." The Limeport, typically more resistant than the Leithsville forms a slightly higher pronounced bench. It is generally overlain by overburden that is thinner than the underlying Leithsville overburden, but thicker than overburden Upper Allentown.
Geologic Features
(a) algal units
(b) oolitic and local pisolitic units
(c) churned, lumpy, patchy bioturbidite facies
(d) intraformational conglomerate facies
(e) sandy facies
(f) ruditic, patchy textured clast conglomerate
(g) various dolomite facies, from dolomitic mudstones to medium coarse crystalline dolomite grainstone.
Many varied shallow water carbonate environments can be found at this stop. This is the type of outcrop that a geology professor likes to take his students to so that they can observe the many features that they hear about in the classroom.

Diabase dike within metasedimentary calc-silicates and various gneisses.

STOP 2. Harmonyvale Member of the Ontelaunee Formation
Geologic Setting
This is the first exposure of dolomite on the west side of Jenny Jump Mountain.
During the construction of Rt. 80 the Jacksonburg Limestone was exposed at the east end of the exposure. On the west side of Jenny Jump, the first rock exposed is always the Jacksonburg along with the uppermost part of the Kittatinny sequence.
At Stop 2 exposures of the uppermost-lower Ordovician dolomite present in New Jersey can be observed; this is the Harmonyvale member of the Ontelaunee Formation.
Geologic, Features
(a) dark to black wispy lines or streaks
(b) medium crystalline fetid beds
(c) massive paleo-solution breccia with silt (paleokarst feature)
(d) possible fossils
(e) recent karst features
Black wispy lines are an important feature to be noted here. These seem to have been formed through some deformation process shortly after deposition of the dolomite since the Jacksonburg conglomerates in this region contain dolomite cobbles which have the wispy lines.

Exposures of the upper part of the Allentown Formation

STOP 3. The Rickenbach and Epler Formations
This series of exposures which starts in the upper Allentown Formation and extends up to the Lafayette Member of the Epler forms one of the most complete sections in this area. Off the road, the section continues up into the Jacksonburg Limestone. We will be limiting discussion to the Rickenbach and Epler Formations at this stop.
A. The Rickenbach Formation at this locality measures approximately 290 feet and both the lower and the Hope Members are present. This stop is also the type section for the Hope Member. The features to note are:
a) compare lithologies of the lower member with the Hope Member. .
b) clots of black botryoidal hydrocarbon? material -anthrazalite?
c) sand in the dark aphanitic beds
d) the "7 cherts" horizon
e) the upper chert horizon
f) algal structures
g) Trace amounts of sphalerite occur over a stratigraphic thickness of 225 feet.
B. The Epler at this stop has complete sections of the Branchville and Big Springs Members and a partial section of Lafayette Member. The features to note in the Epler are:
a) compare the alternating medium to massive bedded sequence of the Hope Member of the Rickenbach with very massive bedded laminated dolomites of the Branchville Member of the Epler.
b) the similarity Member of the Branchville with the Lafayette
c) note the siliceous ribbing (interbeds) as well as distinctive reddish weathering characteristic of dolomite.
d) the paleo-solution breccia in the Lafayette Member
e) fossils found in the Big Springs Member.

STOP 4. Rickenbach Formation
From Stop 3 the highway cuts across the Jacksonburg and the Martinsburg Formations west of Route 521. As the highway ascends the large hill known as Mt. Herman a west dipping thrust fault is crossed. The first dolomite exposure is the Limeport Member of the Allentown Formation.
The west side of Mt. Herman is also bounded by a fault. This fault, based upon preliminary mapping is high angle.
Geologic Features
a) the changes in dip
b) the large amount of sulphides present in the rock

4: GEOLOGY OF THE RIDGE AND VALLEY PROVINCE, NORTHWESTERN NEW JERSEY AND EASTERN PENNSYLVANIA
JACK B. EPSTEIN
U. S. Geological Survey
Reston, Va. 22092
The rocks seen in this segment of the field trip range in age from Middle Ordovician to Middle Devonian and constitute a deep basin-continental-shallow shelf succession. Within this succession, three lithotectonic units, or sequences of rock that were deformed semi-independently of each other, have somewhat different structural characteristics. Both the Alleghenian and Taconic orogenies have left their imprint on the rocks. Wind and water gaps are structurally controlled, thus placing doubt upon the hypothesis of regional super-position. Wisconsinan deposits and erosion effects are common. We will examine these geologic features as well as some of the economic deposits in the area.
Figure 1 is an index map of the field-trip area, showing the trip route and quadrangle coverage. Figure 2 is a generalized geologic map,

4: GEOLOGY OF THE RIDGE AND VALLEY PROVINCE, NORTHWESTERN NEW JERSEY AND EASTERN PENNSYLVANIA

Allentown Dolomite in the Hope klippe
Gently dipping Allentown Dolomite in the Hope klippe (see Drake and Lyttle, this volume).

Dolomite and cherty dolomite in the Allentown (?) Dolomite.

Small anticline in the Allentown (?) Dolomite.

Graywacke and slate in the Ramseyburg Member, Martinsburg Fm
Graywacke and slate in the Ramseyburg Member of the Martinsburg Formation. We have just crossed a major fault separating the Middle and Upper Ordovician Martinsburg from Cambrian carbonate rocks in the Hope klippe. <br

Kittatinny Mountain to the right
Kittatinny Mountain to the right (north) held up by quartzites in the Silurian Shawangunk Formation. The mountain is offset to the northeast by a syncline-anticline couplet near the site of the Yards Creek Pumped Storage Project north of Blairstown, N.J.

STOP 1. Discussion Of Trip And Lunch.
See Fig. 4 for stop description. After leaving Stop 1, we will travel down the Paulins Kill Valley, across the Delaware River, travel to the southwest to Pen Argyl, Pa., and stop at a slate quarry in the upper (Pen Argyl) member of the Martinsburg Formation. After crossing Blue Mountain at Wind Gap, we will visit a quarry at Bossardsville. Pa., in Silurian rocks. We will than attempt to drive to the top of Kittatinny Mountain to a vantage point overlooking Delaware Water Gap and examine the Shawangunk Formation and Bloomsburg Red Beds. After passing through the gap we will return to Newark, N.J.

Laminated slates of the Bushkill Member, Martinsburg Fm
Laminated slates of the Bushkill Member of the Martinsburg Formation. Note the typical fine bedding in this member. You will not see similar laminations in slate of its Pen Argyl Member. This is one of the characteristics distinguishing the two predominantly slate-bearing members of the tripartite Martinsburg Formation.

Paulins Kill to right.

Southeast-dipping dolomite of the Epler Formation.
We have crossed the Portland fault which separates the Epler from the Bushkill Member of the Martinsburg Formation.

Crossing Delaware River.
View of Delaware Water Gap to right (north). Tuscarora Power Plant smokestacks to left.

Toll Booth.
Continue straight ahead on U.S. 611S. We will be driving on the Richenbach Dolomite of the Beekmantown Group for about O.5 mile (0.8 km) and then on Wisconsinan kame deposits and till.

View of Kittatinny Mountain to right.

Wisconsinan sand and gravel and some till
The lowlands to the right are mostly underlain by Wisconsinan sand and gravel and some till.

Five Points. Thick glacial deposits
Glacial deposits are as much as 178 feet (54 m) thick in this area.

Graywacke and slates of the Ramseyburg Member, Martinsburg Fm
Crest of hill underlain by graywacke and slates of the Ramseyburg Member of the Martinsburg Formation. Note slate dumps ahead.

Slate dumps of the abandoned Capitol Slate quarry on right.
Slate dumps of the abandoned Capitol Slate quarry on right. Note the much thicker beds than in the Bushkill Member of the Martinsburg seen at mileage 7.4. We are in a slate "run" in the upper part of its Ramseyburg Member. Graywackes are found higher in the sequence and the contact with its overlying Pen Argyl Member is placed where graywacke beds become less dominant.

Flooded New Bangor and Columbia Bangor quarries on left
Flooded New Bangor and Columbia Bangor quarries on left, with nearly recumbent folds.

The Bangor Excelsior quarry on the left has been filled in
The Bangor Excelsior quarry on the left has been filled in, partly with fly ash. It was at least 140 (43 m) feet deep.

Pennsylvania Historical and Museum Commission sign
Pennsylvania Historical and Museum Commission sign on right: "Slate Industry - Robert M. Jones of Wales, who U.S. came here in 1848 as an immigrant, began the slate quarrying industry. The region became a major world center for slate. From here came slate roofs and old-time school slates and pencils."
To the right of the sign are the remains of an old kiln that used to fire the slate for lightweight aggregate (see Epstein, 1974a, for a discussion of the slate industry and potential uses for waste slate).

The Old Bangor slate quarry is over the dumps to the left.
The nearly flat Old Bangor syncline is exposed in the quarry and can be traced for several miles in the area. The quarry also lends its name to the "Old Bangor run", a series of beds that include important commercial slate beds.

Crest of Wisconsinan terminal moraine.
Poor exposures of till may be seen in cuts to the right.

Wisconsinan till to east and Illinoian(?) till to west.
Contact between the Wisconsinan till to east and Illinoian(?) till to west. Note slate dumps from quarry in the Pen Argyl Member of the Martinsburg Formation straight ahead.

STOP 2. Stephans Jackson Slate Quarry
Stephans Jackson Slate Quarry; Structure And Stratigraphy Of The Martinsburg Formation; Slaty Cleavage; Quarrying Operation.
DANGER-STEEP QUARRY WALLS, DO NOT BE TOO BOLD!
The Stephans Jackson Slate Quarry is one of only a few that remain active in the slate belt of Pennsylvania which extends for about 45 miles (72 km) west of the Delaware River. The belt is dotted with more than 400 abandoned slate quarries and prospects. The quarry is currently about 350 feet (110 m) deep. Quarrying and milling methods have changed little for the last 50 years, and are still much the same as described by Behre (1933). The slate is used for roofing, blackboards, flagging, aquaria bottoms, sills and treads, and billiard table tops. Immediately southwest over the dumps is the abandoned Parsons quarry. which reportedly was more than 900 feet (274 m) deep, the deepest slate quarry in the United States.
The Stephans Jackson Slate Quarry is in an overturned syncline whose axial plane dips gently to the southeast (fig. 5). A bedding-slip fault forms much of the northwest wall of the quarry. Slaty cleavage and bedding in the overriding block are dragged into the fault and a slip cleavage that shows antithetic movement to the fault, has developed in the drag fold (see inset, fig. 5). In general, slaty cleavage forms a gentle arch and fans the fold by about 14°. The fault is marked by a gouge or "spar zone" that is as much as 2 feet thick and filled with quartz and calcite.
The fault zone is a marked zone of weakness in the rock. In 1948, the northeast section of the quarry was being worked when a large mass of rock slipped down into the quarry along the zone, killing two workers below. That part of the quarry was abandoned, and the presently active section was started. Note the pins that were bent by the sliding mass in the northern corner.
The sequence of deformation was complex. Bedding-plane slickensides that are offset by cleavage indicate that initial flexural-slip folding was followed by passive folding (fig. 46, Epstein and Epstein, 1969). As the folds continued to tighten, failure was again along bedding, producing the bedding-slip fault, warping of slaty cleavage, and formation of crenulation cleavage parallel to the axial plane of the cleavage fold. Movement along the bedding-slip fault was up to the northwest, as indicated by the drag, but steps on one of two slickensided surfaces in the fault zone indicate an opposite sense of movement, perhaps due to earlier flexural slip.
The origin of slaty cleavage in the Martinsburg Formation, as well as in rocks above and below, has been a focus of considerable attention during the last two decades. Did it form by tectonic dewatering or did it form under conditions of low-grade metamorphism? Mapped relationships and petrologic considerations led me to conclude that it formed as a product of metamorphism (Epstein, 1974b) by a combination of the following processes: mechanical rotation of detrital grains parallel to the cleavage, corrosion of quartz by pressure solution and migration of silica. intrusion and flow of pelitic material, grain diminution by granulation, and by recrystallization and neocrystallization.
The Stephans Jackson Slate Quarry is in the Pen Argyl Member (upper) of the Martinsburg Formation and is about 1500 feet (457 m) above the contact with its Ramseyburg Member (middle) (fig. 6). The Pen Argyl is typically thick bedded, containing some beds of gray slate more than 10 feet (3 m) thick. The member is cyclically bedded, each cycle consisting of medium-gray slate grading up into grayish-black carbonaceous slate. Graywacke may form the base of some of the cycles.
For more than 70 years there has been controversy regarding the number of members in the Martinsburg (see Drake and Epstein, 1967). On the basis of the very characteristic difference in bedding thickness between the lower (Bushkill) and upper (Pen Argyl) members, and as proved by detailed mapping (fig. 6), I have mapped three members in this area, nearly in the same manner as Behre (1933). The Pen Argyl cannot be the Bushkill repeated by folding as earlier suggested by Stose (1930), for example. Recently, Stephens and others (1979) argued for a two-fold division based on fossil collections in the Schoharie "Ridge' area, about 35 miles (56 km) to the southwest. This bipartite interpretation, however, is presently clouded by structural complications that may be present in that area (Epstein and others, 1972; Lyttle, 1979).

Gentle slopes underlain by colluvium and Illinoian(?) till
We will be riding on gentle slopes underlain by colluvium and Illinoian(?) till which cover the Pen Argyl Member of the Martinsburg. Quartzites in the Shawangunk Formation are seen in cliffs in Blue Mountain to the right.

The low col straight ahead is Wind Gap
Exposures of the lower (Minsi) member of the Shawangunk Formation in woods on left. The low col straight ahead is Wind Gap, underlain by nearly vertical quartzites and veneered with weathered colluvium.

Red shale, siltstone, and sandstone of the Bloomsburg Red Beds.
For about 1.5 miles (2.4 km) along Pa. 33, the Bloomsburg is thrown into many small folds that are superimposed on the Ross Common Creek syncline and Wind Gap anticline. Note the well-developed cleavage in the Bloomsburg.

Chestnut Ridge to the left
Chestnut Ridge to the left, underlain by complexly folded rocks of Late Silurian and Early Devonian age.

Bloomsburg Red Beds to right.
Cherry Ridge straight ahead held up by sandstones in the Ridgeley and Palmerton Sandstones.

Wisconsinan till in road cut to right.

Cut through Cherry Ridge
Cut through Cherry Ridge in South-dipping overturned Esopus and Schoharie Formations and Palmerton Sandstones.

Many abandoned clay pits
Many abandoned clay pits in deeply weathered Buttermilk Falls Limestone are in woods to right. These are in saprolites as much as 250 feet (76 m) deep. The clay is used as whitener in cement.

Panoramic view to left (see fig. 7).

Hill to right underlain by Decker Formation and Bossardville Limestone.

STOP 3. Hamilton Stone Company Quarry.
Stratigraphy And Structure Of Upper Silurian Rocks In Cherry Ridge.
Three Upper Silurian units are well exposed in the quarry in a series of upright to tight and slightly overturned folds (fig. 8). The units are, from top to bottom:
Wallpack Center Member of the Decker Formation:
Medium-bedded and lenticular medium.gray to medium-light-gray, fine-to coarse-grained, quartzose limestone, medium-gray, fine-to coarse-grained calcareous sandstone, siltstone, and conglomeratic sandstone, containing brachiopods, rugose and colonial corals, bryozoans, and crinoid columnals. Leperditiid ostracodes are abundant near basal mud-cracked dolomite. Upper contact concealed. About 70 feet (21 m) exposed. Forms cap rock. Useful for crushed stone.
Bossardville Limestone:
Graded laminated to very thin-bedded, dark-gray, fine-to very fine grained pyritic argillaceous mud-cracked limestone with scour-and-fill at base of graded units and leperditiid ostracodes. Uppermost beds very finely laminated limestone and smaller amounts of dolomite. About 95 feet (29 m) thick. Quarry rock useful for crushed stone.
Poxono Island Formation:
Interbedded and interlaminated medium-gray, calcareous dolomite, medium-gray and mottled pinkish-gray-green to medium-greenish-gray to gray, very fine grained dolomite, grayish-red limestone, and light-grayish-yellow-green shale and calcareous shale; contains several mud-crack intervals. Uppermost dolomite contains color contortions. About 40 feet (12 m) exposed.
These rocks are interpreted to have been deposited in a complex and generally transgressive tidal-flat barrier-bar shallow subtidal environment on the basis of lithology, sedimentary structures, texture, bedding characteristics, fossils, and lateral facies (see Epstein and others, 1967, and Epstein and Epstein, 1969, p. 192-196).
The structure in the quarry area is dominated by about 25 folds whose axial planes strike N. 50° - 60° E. and whose axes plunge about 5°SW. These folds are disharmonic on the Kemmererville anticline in the Bloomsburg Red Beds in the underlying lithotectonic unit. The Poxono Island Formation is believed to be separated from the Bloomsburg by a decollement (see cross section, fig. 8). The anticlinal ridge underlain by the Bloomsburg rises as we travel to the northeast after leaving the quarry.
Folding was initiated by flexural slip followed by passive folding and development of cleavage. This is indicated by cleavage that wrinkles bedding-plane slickensides. In a few places, such as in the 10 foot-(3 m) wide fault zone in the east corner of the quarry, a slip cleavage cuts the earlier cleavage.
The stratigraphic units behaved differently during deformation. The more pelitic rocks failed passively, with development of prominent cleavage, whereas the more competent carbonate rocks and sandstones in the Decker and the Bossardville were concentrically folded and in places formed fold mullions. This small-scale folding is somewhat disharmonic and folds in the Poxono Island are generally tighter than in overlying rocks. This disharmonic folding is similar to the structure on a regional scale.
Places that we may visit in the quarry depend on the whims of the shovel, but we will probably go to three localities shown in figure 8: (A) A very tight anticline in the Poxono Island Formation and a fault that cuts out about 50 feet (15 m) of the Bossardville Limestone are conspicuous in outcrop here (fig. 9). As we look to the west from a high point we can see the Trimmers Rock and Catskill Formations in the southwest-plunging Weir Mountain syncline. To the north, the Pocono Plateau, Godfrey Ridge, and glacial lake deposits are seen. A well-developed ice-contact delta and esker marks a recessional position of the Wisconsinan glacier and the northeastern ice-defended boundary of glacial Lake Sciota. (B) Fold mullions and many sedimentary features are present in the Decker Formation in this overturned syncline. (C) Well-developed mudcracks, edgewise conglomerate, and other structures suggestive of supratidal deposition are of interest in the Poxono Island Formation. Cleavage that warps bedding slickensides is common in the Bossardville.

Abandoned quarries in the Bossardville Limestone to right and left.

View to right of Cherry Valley; Godfrey Ridge on left;
View to right of Cherry Valley; Godfrey Ridge on left; rounded ridge in the middleground is underlain by the Bloomsburg Red Beds in the southwest-plunging Kemmererville anticline; northwest-dipping quartzites in the Shawangunk Formation hold up Kittatinny Mountain on the skyline.

Poxono Island Formation exposed in creek to right.

Near-vertical Bossardville Limestone on left.

Flat floor underlain by glacial lake clays, etc.
Flat floor of Cherry Valley on right partly underlain by glacial lake clays, silts, and sands. Kittatinny Mountain forms skyline to right.

Stormville Member of the Coeymans Fm
Village of Stormville, type locality of the Stormville Member of the Coeymans Formation.

Whiteport Dolomite Member of the Rondout Fm
Very well developed columnar mud cracks in the Whiteport Dolomite Member of the Rondout Formation on left.

Kame ahead.
Low hill ahead is a kame containing Wisconsinan sand and gravel.

Coeymans Formation on left in slump block.

Ridgeley Sandstone in float on left.
Ridgeley Sandstone, which caps Godfrey Ridge, in float on left.

The Bloomsburg Red Beds in Kemmererville anticline to right rises up-plunge.

Stormville Member of the Coeymans Fm
Good exposures of the Stormville Member of the Coeymans Formation in steep slope beyond farm house on right.

Cross Cherry Creek.

Entering Wildcat Hollow.
Exposures of northwest-dipping red and green clastic rocks of the Bloomsburg Red Beds in the northwest limb of the Kemmererville anticline.

Crest of Kemmererville anticline.
South of here the rocks dip gently southeast.

Crest of Kemmererville anticline.

Southeast limb of Kemmererville anticline.
Turn right and descend southeast limb of Kemmererville anticline.

Trough of Poplar Valley Syncline.
Note ten foot long (3 m) long glacial erratics of Buttermilk Falls Limestone in creek to right.

Contact Shawangunk Fm / Bloomsburg Red Beds
Contact between the Shawangunk Formation and Bloomsburg Red Beds. Ascend (we hope) steep dirt road to crest of Kittatinny Mountain.

Crest of Kittatinny Mountain.
Proceed east (to left) along dirt road to Stop 4. The quartzites of the Shawangunk Formation here are overturned to the southeast, dipping about 50°. As we proceed eastward, the rocks become vertical and then dip moderately northwest at Delaware Water Gap.

Microwave Tower of AT&T on right.

Good view to left.
Good view of Kemmererville anticline, Godfrey Ridge, and the Pocono Mountains to the north (left).

STOP 4. Delaware Water Gap Overlook.
Stratigraphy And Structure Of The Shawangunk Formation: Origin Of Wind And Water Gaps; Nature Of The Ordovician-Silurian Contact; Summary Of Trip.
Park at end of road. Disembark and follow Appalachian Trail to edge of Delaware Water Gap.
The three members of the Shawangunk Formation, basically two conglomeratic quartzite units separated by a sequence of argillites and quartzites, and the lower part of the Bloomsburg Red Beds, are well exposed in the gap. The Minsi and Tammany Members of the Shawangunk are interpreted to have been deposited by braided streams flowing off highlands uplifted during the Taconic orogeny, whereas the Lizard Creek Member of the Shawangunk represents a complex transitional continental-marine environment (Epstein and Epstein, 1967. 1969, 1972).
Fining-upward sequences in the Bloomsburg are indicative of meandering streams. The contact between the Shawangunk and the Bloomsburg, based on an upward change from gray to red rocks, is extremely irregular, particularly near the village of Delaware Water Gap, 1.5 miles (2.4 km) to the northwest (see fig. 10 and Epstein 1973).
The Shawangunk in the gap dips moderately to the northwest (figs. 10 and 11) and contains many small satellitic folds. The beds reverse their dip in the Dunnfield Creek syncline, and do so again in the Cherry Valley anticline. We will see the northwest limb of the Cherry Valley anticline at the toll booth on Interstate 80 in the village of Delaware Water Gap. Many small undulations, wedges, and bedding slips in the Bloomsburg are superimposed on the larger Dunnfield Creek syncline. Movement of these structures suggests sliding to the northwest.
The regional strike between the Martinsburg and the Shawangunk in this area differs by about 15°, and the Ramseyburg-Pen Argyl contact in the Martinsburg is buried beneath the Shawangunk 1.2 miles (2 km) southwest of the gap. The difference in structural trends is very apparent in the field, on aerial photographs, and high-altitude imagery. This regional Taconic unconformity is well documented. On the basis of several lines of reasoning, however, I believe the cleavage in the Martinsburg at the gap to be Alleghenian in age. Note that the cleavage in the Martinsburg arches, whereas bedding maintains its general northwest dip (fig. 10). indicating that the arching was not caused by external rotation during post-Taconic deformation. Rather, I believe that the arching is due to a pressure-shallow mechanism whereby cleavage in pelitic rocks adjacent to more competent rocks fans away from the axis of a syncline (see Epstein and Epstein, 1969, p. 166-167). The upper limb of the syncline in the Shawangunk is eroded away, of course, but it can be seen down-plunge to the southwest where the beds are overturned, such as at Totts Gap.
Glacial striae and roches moutonnees are common on top of Kittatinny Mountain. They trend about due south, but the Wisconsinan glacier was deflected more to the southwest on the slopes and in the valleys, following the trend of the topography.
For many years there have been numerous discussions on the origin of wind and water gaps and how that origin relates to Appalachian geomorphic development. Basically, two contrasting viewpoints have been presented. One favors coincidental location of the gaps due to superposition from a coastal-plain cover (e.g., Johnson, 1931). The other argues for northwestward headward erosion from the original drainage divide to the southeast along lines or points of structural weakness. The test of superposition, according to Strahler (1945), was to show lack of structural control for the location of the gaps.
For 40 miles (64 km) along Kittatinny and Blue Mountains and the ridges to the north, I have mapped the geology at 12 major gaps in Pennsylvania and New Jersey. The gaps are located where one or more of the following geologic conditions exist: (1) folds die out within short distances, (2) beds dip steeply and resistant units have narrow outcrop widths, and (3) there is more intense local folding or shearing than nearby (see Epstein, 1966).
At Delaware Water Gap the crest of Kittatinny Mountain in Pennsylvania is offset 800 feet (245 m) to the southeast from the trend of the crest in New Jersey. However, a transverse fault is not present through the gap (as has been suggested by several workers), because the contacts of the three members within the Shawangunk are not displaced at river level (fig. 10). The offset of the ridge crest is due to downward flexing of the rocks on the Pennsylvania side whereas the rocks maintain a constant dip on the New Jersey side (fig. 12). The flexure can be seen by looking west from the New Jersey bank. The abrupt change in strike at the gap site must have resulted in extensive fracturing in the brittle Shawangunk. Structural control is therefore thought to have determined the location of the gap. Also, the Bloomsburg Red Beds just north of the gap are involved in about 15 folds that die out rapidly to the southwest, including the large Dunnfield Creek syncline and Cherry Valley anticline. This structural situation is present at other large gaps, such as Wind Gap and Lehigh Gap. The rocks were probably more highly sheared here, and resistance to erosion was less than in the areas between gaps where similar folds were not observed.
Thus, data supporting structural control for location of the gaps does not favor the concept of regional superposition. Rather, it favors those hypotheses that maintain that gaps are located in zones of structural weakness where erosion was most effective during the course of stream competition, along the ancestral drainage divide.
Time permitting, we will summarize the themes of this trip: structural comparisons of the several lithotectonic units, ages of deformation, regional stratigraphic framework, history of sedimentation, and Quaternary history.

Crest of Kemmererville anticline.
Crest of Kemmererville anticline. Descend northwest limb of anticline. A thin layer of till caps bedrock in most of this area.

Stratified Wisconsinan sand and gravel in kames
Stratified Wisconsinan sand and gravel in kames underlying golf course on left right. Godfrey Ridge, underlain by complexly folded Upper Silurian and Lower Devonian rocks, forms the ridge beyond Cherry Valley.

NW dipping rocks in the Shawangunk Formation
Exposures are northwest-dipping rocks in the Shawangunk Formation on the northwest limb of the Cherry Valley anticline.

Shawangunk Formation on right dips to south
Exposures of Shawangunk Formation on right dip to south on the southeast limb of the Cherry Valley anticline.

Undulations in the Bloomsburg Red Beds
Undulations in the Bloomsburg Red Beds on left are superimposed on the northwest limb of the Dunnfield Creek syncline. Many wedges and bedding-plane slips are exposed in these rocks. Note the well-developed cleavage.

Water-worn and glacially striated Bloomsburg on left.

Kame terrace on left.

Shawangunk Fm / Bloomsburg Red Beds contact
Contact between Shawangunk Formation and Bloomsburg Red Beds covered on left.

Massive conglomeratic quartzites on left.
Massive conglomeratic quartzites of the upper (Tammany) member of the Shawangunk Formation on left.

(Lizard Creek) member of the Shawangunk Fm
Interbedded quartzite. siltstone, and shale in the middle (Lizard Creek) member of the Shawangunk Formation on left.

(Mimi) member of the Shawangunk Fm
Quartzites of the lower (Mimi) member of the Shawangunk Formation on left. Note to the right that the Shawangunk dips about 45° at river level and is warped to lesser dips halfway up the mountain (fig. 12). Note gabions retaining the colluvium on left. The contact of the Martinsburg and Shawangunk is buried here but was discussed by Beerbower (1956).

4A: ALTERNATE STOP 4
In case we do not go to Stop 4, follow this road log to alternate Stop 4, picking up at mileage 36.9.

4A: ALTERNATE STOP 4

Steeply dipping beds, and well developed cleavage.
Steeply dipping Port Ewen Shale of the Helderburg Group, Shriver Chert and Ridgeley Sandstone of the Oriskany Group, and Esopus Formation on left. Note well-developed cleavage in the Esopus.

Crest of Godfrey Ridge
Crest of Godfrey Ridge supported by siliceous siltstones in the Esopus Formation. The road descends through several folds in the Esopus and Schoharie Formations and Buttermilk Falls Limestone.

Slightly overturned Buttermilk Falls Limestone on right.

Overturned Schoharie Formation on right.
The road ascends through several folds.

Crest of Godfrey Ridge seen on left
Crest of Godfrey Ridge, underlain by the Esopus Formation seen on left with well-developed cleavage. View to right of Cherry Valley, the Kemmererville anticline underlain by the Bloomsburg Red Beds in the middleground, and Kittatinny Mountain, underlain by Shawangunk quartzites, in the skyline.

Esopus Formation on left.

Ridgeley Sandstone on left underlain by Shriver Chert.

Port Ewen Shale on left.
The road descends through various Wisconsinan deposits.

Northwest·dipping gray sandstone Shawangunk Formation on right.

Crest of Cherry Valley anticline.
Note the lateral gradation of red, green, and gray beds at this contact between the Shawangunk Formation and Bloomsburg Red Beds.

Resort Point Overlook on left.
Note the undulations in the Bloomsburg across the river which are superimposed on the northwest limb of the Dunnfield Creek syncline. Cleavage is well developed and wedges and bedding slips are common.

Note "Indian Head" in cliffs
Note "Indian Head" in cliffs of the Shawangunk on the left side of the gap.

Shawangunk-Bloomsburg contact on right.

ALTERNATE STOP 4.
Stratigraphy And Structure Of The Shawangunk Formation: Origin Of Wind And Water Gaps; Nature Of The Ordovician-Silurian Contact; Summary Of Trip.
Copied from description for STOP4:
The three members of the Shawangunk Formation, basically two conglomeratic quartzite units separated by a sequence of argillites and quartzites, and the lower part of the Bloomsburg Red Beds, are well exposed in the gap. The Minsi and Tammany Members of the Shawangunk are interpreted to have been deposited by braided streams flowing off highlands uplifted during the Taconic orogeny, whereas the Lizard Creek Member of the Shawangunk represents a complex transitional continental-marine environment (Epstein and Epstein, 1967. 1969, 1972).
Fining-upward sequences in the Bloomsburg are indicative of meandering streams. The contact between the Shawangunk and the Bloomsburg, based on an upward change from gray to red rocks, is extremely irregular, particularly near the village of Delaware Water Gap, 1.5 miles (2.4 km) to the northwest (see fig. 10 and Epstein 1973).
The Shawangunk in the gap dips moderately to the northwest (figs. 10 and 11) and contains many small satellitic folds. The beds reverse their dip in the Dunnfield Creek syncline, and do so again in the Cherry Valley anticline. We will see the northwest limb of the Cherry Valley anticline at the toll booth on Interstate 80 in the village of Delaware Water Gap. Many small undulations, wedges, and bedding slips in the Bloomsburg are superimposed on the larger Dunnfield Creek syncline. Movement of these structures suggests sliding to the northwest.
The regional strike between the Martinsburg and the Shawangunk in this area differs by about 15°, and the Ramseyburg-Pen Argyl contact in the Martinsburg is buried beneath the Shawangunk 1.2 miles (2 km) southwest of the gap. The difference in structural trends is very apparent in the field, on aerial photographs, and high-altitude imagery. This regional Taconic unconformity is well documented. On the basis of several lines of reasoning, however, I believe the cleavage in the Martinsburg at the gap to be Alleghenian in age. Note that the cleavage in the Martinsburg arches, whereas bedding maintains its general northwest dip (fig. 10). indicating that the arching was not caused by external rotation during post-Taconic deformation. Rather, I believe that the arching is due to a pressure-shallow mechanism whereby cleavage in pelitic rocks adjacent to more competent rocks fans away from the axis of a syncline (see Epstein and Epstein, 1969, p. 166-167). The upper limb of the syncline in the Shawangunk is eroded away, of course, but it can be seen down-plunge to the southwest where the beds are overturned, such as at Totts Gap.
Glacial striae and roches moutonnees are common on top of Kittatinny Mountain. They trend about due south, but the Wisconsinan glacier was deflected more to the southwest on the slopes and in the valleys, following the trend of the topography.
For many years there have been numerous discussions on the origin of wind and water gaps and how that origin relates to Appalachian geomorphic development. Basically, two contrasting viewpoints have been presented. One favors coincidental location of the gaps due to superposition from a coastal-plain cover (e.g., Johnson, 1931). The other argues for northwestward headward erosion from the original drainage divide to the southeast along lines or points of structural weakness. The test of superposition, according to Strahler (1945), was to show lack of structural control for the location of the gaps.
For 40 miles (64 km) along Kittatinny and Blue Mountains and the ridges to the north, I have mapped the geology at 12 major gaps in Pennsylvania and New Jersey. The gaps are located where one or more of the following geologic conditions exist: (1) folds die out within short distances, (2) beds dip steeply and resistant units have narrow outcrop widths, and (3) there is more intense local folding or shearing than nearby (see Epstein, 1966).
At Delaware Water Gap the crest of Kittatinny Mountain in Pennsylvania is offset 800 feet (245 m) to the southeast from the trend of the crest in New Jersey. However, a transverse fault is not present through the gap (as has been suggested by several workers), because the contacts of the three members within the Shawangunk are not displaced at river level (fig. 10). The offset of the ridge crest is due to downward flexing of the rocks on the Pennsylvania side whereas the rocks maintain a constant dip on the New Jersey side (fig. 12). The flexure can be seen by looking west from the New Jersey bank. The abrupt change in strike at the gap site must have resulted in extensive fracturing in the brittle Shawangunk. Structural control is therefore thought to have determined the location of the gap. Also, the Bloomsburg Red Beds just north of the gap are involved in about 15 folds that die out rapidly to the southwest, including the large Dunnfield Creek syncline and Cherry Valley anticline. This structural situation is present at other large gaps, such as Wind Gap and Lehigh Gap. The rocks were probably more highly sheared here, and resistance to erosion was less than in the areas between gaps where similar folds were not observed.
Thus, data supporting structural control for location of the gaps does not favor the concept of regional superposition. Rather, it favors those hypotheses that maintain that gaps are located in zones of structural weakness where erosion was most effective during the course of stream competition, along the ancestral drainage divide.
Time permitting, we will summarize the themes of this trip: structural comparisons of the several lithotectonic units, ages of deformation, regional stratigraphic framework, history of sedimentation, and Quaternary history.

Cold Air Cave on right.
Cave is formed by a large slab of quartzite float resting on smaller stones. Cold air stored in the colluvium flows down through the rocks and into the cave. It was used for storage of soft drinks more than 50 years ago (Stone, 1932).

Ramseyburg member of the Martinsburg Fm
Outcrop of the middle (Ramseyburg) member of the Martinsburg Formation on right. Beds dip 32° NW and cleavage dips 7° NW.

Very coarse kame-terrace deposits on right.
These deposits flank both sides of Delaware Valley for more than 1 mile downstream.

Quarries in Bushkill member of the Martinsburg Fm
Two quarries hidden in narrow valleys on right are in the lower (Bushkill) member of the Martinsburg Formation.

5: ALLEGHANIAN THRUST FAULTS IN THE KITTATINNY VALLEY, NEW JERSEY
Avery Ala Drake, Jr., and Peter T. Lyttle
U. S. Geological Survey
Reston, Virginia
Introduction
Major thrust faults involving both Proterozoic basement and Cambrian and Ordovician sedimentary rocks have been known in the Kittatinny Valley at least since the geologic mapping that resulted in the New Jersey State Geologic Map (Lewis and Kummel, 1910-12) and the Raritan Folio (Bayley and others, 1914). Three important thrust faults, the Jenny Jump, Portland, and Federal Springs, display quite different tectonic styles at the present level of erosion and, thereby, serve as showpieces of thrust fault tectonics for this part of the central Appalachian orogen. The purpose of this field trip is to demonstrate these three thrust faults and to present evidence for their late, probably Alleghanian age. In addition, attendant structural features such as autoclastic melange and chert mylonite will be shown.
Road log
The field trip begins in the parking lot at Rutgers-Newark and reaches the Kittatinny valley by the garden state parkway and interstate 280 and 80. Subsequent to stop 9, the trip returns to Rutgers-Newark by route 206, interstates 80 and 280, and the Garden State Parkway. Geologic notes are provided for the route 206 segment of the return. Field trip stops 1-8 are in the Blairstown 7.5-minute quadrangle and stop 9 is in the Newton East quadrangle. (A copy of these two quadrangles will be provided to each participant.) The trip route also traverses the Tranquility, Newton East, and Stanhope quadrangles.

5: ALLEGHANIAN THRUST FAULTS IN THE KITTATINNY VALLEY, NEW JERSEY

Exposures of sandstone and mudstone
Alternating beds of red sandstone and mudstone with a few thin interbeds of gray siltstone and dark gray to black micaceous shale, occurring below the first overpass. These siltstones yield a probable late Norian palynoflora and occur about 1100 m below the First Watchung Mountain Basalt (Cornet and Traverse, 1975, p. 27). Sporadic exposures of sandstones and mudstones with fining-upward sequences, characteristic of meandering streams, occur along Interstate 280 for the next 4.4 miles.

Basalt of the First Watchung Mountain
Contact with the underlying red beds is concealed. Note: characteristic radial columnar joint pattern.

Basalt of the Second Watchung Mountain
Contact with the underlying beds is concealed.

Basalt of the Third Watchung Mountain
Basalt of the Third Watchung Mountain is exposed to the south of the highway.

Passaic River Valley
The valley is underlain with glacial clays and silt that were deposited in Glacial Lake Passaic. The lake formed as glacial meltwaters were impounded between the New Jersey Highlands to the west and the Watchung Mountains to the south and east (see Kummel, 1940).

First preCambrian rocks
Water tower on right (left?) is on Proterozoic (Precambrian Y) rocks of the N.J. Highlands.

Begin climb from Jurassic-Triassic Basin into the Highlands.

Steeply dipping amphibolites.
First roadcuts of Highlands rocks, here steeply dipping amphibolites.

Biotite-quartz-plagioclase gneiss.
Outcrops of very rusty metasedimentary biotite-quartz-plagioclase gneiss.

Field area of Paul Sims
This was field area of famous Precambrian geologist Paul Sims. The ridge to right front is held up by the Silurian Green Pond Conglomerate.

Cruddy outcrops of Proterozoic gneiss.

Lots of glacial till on left.

Biotite-quartz-plagioclase gneiss
Large outcrop of strongly layered biotite-quartz-plagioclase gneiss of Proterozoic age on right.

Outcrops of hornblende granite of Proterozoic age.

Outcrops of Proterozoic rocks.

Musconetcong River
Formerly a great trout stream, now a temporary habitat for fish between hatchery and skillet.

Continuous outcrops of Proterozoic rocks
Continuous outcrops of Proterozoic rocks on Allamuchy Mountain. These rocks are in the core of the Allamuchy nappe of the Musconetcong nappe system of the Reading Prong nappe megasystem. The rocks cropping out at the rest stop to the left and above the highway are severely deformed and contain several flat thrust faults.

Scenic overlook.
If weather is fine, bus will pull off here and we will give a short briefing on the regional geology and this field trip. Looking north from this place, one has an excellent view of the Kittatinny Valley and Jenny Jump Mountain.

Bold outcrops of Proterozoic rocks.

Granite gneiss containing mafic segregations
This outcrop of granite gneiss contains mafic segregations of plagioclase, epidote, garnet and magnetite surrounded by a rind of almandine garnet in a more felsic matrix of potassium feldspar, quartz, plagioclase, epidote, and accessories. Foliation appears to parallel gneissic layering and is oriented N. 45° E., 39° SE. Pegmatites are roughly parallel to foliation, but upon close inspection are seen to cut it.

Entering Bear Swamp.
Rocks in this area are Allentown Dolomite of Late Cambrian age.

Nice outcrop of Allentown Dolomite.
Beds strike N. 82° W., and dip 15° NE, cleavage strikes N. S5° W. and dips 22° NE, their intersection, roughly parallel to axes of small folds, plunges 14° N. 18° W. The beds face up and are probably in the upper limb of the Allamuchy nappe.

Begin the ascent of Jenny Jump Mountain
Here we are crossing the trace of the Shades of Death thrust which brings rocks of the Allamuchy nappe onto rocks of the Jenny Jump klippe of the Jenny Jump thrust sheet. The Proterozoic rocks here are dominated by a sequence of marble, amphibolite, and lesser calcsilicate rock.

Lower Paleozoic rocks beneath the thrust fault
We have passed through the Proterozoic rocks of the Jenny Jump klippe and here enter a sequence of lower Paleozoic rocks beneath the thrust fault. Here the outcrops are Epler Formation of the Beekmantown Group of Early Ordovician age. These outcrops contain fairly abundant solution collapse breccia. Many bedding surfaces in these rocks are also thrust faults and a fair amount of carbonate mylonite has been formed. Axes of small folds plunge 5° S 25° E; beneath the Proterozoic rocks of the Jenny Jump klippe.

Nice outcrops of Allentown Dolomite.
Here we are about on the crest of an anticline which plunges 5° N 45° E. Beds face up as shown by good algal stromatolites.

Long continuous outcrop
Long continuous outcrop beginning in Allentown Dolomite, Rickenbach Dolomite, Epler Formation, and Ontelaunee Formation. (See Markewicz and Dalton, this Guidebook.)

Epler / Rickenbach contact
Large outcrop of sandy, mottled, laminated dolomite of the Epler Formation. The contact with the Rickenbach Dolomite is about in middle of this cut. It is placed at the contact of laminated, burrowed, mottled, finely crystalline dolomite (Epler) with thick-bedded, dark-medium-gray, medium crystalline dolomite (Rickenbach). Rock contains abundant cascade-type folds which plunge 5°-10° N 25° E.

Outcrops of Jacksonburg Limestone.
Most of rock here is crystalline limestone but some beds are dark-gray, more argillaceous cement rock. Axes of small folds here plunge 20° N 5° W. Slickensides on bedding surfaces plunge down the dip.

More outcrops of Jacksonburg Limestone.

More outcrops of Jacksonburg Limestone.
More outcrops of Jacksonburg Limestone. A lot of conglomerate here. Outcrops to south of Interstate are Bushkill Member of the Martinsburg Formation. Slaty cleavage, which strikes N 60° E and dips 20° NW., is principal planar element in these rocks. The cleavage surfaces are marked by a strong extension lineation which plunges 5° N 35° W. and crenulations which are nearly horizontal N. 70° E. Strong crenulation cleavage strikes N. 70° E. and dips 75° SE.

Bushkill Member of Martinsburg Fm
We are driving on Bushkill Member of Martinsburg Formation. Outcrops to right are Allentown Dolomite in the large Hope klippe of the Jenny Jump thrust sheet. The dolomite beds face up, dip gently northwest, and contain abundant algal stromatolites and oolite.

Here we are at the base of the Hope klippe.
The outcrop to the right is oolitic, shaley, Allentown Dolomite, probably the lowest beds of that unit. The beds dip gently to the northwest and face up.

Hope, a pre-revolutionary Moravian settlement
Entering the town of Hope which is a pre-revolutionary Moravian settlement.

Outcrop on right is Leithsville Formation
Outcrop on right is Leithsville Formation of Early and Middle Cambrian age. The gently northwest dipping rocks are right at the sole of the Hope klippe. They dip gently northwest, have a vague mylonitic foliation which strikes N. 45° E. and dips 18° NW., and a general mangled appearance.

Outcrops on right are Jacksonburg Limestone.
The rock here is well-bedded, calcarenite grainstone that contains abundant fossil hash and small scattered pebbles of dolomite. The beds strike N. 75° W. and dip 25° NE. They have a cleavage which strikes N. 55°E. and dips 15° SE.; this cleavage is marked by an extension lineation which plunges approximately down the dip. The intersection of the cleavage with the bedding plunges 7° N 88° E. These rocks are autochthonous to the Jenny Jump thrust sheet and belong to an as yet unnamed tectonic element of the Musconetcong nappe system of the Reading Prong nappe megasystem.

Ontelaunee Fm of Beekmantown Group
Outcrop on right is Ontelaunee Formation of Beekmantown Group. This is Field Trip Stop 2 to which we will return.

Poor outcrop of Allentown Dolomite
Poor outcrop of Allentown Dolomite on lawn on the right. Abundant, excellent outcrops of Allentown on wooded knoll to to the east.

STOP 1. Jenny Jump klippe of Jenny Jump thrust sheet
Speaker, Peter Lyttle.
(Field trippers will disembark, bus driver will take bus to top of hill to Hissim Road to turn around. He should wait there for 30 minutes, and return down the hill to pick up the field trip in front of the house at the base of hill.)
We are on the northwest edge of the main mass of the Jenny Jump thrust sheet on the northwest side of Jenny Jump Mountain. The Proterozoic rocks we will be looking at here are primarily hornblende granite gneisses with minor fine-grained mafic dikes. These rocks structurally overlie the lower Paleozoic rocks of the valley that we have just driven through. Although the Jenny Jump thrust is nowhere exposed, there are several locations along the north side of Jenny Jump Mountain where outcrops of Paleozoic carbonate with structures dipping to the southeast occur within a few tens of meters of the Proterozoid gneisses. It is clear in map pattern (see Figure 4) that the Jenny Jump thrust truncates both contacts and structures in Paleozoic rocks.
In order to see all of the structures mentioned below, it is necessary to hike a hundred meters or so along the side of Jenny Jump Mountain in this area of semi-continuous outcrop. Almost all of the structures can be seen in several places and the diligent tripper should be able to find them all on his/her own. The most important structure to note at this outcrop is well-developed foliation that is, in most places, parallel to compositional layering and is axial planar to the rarely observed earliest isoclinal folds that are presumably Grenville in age. This foliation is seen in both the gneiss and mafic dikes. The orientation of the dikes appears to roughly parallel the foliation, but can by at an angle to compositional layering, indicating that the dikes intruded either during or before this early folding episode. This foliation is folded by a later event interpreted to be the emplacement of the Jenny Jump thrust sheet. Over most of Jenny Jump Mountain the foliation strikes roughly N. 60°E. and dips 30-40° to the southeast. However, at several places along the northwest edge of Jenny Jump Mountain. it is common to find the foliation folded by large, open, upright to slightly overturned folds .
There has been considerable slip on many foliation planes (evidenced by slickensides) and if the rocks at this outcrop are not wet or in the shade, the field tripper will note many narrow zones of mylonite that are roughly parallel to the foliation. Locally, these zones of mylonite are brecciated. These outcrops are very near the sole of the Jenny Jump thrust sheet and it is likely that the mylonitization and brecciation are related to the emplacement of the thrust sheet.
In one area of these outcrops, a thin mafic dike is cut by numerous small-scale thrusts spaced 3-10 cm apart. The sense of movement is always toward the NNW.
The gneisses here are quite magnetic, the magnetite probably being produced with chlorite at the expense of hornblende. Very little fresh hornblende is seen in thin section. Quartz, microcline oligoclase, minor hornblende and magnetite, and accessory zircon and apatite make up the bulk of the gneisses. The oligoclase and hornblende are commonly altered, and the quartz is highly strained and occurs in long sheared out stringers.

STOP 2. Bedding-parallel faults in the Ontalaunee Fm
Speaker. Peter Lyttle. (Driver pull bus onto turnout on left side of road.)
This will be a very quick stop to illustrate bedding-parallel shear and mylonitization in the Lower Ordovician Ontalaunee Formation. Other outcrops show this more extensively, but this outcrop is logistically more feasible for this field trip. Although pressure solution is the dominate deformation mechanism producing tectonic shortening in the carbonate rocks of the Great Valley, both the rocks within and tectonically beneath the Jenny Jump thrust sheet exhibit extensive faulting parallel to bedding. This shearing is commonly, though not exclusively, concentrated in chert rich zones within dolomites. The chert need not be in continuous beds. Zones of nodular chert and very thin stringers appear sufficient to provide a contrast or inhomogeneity in rock strength sufficient to concentrate shearing within these areas.
Although this stop has well developed zones of mylonite concentrated along chert zones that have behaved ductily and show small drag folds (see fig. 7), other outcrops show a transition from brittle to ductile structures in these zones. This transition is achieved through a continual change in the mechanical properties of the rock probably because of the reduced grain size, water weakening or localized frictional heating rather than changes in external parameters such as external temperature and confining pressure. Initially, the dolomite and chert together form a breccia with pieces of dolomite ranging in size from 1·15 cm and pieces of chert ranging in size from 1 mm to 5 cm. Continued shearing pulverizes the chert which then acts as a fine-grained matrix surrounding pieces of dolomite which are still angular and recognizable, yet smaller, pieces of dolomite. At this stage the rock has a "frothy" appearance and the chert has lost its black translucence. More shearing produces a mylonite, such as the example at this stop (see fig. 6), and there are no longer any recognizable pieces of dolomite. Everything has been finely comminuted and the rock has a fluxion structure. At this outcrop the fluxion structure is folded into small drag folds.
It is important to realize that the fluxion structure or "cleavage" developed in these zones does not represent regional cleavage. The orientation of the "cleavage" or mylonitic foliation in these shear zones is related to the original attitude of the chert zones and is parallel to the shear zones. Regionally. this "cleavage" is best developed in narrow shear zones in and immediately beneath the large scale thrusts and is essentially parallel to these thrusts. The Jenny Jump thrust was slightly above the present erosional surface at this stop and may have caused the subsidiary thrusting and mylonitization at this locality.
The Ontelaunee Formation at this stop is very finely to finely crystalline, light to medium gray, medium- to thick-bedded dolomite with thin beds of chert. Fabric information: bedding N. 67° W. 15° NE; extension lineation 13° S 38° E; fold axis in mylonite 14° N 48° E.; joints N 85° E. 67° SE. and N. 15° E. 15° SE.

Outcrop at Jacksonburg Limestone on left.

Sole of Hope Klippe.
Outcrops of Allentown Dolomite on the left. Beds strike. N. 75°, and dip 25° NW. Rocks face up as shown by abundant algal stromatolites.

Outcrops of Allentown Dolomite on left.
Here there are dolorudite beds and orthoquartzite lenses. Big, rounded bedding surfaces suggest algal stromatolites but internal ornamentation is not obvious.

Outcrops of Allentown Dolomite on right.
Rock here is mostly oolite with some oolite matrix conglomerate.

Outcrops of oolitic Allentown Dolomite on right.
Rock has strongly developed extension fractures which strike N.48° E. and dip 65° NW.

Cross small stream
Cross small stream which follows a steep normal fault which fragments the Hope klippe in this area.

STOP 3. Hope klippe of Jenny Jump thrust sheet
Speaker. Avery Drake.
(Park in Methodist Church parking lot on right, unless church services are being held; if services are being held, park on left side of street near Honeywell Hall.)
Here we are on the Bushkill member of the Martinsburg Formation at the northwest border of the Hope klippe. The bounding thrust fault lies in the stream a short distance to the southeast, and carbonate rocks of the klippe crop out on the ridge to the southeast of the streams. The klippe here has been fragmented by a later normal fault which has brought rocks of the Epler Formation into contact with the Bushkill. We will first observe rocks of the Bushkill on the slope to the southeast of Green Chapel Cemetery. The Bushkill here is very disturbed. In the fall of 1978 the following fabric elements could be measured: bedding, N. 30° E., 65° SE. (inverted); slaty-cleavage, N. 20° E., 40° SE.; and pseudo·slaty cleavage, N.38°E. 52°SE.; strain slip cleavage, N. 50°. 45° NW.; intersection of bedding and slaty cleavage and pseudo-slaty cleavage, 20°S.55° W., crenulations, 16° N. 36° E.; extension lineation on slaty cleavage, 38 °S. 50°E.; and a joint, N. 60° W. 60° SW. There are many folds in bedding, but the details have not been worked out. The pseudo-slaty cleavage is thought to result from the emplacement of the Jenny Jump thrust sheet. At this place the planar elements, save the strain-slip cleavage which results from post-klippe emplacement folding, dip beneath the carbonate rocks and the extension lineation plunges beneath them. Bushkill is also exposed in pavement outcrops in the secondary road to the southwest of the Mt. Hermon Road.
After observing the Bushkill, we will examine the outcrops of Epler on the ridge to the southeast. The rock there is finely crystalline to medium crystalline, light gray to medium-gray dolomite which contains thin partings, lenses, and very thin beds of orthoquartzite. The outcrop contains abundant solution collapse breccia. Many of the blocks in the breccia are quite large. Bedding in the outcrop is N. 45° E. 38° NW. A poor fracture cleavage has the altitude N. 10° E. 55° SE. Return to bus and continue northwest on Mt. Hermon road.

Northwest border of Hope klippe.
Cross small stream which marks the northwest border of Hope klippe.

Ramseyburg Member of Martinsburg Fm
Outcrop of Ramseyburg Member of Martinsburg Formation on the left.

Poor outcrops of Ramseyburg on the right.

More poor outcrops of Ramseyburg on the right.

Small pond on right.
Geology along here is obscured by ground moraine.

Outcrops of Ramseyburg on left.

Mangled outcrops of Allentown dolomite
Mangled outcrops of Allentown dolomite of Hope klippe on the left. Continue north .15 mile distance and pull into turn-off on right.

STOP 4: Northwest boundary of Hope klippe
Speaker, Avery Drake.
Here rocks of the Bushkill Member crop out in a cut at road level and carbonate rocks of the klippe crop out on the hill above. This is not a good exposure of the Bushkill, but it is extremely important as the rock here is an auto clastic tectonic melange. Careful observation will reveal phacoids, "tectonic fish" of graywacke and slate, some of which are fold hinges, within the mangled slate matrix (see fig. 8). PLEASE NO HAMMERING OR PLUCKING OF "TECTONIC FISH." There are at least two flat cleavages interlacing within this outcrop, presumably the slaty and pseudo-slaty cleavages viewed elsewhere. The prominent foliation in this outcrop is due E. 10° S.
Here the carbonate rock of the klippe is Allentown Dolomite. The outcrop has a jumbled appearance and bedding is difficult to determine but seems to be about N 10° W., 10° NE. Most of the rock is rather nondescript crystalline dolomite, but there is a fair amount of dolarenite and some oolite, desiccation dolorudite, and dark-gray chert lenses and skims. In addition, some curved forms without internal ornamentation are suggestive of algal stromatolites. It is quite clear at this stop that the carbonate rocks of the klippe lie above the Bushkill. Reboard the bus and continue northeast on Hope Road.

Turn right on Mud Pond Road
Turn right on Mud Pond Road (10,000 pound limit). This road essentially follows a normal fault which has fragmented the Hope klippe in this area, carbonate rocks of the klippe on the right, Martinsburg on the left. Carbonate rock for first .2 mile along road is Rickenbach Dolomite.

Mangled outcrops of Allentown Dolomite on right.

Outcrops of severely mangled Martinsburg.
Rock here is an autoclastic melange consisting of phacoids and lenses of graywacke and slate "swimming" in slate. Extension lineation plunges essentially down the dip of the principal foliation. The klippe sole here lies a few feet up the hill to the right.

Small pond on left.

Good pavement outcrop of Bushkill on the left.

Ramseyburg outcrop on the left.

Slate with graywacke
Outcrops of slate containing a few thin graywacke beds at intersection.

Bridge over small stream.
Bus will go a short distance farther and disembark the field trippers. It will then continue south on Ridgeway Road and turn around wherever possible, and return for the field trip in about 1/2 hour.

This carbonate rock constitutes the small Cooks Pond klippe.
Cooks Pond on the left. Outcrop of cherty, laminated, finely crystalline medium-dark-gray dolomite of the Epler Formation on the right. This carbonate rock constitutes the small Cooks Pond klippe.

Outcrops of Bushkill slate at intersection.

STOP 5: Silver Lake I klippe
Speaker, Peter Lyttle.
The Silver Lake I klippe is a tiny erosional remnant of the Jenny Jump thrust sheet that contains a strongly deformed and perhaps highly telescoped section of Proterozoic granite and Lower paleozoic dolomite (probably Cambrian Leithsville Formation). Although the two or three outcrops that we will examine at this stop may at first glance be a little disappointing, this single locality records much of the tectonic history that we are trying to present on this field trip. We will look at a small ledge of Proterozoic granite that records an early tectonic event of high strain, local mylonitization, and retrograde metamorphism. This first event is interpreted to have occurred during the Taconic orogeny. Later, these same rocks were severely brecciated and comminuted, but not recrystallized (see fig. 9) photomicrograph. Although most of the rock consists of quartz, perthite, and plagioclase, there are minor amounts of magnetite and chlorite that appear to be alteration products of a mafic mineral, probably hornblende. All the minerals, particularly the perthite and quartz are highly strained, brecciated and rotated and severely reduced in grain size. These later structures are interpreted to have been produced during emplacement of the Silver Lake I klippe as part of the much larger Jenny Jump thrust sheet in Alleghanian times.
This small klippe structurally overlies the Middle Ordovician Bushkill Member of the Martinsburg Formation. After the bus picks us up we will head back north along this road passing an outcrop of the Bushkill at the first intersection. At this locality the slaty cleavage dips southeast under the Silver Lake I klippe. South of Stop 5 near Camp Hope (approximately 1/2 mile) the slaty cleavage in the Bushkill dips consistently to the northwest. Therefore, the klippe is sitting in a broad synformal trough of the slaty cleavage. Although it is impossible to prove at this stop, the emplacement of the klippe postdates the formation of the slaty cleavage. We will establish this to the satisfaction of the skeptical field tripper at the last stop of the day, the Grand Union klippe.
The only structures recorded at this stop are a fairly flat mylonitic foliation, N. 16°E. 18° NW. and a steeper and later cleavage N. 78°E. 50° SE. These were both measured (with difficulty) in the highly weathered Proterozoic granite. The pervasive rusty weathering was probably facilitated by the extensive brecciation along the later fracture cleavage. The tiny outcrop of dolomite fractures in a rectilinear fashion no matter how small the pieces become. This may be related to the late fracture sets.

STOP 6: Ebenezer klippe
Speaker. Avery Drake
(At about the Ebenezer sign, the bus will pull off to the right and allow field trippers to disembark. The bus will continue up hill to intersection with Lake Wasigan Road and park. Field trippers will walk up hill examining the outcrops. This will be the lunch stop.).
The first outcrop to examine is just to the north of the small stream, The rock here is Ramseyburg Member of the Martinsburg Formation. Fabric elements measured here in the fall of 1978 include: bedding, N.52° E. 25° NW.; slaty cleavage, N. 48° W. 5°NE.; strain-slip cleavage, N. 25° E. 20° SE,: a joint, N. 44° W. 70° SW.; intersection of bedding and slaty cleavage, 7° N. 48° E.; and extension lineation, 3° N. 35° W. The reader will note that here the bedding, slaty cleavage, and extension lineation have been rotated from their normal southeast dips and plunge so as to dip and plunge beneath the carbonate rocks to the north.
The last outcrop of Ramseyburg is about 400 feet to the north and the first outcrop of the carbonate rock of the klippe is about 375 feet north of there. The rock of the klippe is Allentown Dolomite. There is a particularly good outcrop of Allentown about 225 feet farther north which contains all the characteristic rock types of that unit: algal stromatolites, oolites, dessication dolorudites, etc. The sedimentary structures show that the carbonate rocks face up. The subtle field trippers will have noted that Ramseyburg crops out about 30 feet to the south of this Allentown outcrop for a length of about 20 feet showing that the klippe here, like the Hope klippe, is fragmented by later normal faults. The beds in the Ramseyburg dearly dip beneath the carbonate rocks of the klippe. There are additional good outcrops of Allentown along the road to the east of Lake Wasigan.
We plan to have lunch around Lake Wasigan. This is far from a perfect place, but our choices are limited. Following lunch, board the bus.

Inverted Bushkill slate crops out on the left.

Excellent outcrop of Ramseyburg on the left.
Some beds here are more than 1 m thick.

Rocks here are Martinsburg Fm in the Musconetcong nappe system.

Crossing small stream.
We will cross the trace of the Portland thrust fault within a few feet. Here the slaty cleavage in the Martinsburg is marked by a strong extension lineation which plunges down the dip. The Portland thrust fault frames the very large Paulins Kill window.

Large outcrops of Allentown Dolomite.
These rocks are in the Lyon Station-Paulins Kill nappe which is exposed in the Paulins Kill window.

Allentown Dolomite crops out up Hope Road to the Left.

Outcrops of Allentown Dolomite
Outcrops of Allentown Dolomite in Lyon Station-Paulins Kill nappe on right. Rock is severely deformed, most bedding surfaces have served as fault surfaces. Outcrop is characterized by very abundant filled, northeast-trending extension fractures.

Small outcrop of Allentown Dolomite on knoll to right.

Small outcrop of Allentown Dolomite on right.

Very sandy Allentown Dolomite on right.
Outcrop of very sandy Allentown Dolomite on right. There are abundant orthoquartzite beds here.

Large outcrops of Epler Formation
Large outcrops of Epler Formation on the left. Rocks here include laminated sandy dolomite, laminated dark-gray dololutite, chert-ribbed finely crystalline dolomite, sandy medium to medium-coarse crystalline limestone, and excellent examples of solution collapse breccia. Axes of small folds here plunge 70° S 15° W., down the dip of the beds.

STOP 7 Portland thrust fault
Speaker Avery Drake
(Field trippers will disembark and examine outcrops along road to left. Bus will have to find some means of turning around. There is a small parking area along road to left. This stop is just above the abandoned grade of the New York Susquehanna and Western Railroad. This is a very narrow road and field trippers must use extreme caution.)
The first outcrop to observe is 500 feet along the road to the east. Here are slate outcrops of the uppermost Bushkill Member of the Martinsburg Formation. The slate contains abundant thin beds of graywacke. Fabric elements include: bedding, N. 85° E. 48°SE.; slaty cleavage, N. 72 ° E. 68° SE.; and intersection of bedding and slaty cleavage, 35° S 55° W.
The Portland thrust fault crops out about 375 feet farther to the east.The observations recorded here were made in October 1978 shortly after the road was widened. Winters are particularly hard on exposures in this area and no guarantee can be made as to what the quality of the exposure will be at the time of the field trip. In any case, the Portland fault was found to have the attitude of N.78° E. 48°SE. and the slate above the fault to the east an attitude of N. 80°E. 55° SE. The carbonate rock beneath the fault is thoroughly tectonized. It is mostly medium crystalline, medium-gray dolomite that contains some solution collapse breccia, flat-pebble conglomerate, and dark gray sparry calcite. Judging from stratigraphically lower outcrops of extremely cherty dolomite up the hill to the north, this rock probably belongs to the Ontelaunee Formation. The dolomite contains several movement zones beneath the major thrust which are marked by carbonate mylonite. Extension lineations on the thrust surface plunge 45°S 38° E. Post-thrust strain-slip cleavage has the attitudes of N. 80° E. 40° NW., and post-thrust crenulations plunge 10° S 70° E. There are outcrops of both Ontelaunee and Epler along the road to the east and excellent outcrops of Epler up the hill to the north. We may examine some of these rocks depending on available time. (Board buses and follow unnamed road back up the hill to the north.)

Trace of the Portland thrust fault
Crossing the trace at the Portland thrust fault, the frame of Paulins Kill window.

Inverted Bushkill slate
Outcrop of inverted Bushkill slate at road intersection on the right

Nice outcrops of Ramseyburg on the right.

More nice outcrops of Ramseyburg.
Sedimentation sequences in these rocks begin with a cross-laminated interval which pass up into a planar laminated interval which is overlain by pelite. They are, then Tcde turbidites and belong to turbidite Facies D of Walker and Mutti (1973). The cleavage in these rocks is marked by an extension lineation which plunges 35° S. 15° E.

Outcrops of Bushkill slate on left
Cleavage here is marked by an extension lineation which plunges 20° S. 48° E.

Outcrops of Bushkill slate on the right.
Extension lineation on cleavage here plunges 34° S. 25° E.

Rickenbach Dolomite in the small Alpha Klippe
Rickenbach Dolomite in the small Alpha Klippe crops out to the left. Allentown Dolomite in the even smaller Beta Klippe crops out in the woods about .25 miles to the east-northeast. Both these klippen rest on Ramseyburg and are shown but not labeled on figure 1.

Rock is Bushkill.

STOP 8: Federal Springs thrust fault
Speaker, Avery Drake.
(Follow path to left of stop to reach the grade of the Erie-Lackawanna Railroad. Be extremely careful on the railroad grade, there are occasional trains. Follow railroad grade about 600 feet to west.)
Here are beautiful outcrops of interbedded slate and thin graywacke of the upper Bushkill member of the Martinsburg Formation (see fig. 2). The Ramseyburg Member crops out along the road about 700 feet north of these outcrops. The rock in this outcrop is inverted as shown by sedimentary structures. Fabric elements are: bedding, 50° W. 45° SW.; slaty cleavage, N 70° W, 35° SW.; intersection of bedding and slaty cleavage, 20° S. 35° E., and extension lineation. 28° S. 38° E. Here, the bedding-cleavage intersections which are roughly parallel to the local fold axes plunge southeast beneath the Federal Springs klippe about parallel to the direction of transport as shown by the extension lineations.
Next, the field trip will turn around and follow the railroad tracks to the east. About 400 feet east of the overpass there are horribly mangled outcrops of Bushkill not very far beneath the Federal Springs thrust fault. The field trippers can sort out structures here at their pleasure. The Federal Springs thrust fault crops out about 500 feet farther to the east. The geologic relations at this site are quite complex as it is essentially a quadruple point between Epler Formation, Ontelaunee Formation, Jacksonburg Limestone, and Bushkill Member of the Martinsburg Formation. The Federal Springs thrust fault brings rocks of the Beekmantown Group and Jacksonburg Limestone onto the Bushkill. Two units occur within the Beekmantown here. The lower unit, the Epler Formation consists of very earthy, silty, finely crystalline dolomite that has silty partings, limey dolomite, and some limestone. The Epler is overlain by a unit of medium-gray, medium- to coarsely-crystalline dolomite which based on our experience in Pennsylvania, we assign to the Ontelaunee Formation.
The Jacksonburg Limestone appears to uncomformably overlie both Beekmantown units in these exposures. The Jacksonburg here is a small tectonic sliver of dark gray, shaly cement rock. A sample of this rock contained a poor conodont fauna which, according to John Repetski (written commun., 1979) included the following:
2 drepanodonti form elements, indeterminate, deformed
1 paltodonti form element A
1 paltodonti form element B
Another tectonic sliver of Jacksonburg crops out along the Federal Springs fault about 1100 feet N. 63° E. from this site. The Jacksonburg here is a radically different rock type. being medium-grained calcarenite grainstone. A sample from this site contained as, identified by John Repetski (written commun., 1979) the following conodont fauna:
PANDERODUS
PHRAGMODUS UNDATUS Branson and Mehl
dichognathiform elements
oistodonitform elements
phragmodontiform elements
PLECTODINA
cyrtoniodontiform (N) element
This rather non diagnostic microfauna ranges from the Rocklandian to upper Richmondian. The conodont color alteration index (CAI) of the elements in this sample is 5, indicating host rock temperatures greater than about 290°C.
The structure above the Federal Springs thrust is quite complex. At the end of the railroad cut about 5S0 feet to the east of the fault, Epler crops out at track level. About 65 feet west of this point Ontelaunee is at track level, and about 250 feet farther west Epler comes back down to track level. This rock distribution defines a very tight fold which plunges about 35° N 70° E. Small early folds within this part of the outcrop plunge 35° S 47° E.; essentially parallel to the extension lineation within the Epler. These folds have an S rotation sense when viewed in profile showing that this is an inverted limb. Other fabric elements here include: steep fracture cleavage, due N., N. 80° E.; pressure solution veins which plunge 40° S 20° E., and opens buckle folds in bedding which plunge 10° N 75° E.
Just at the Federal Springs thrust which trends northeast and at these places dips rather steeply, the Jacksonburg Limestone is transposed and the transposition foliation is folded with the rocks of the Beekmantown Group. The fabric elements within the Jacksonburg include: the transposition foliation, N 25° E., 52°NW.; intersection of bedding and slaty cleavage 40° N; 20° W., extension lineation on the transposition foliation, 48° N 40° W.; and axes of small folds in the transportation foliation 10° S 45° W. The lineation formed by the intersection of bedding and cleavage streams around the fold hinge directly above the thrust.
Folds such as those above the thrust are not obvious in the slates of the Bushkill beneath the thrust. The fabric elements in the slate include: bedding, N 75° E 35° NW. (sedimentary structures show that the rock faces up); slaty cleavage. N. 5° W. 35° SW.; fracture cleavage, N. 75° W. 40° SW.; and axes of small folds in slaty cleavage 12° S. 60° W. A wide variety of structures can be observed in the Bushkill to the west of the thrust and the interested observer can observe these at his/her leisure.

More outcrops of Bushkill on right.

Small outcrop of Bushkill on left.

There is a good view of Hunts Pond
There is a good view of Hunts Pond to the right front. We have done no geologic mapping in this area.

Pavement outcrops of Bushkill on the left.

Excellent Bushkill outcrop on the left.

Bushkill outcrop to right, small pond to left.

Bushkill outcrops on the left.

Outcrops of Bushkill on the left.
Here, the slaty cleavage has been rotated past the horizontal and dips northwest. Route 94 is roughly paralleling the geologic strike in this area.

Scattered outcrops of Bushkill along here.
Slaty cleavage dips to the northwest.

Outcrops of Martinsburg Formation on the left

STOP 9: Grand Union klippe
Speaker Avery Drake.
This klippe is a relatively small slab of Allentown dolomite which lies on rocks of the Ramseyburg Member of the Martinsburg Formation. The thrust fault beneath it (fig. 10) was well exposed during excavation for this shopping center. The thrust fault, thought to be the Jenny Jump thrust fault, is roughly parallel to the bedding in the Allentown N. 50° E. 40° NW., and is marked by 1 to 3 inches of gouge as well as by a fair amount of crushed dolomite. The rocks of the klippe face up as is clearly shown by abundant algal stromatolites.
The rocks of the Ramseyburg beneath the thrust are isoclinally folded. The fold trains have a (zigzag) "M" pattern suggesting that the rocks occur in a fold hinge. Bedding immediately adjacent to the thrust is N. 35° E. 65° NW., and it approaches vertical several feet to the southeast (Fig. 10). Slaty cleavage is N. 20° E. 35° NW., has been rotated past the horizontal, and is truncated by the thrust. These data and their geometric relations suggest that the Ramseyburg here is in the brow and upper limb of a northwest-closing recumbent fold. The slaty cleavage is marked by an extension lineation which plunges 39° N 55° W. and extension fractures are N. 38 ° E. 85° SE.
Close examination of the Ramseyburg shows that it, like other Martinsburg we have seen in exposures beneath the Jenny Jump thrust, is an autoclastic melange. Here, most of the graywacke beds have been pulled apart and fragmented and swim as autoclasts in a more slaty matrix.
Two sets of small faults can be seen in the Ramseyburg. One set is
N. 52° E, 40° NW. and has pressure solution veins which show left-separation. The other set is N. 50° E. 80° NW. and shows normal-separations.
This exposure is extremely important as it clearly shows that a klippe of the Jenny Jump thrust sheet was emplaced subsequent to major deformation and slaty cleavage development in rocks of the Martinsburg Formation. This klippe, like the others we have seen, lies in a synform in the slaty cleavage of the Martinsburg.

Large outcrops of Allentown dolomite on right.
This rock is in the Allamuchy nappe.

Good outcrops of Allentown Dolomite on left.

Outcrops of Allentown Dolomite on the right.

Outcrops of Allentown Dolomite behind the Rustic Wine Cellar.

Outcrops of Allentown Dolomite on both sides of road.

Proterozoic rocks at the Allamuchy nappe
Proterozoic rocks at the Allamuchy nappe crop out to the right. The allochthonous nappe-nature of the tectonic unit was confirmed in this area by diamond drilling by the New Jersey Zinc Company (Baum, 1967).

More outcrops of Proterozoic rocks
More outcrops of Proterozoic rocks on the left. We will remain in these rocks until we rejoin Interstate 80.

Outcrops of hornblende granite.
This is Bryam Township, the type area of the so-called Bryam Gneiss.

6: THE NEW JERSEY COASTAL PLAIN
AND ITS RELATIONSHIP WITH THE BALTIMORE CANYON TROUGH
Richard K. Olsson
Department of Geological Sciences
Rutgers University
New Brunswick, New Jersey
Introduction
The coastal plain of New Jersey lies along the western edge of the Baltimore Canyon Trough, a large sedimentary basin which extends along the United States Middle Atlantic states (Fig. 1), The Baltimore Canyon Trough extends seaward beneath the continental shelf to the upper continental slope. A westward extension of the trough forms the Salisbury Embayment of New Jersey, Delaware, Maryland and eastern Virginia. The Raritan Embayment of northern New Jersey and Long Island is a shallow embayment. The South Jersey High separates these two embayments of the trough. The Baltimore Canyon Trough is composed of a seaward-thickening wedge of Mesozoic and Cenozoic sedimentary rocks which overlie a warped and faulted crystalline basement. The sediments that lie within the New Jersey Coastal Plain were deposited west of the main hinge line of deposition. Seaward of the hinge line the sedimentary rocks of the Baltimore Canyon Trough thicken to at least 14 km (Poag, 1979). In contrast the maximum thickness of sediments in the New Jersey Coastal Plain is less than 2 km in tHe Salisbury Embayment.
The sediments in the Baltimore Canyon Trough were initially deposited when North America and Africa separated during early Mesozoic time. The sediments (Figs. 2,3) that accumulated in the Baltimore Canyon Trough consist of limestones, sandstones, sands, shales, and clays (Poag, 1979). Diapir structures noted in geophysical profiles (Grow, 1980; Schlee and Grow, 1980) along the continental slope suggest evaporite deposition occurred in the early phases of continental separation. A deeply buried thick sequence of limestone of Jurassic and Early Cretaceous age is identified in multi-channel seismic reflection profiles of the trough and a carbonate bank or reef thought to represent the lower Cretaceous shelf edge is postulated to lie beneath the present day upper continental slope. Limestones of late Jurassic and early Cretaceous age were penetrated in the basal portion of the COST B-3 well which was drilled on the continental slope off New Jersey. The limestone sequence is confined to the deeper portions of the trough and does not extend beneath New Jersey.
Overlying the limestone sequence (Figs. 2,3) are upper Jurassic and lower Cretaceous nonmarine and shallow marine sandstones and shales (Poag, 1979). These sediments thin beneath New Jersey and lie upon crystalline basement rock. Where penetrated in wells they appear to be nonmarine in character although they have not been thoroughly studied. The upper Cretaceous and Tertiary marine sequence that forms the major part of the New Jersey coastal plain belongs to a marine cycle that began during Aptian time and transgressed over the Atlantic margin, bringing sea level over the New Jersey area for the first time since the Atlantic began to open.
The sediments that were deposited in the coastal plain of New Jersey consist of fluvial sands, gravels, and variegated clays; coastal deposits of beach, lagoon, marsh, and related deposits; inner shelf sediments consisting of shore face sands with characteristic Ophiomorpha trace fossil assemblages and offshore micaceous clay and silty thinly bedded fine sands; mid and outer shelf clay glauconite sands and glauconitic clays, often extensively burrowed; and slope deposits composed of calcareous clays and silts. The formations of these various facies were deposited during major cycles of sea level change and are genetically related to sedimentary units that have been penetrated in the COST B-2 and B-3 wells in the Baltimore Canyon Trough. The relationship of the New Jersey formations to the units penetrated in these wells will be discussed in the section on lithologic units.

6: THE NEW JERSEY COASTAL PLAIN
AND ITS RELATIONSHIP WITH THE BALTIMORE CANYON TROUGH

STOP 1. Raritan Formation overlain by the Pensauken Formation (Pleistocene?).
The sands and clays of the Raritan represent continental and coastal marine sediments deposited adjacent to a transgressing sea. The marine facies of the transgression is encountered in coastal plain wells. The subsurface marine unit is called the Bass River Formation.
Pensauken Formation 5-10 feet
dark yellowish-brown sand and gravel. Large scale steeply dipping cross-beds represent slip faces of fluvial bars. Approximately 50 yds. to the west a fining upward sequence is present. Gravel and lithic fragments are present at contact with Raritan Formation.
Raritan Formation (Woodbridge Member) 65 feet
interbedded sand and clay with numerous siderite and iron oxide cemented sand layers. Two directions of planar cross-bedding can be observed. The cross-bedding probably represents sand waves of a meandering stream or of intertidal currents. Marine fossils are present in some of the sand layers. 30-40 feet.
sand and clay containing abundant carbonized wood. 5 feet.
dark-gray clay and silt, sharp contact with overlying unit. Fine bedding (0.5 mm) composed of clay·silt laminations. 20 feet.
Correlation: Plant fossils and palynological remains in the Raritan indicate a Cenomanian to Turonian (Washita to Eagle Ford) age. Marine fossils (planktonic foraminifera) of a similar age occur in the Bass River marine facies in N.J. coastal plain wells.

STOP 2. Magothy Formation overlain by Pleistocene? sediments.
The Magothy represents estuarine sediments deposited in front of the advancing Merchantville sea. This exposure represents an intertidal sequence of tidal delta sands and lagoonal clays.
Pleistocene? 1 1/2 feet
Sand and gravel
Magothy Formation 45 feet
dark gray sands and clays with carbonaceous rich layers, uniformly cross-bedded sands, intermixed flaser bedding and layers of rip-up clasts. 29 feet.
dark gray laminated clay which laterally on the east side of exposure grades into interbedded sands and clays, carbonaceous rich layers. 8 feet.
dark gray alternating sands and clays. 8 feet.
Correlation: Palynological studies indicated that the Magothy is Santonian in age. This suggests that the Coniacian is absent due to disconformity. This is confirmed in the subsurface on the absence of marine assemblages of Coniacian age.

STOP 3. Woodbury, Merchantville, and Magothy Formations.
The Merchantville Formation represents the second major transgression in the Upper Cretaceous sequence of New Jersey. Subsequent transgressions and regressions of the Cretaceous appear to have fluctuated about the Merchantville strandline.
Woodbury Formation 5-10 feet
dark gray micaceous clayey silt
Merchantville Formation 12 feet
dark gray to greenish black, uniformly bedded sandy silt and clay to sandy clay. Glauconite, mica, and siderite are abundant throughout. Many molds of molluscs are present.
Magothy Formation 8 feet
dark gray alternating fine sand, silt, and silty clay. Rare Ophiomorpha burrows.
Correlation: Ammonite species (Scaphites hippocrepis and others) found in the Merchantville in outcrop date this formation as early Campanian (Taylor) in age. In the sub-surface marine assemblages (planktonic foraminifera) of Santonian (Austin) to early Campanian age are present in the Merchantville thus demonstrating its partial equivalence with the Magothy.

STOP 4. Wenonah Formation overlain by Mt. Laurel, Navesink, and Redbank formations.
The base of the section is exposed in the lower excavation and the upper part is exposed in the higher excavation behind the gymnasium
The sedimentary units at this stop and the next were deposited during a regressive-transgressive-regressive cycle. Bedding characteristics and trace fossil morphology position these units in a marine profile of the transgressive-regressive cycle. See fig. for a composite section.
Redbank Formation (Sandy Hook Member) 15 feet
dark gray, very micaceous; argillaceous, feldspathic, fine quartz sand with disrupted sandy laminae and occasional small-scale cross-laminae. Thick-bedded with mottled texture. Contains sand-filled burrow tubes and the trace fossil Zoophycus.
The above features suggest that the Sandy Hook was deposited in an inner shelf environment not far from the shoreface.
Navesink Formation 20 feet
dark gray clayey, silty, glauconite sand. Burrowed mottled. Contact with the overlying Sandy Hook is gradational. The basal 2 feet of the Navesink contains abundant molds of megafossils and rounded pebbles. Megafossils include large bivalves, gastropods, and phragmacones of belemnites.
The Navesink represents the typical glauconitic shelf facies of the Cretaceous of New Jersey. Paleo-bathymetric indicators (various fossil groups and sediment characteristics) suggest deposition under mid-shelf conditions.
Mt. Laurel Formation 27-33 feet
Thin to medium bedded light gray to white fine to medium sand with thin chocolate brown silt and clay layers. The sand is well-sorted, angular, and slightly glauconitic with dark micaceous laminae. Tabular planar cross-bedding is common in the sand beds. The beds range in thickness from 2-3 inches at the base of the section to 4-6 inches at the top. Maximum thickness is 15 inches. Common broad shallow trough cross-bedding suggests shoreward migration of lunate megaripples. The paleocurrent direction is bimodal, being northwest and southeast. The predominate direction is to the northwest (onshore).
The upper 6 feet is bioturbated and consists of a poorly sorted clayey sand and containing rounded pebbles, abraded fossil molds, and glauconite. Glauconite infills burrows in the upper 3 feet.
Vertical cylindrical burrows of the trace fossil Ophiomorpha and cylindrical to rod-shaped burrows of the trace fossil Asterosoma are present in the lower 20 feet of the section. From about 15-20 feet above the base large robust vertical cylindrical and ellipsoidal horizontal burrows of Ophiomorpha predominate. Thalassinoides also occurs within this interval.
The sedimentary characteristics and the trace fossil associations indicate that the lower 10 feet of the Mt. Laurel Sand was deposited in a transitional zone from offshore (innermost shelf) to shoreface (just below the surf zone). The interval from 10-20 feet above the base represents lower shoreface deposition. The uppermost 6 feet of the Mt. Laurel may be a lag deposit related to deposition of the overlying transgressive Navesink.
Wenonah Formation 8 feet
gray clayey, slightly glauconitic, micaceous, fine quartz sand. Burrowed mottled with indistinguishable bedding. Occasional large clay-filled subvertical burrows (Asterosoma) and Zoophycus
The Wenonah represents an inner shelf facies related to a minor regression prior to the Navesink transgression.

STOP 5. Redbank Formation (Sandy Hook and Shrewsbury Members).
The basal part of the section is exposed behind the Ern Construction Co. and the upper part is exposed above and just beyond in a long excavation.
Continuation of the section from Stop 4. It represents regression shoaling after the Navesink transgression.
Redbank Formation (Shrewsbury Member) 25 + feet
Light gray to white, micaceous, feldspathic, mostly well-sorted fine to medium quartz sand. The lower 10 feet is slightly silty. Occasional thin clay horizons define inclined bedding which represents foreset beds of a prograding sand body. Planar cross-stratification occurs within the foreset beds. Both dip south-westward.
The trace fossil assemblage includes vertical cylindrical and horizontal ellipsoidal Ophiomorpha, rod-shaped Asterosoma, and Chondrites.
Redbank Formation (Sandy Hook Member) 15 feet
Dark gray, very micaceous, argillaceous, feldspathic, fine quartz sand. Mottled texture with sand-filled burrow tubes and the trace fossil Zoophycus. The large light-dark mottled shapes are caused by weathering related permeability

STOP 6. Navesink Fm overlain by Redbank Fm (Sandy Hook Member).
Turn right into parking lot just beyond small bridge. Poricy Park fossil beds area. Walk along path to stream bank.
In contrast to the Navesink at Stop 4, at this locality the formation is richly fossiliferous with skeletal material.
Redbank Formation (Sandy Hook Member) 25 feet
Dark gray, micaceous, feldspathic, fine to medium quartz sand. Glauconitic in the basal part which contains microfossils and small megafossils.
Navesink Formation 15 feet
Greenish-black. clayey glauconite sand. Several shell layers are present. The oysters Exogyra, Pycnodonte, and Ostrea; the brachiopod Choristothyris; and the belemnite Belemnitella are well-preserved and common. Molds of various molluscs are common and an extensive well-preserved epibiont bryozoan fauna is present. Microfossils include foraminifera, ostracodes, coccoliths, and dinoflagellates.

Optional STOP. Type locality of the Tinton Formation
Tinton Falls. Turn left and immediately park by restaurant. Walk behind restaurant.
Type locality of the Tinton Formation, the only indurated unit within the Upper Cretaceous section. The formation is very limited in its geographic extent, disappearing within a short distance along strike to the southwest and in a downdip direction.
Tinton formation 22 feet
Brownish green, argillaceous, quartz and glauconite sandstone interbedded with layers and lenses of gray claystone. Molds of megafossils of gastropods and pelecypods are common. Rare specimens of the ammonite Sphenodiscus occur. A well developed dinoflagellate flora is also present.
The Tinton probably represents an inner shelf facies related to the Redbank regressive facies. It is latest Maestrichtian in age.

STOP 7. Manasquan and Shark River Formations
Stop by dirt road on left. Walk along road to riverbank on the right
Manasquan and Shark River Formations overlain by Piney Point (1) and Kirkwood Formations.
A major disconformity is present here wherein the middle and upper Eocene and the lower Oligocene is missing. More of the Eocene and the Oligocene is encountered in the subsurface, however. Marine deposition that began in the late Cretaceous continued in the early Tertiary. It ended during late Eocene time with a large scale regression. The overlying transgressive Piney Point was deposited under inner shelf conditions on an eroded Eocene surface. The basal Kirkwood is probably a shoreward facies of the Piney Point.
Kirkwood Formation 6-7 feet
Chocolate brown clay 5-6 feet
Piney Point Formation ?
Brown, medium to coarse quartz sand 1 foot
Shark River Formation (Squankum Member) 6 feet
Cream to gray brown, argillaceous, glauconite sand. Upper 1-3 feet indurated. Numerous molds of Molluscan megafossils, plus sharks teeth.

7: COASTAL DYNAMICS AND ENVIRONMENTS ON SANDY HOOK, NEW JERSEY
Norbert P. Psuty and Lindsay Nakashima
Center for Coastal and Environmental Studies
Rutgers University
New Brunswick, New Jersey
George Theokritoff
Department of Geology
Newark, New Jersey
Sandy Hook is a complex and compound recurved barrier spit located at the northern end of the ocean shoreline of New Jersey (Figure 1). The spit is formed from the northerly transport of beach material derived from the erosion of beaches extending approximately 40 kilometers to the south. The shoreline of Sandy Hook consists of several distinct segments with different rates and forms of development. The spit system may be conveniently broken down for analysis into a set of subsystems, each with differing shoreline orientations to the approach of ocean swell and each experiencing different equilibrium conditions. These subsystems, or beach segments are identified on Figure 1 as numbers 1 through 7. Certain beach subsystems may be further divided into subunits, identified by lower case letters on Figure 1. Each of these experiences slightly different shoreline development. These smaller subunits are strongly affected by man-made beach protection structures. The effect of these structures in producing longshore movement of sediment through the spit system is considerable, as revealed in the conspicuous erosion downdrift of the beach protection structures in Segments 1 and 50
The majority of high energy deep water waves approach the region from the east-northeast and east (Saville, 1954). However, wave refraction on the in-shore portion of the continental shelf causes the shallow water waves to approach from the east-southeast (Fairchild, 1966). This region is also subject to the effects of mid-latitude and tropical cyclones, as well as to ocean swell generated by winds far out in the Atlantic Ocean. On the bayside of the spit, the limiting variables of wind speed, duration, and fetch distance favor wave generation from the northwest. Evidence of the importance of these northwest winds is seen in the orientation of bayside beaches perpendicular to this compass direction and also in micro-spit development to the south of these beaches.
The spit platform, delineated by the 6-foot, 12-foot, and 18-foot contours, is the subaqueous extension of the headland beach upon which the spit ridge (beach and dune system), has formed. The platform extends out a considerable distance on the bayside and has a filtering effect on the higher bayside waves during low tide. This condition is most pronounced when strong northwest winds occur. These winds generate high energy waves and blow water out of the bay. During such periods, spilling waves may occur across the width of the shelf and a considerable amount of material may be moved alongshore within this broad surf zone. However, the presence of deep coves downdrift of Segments 4 and 5 prevents significant transfers of sediment between segments by this mechanism. False Hook Shoal appears to be the seaward extension of the spit platform formed by ebb tidal currents passing the distal portion of the spit. This shoal affects wave refraction and thus controls shoreline orientation and beach development on Segments 2 and 3.
Table 1 reveals the magnitude of beach processes within each of the subsystems. Table 2 identifies the amount of shoreline change which occurred within each segment from 1943 to 1972. The two tables reveal that bayside beaches are retrograding at surprisingly high rates. This is due to a reduction in the quantity of sediment being passed to downdrift segments, and to higher wave steepnesses.
The differences in response to changing wave processes on oceanside and bayside beaches at Sandy Hook have been discussed in detail in Nordstrom (1975). It was concluded that bayside beaches (Segments 4 through 7) appeared to be more in equilibrium with storm conditions than oceanside beaches (Segments 1 through 3). Lower bayside wave energies occurring between storms have little effect on profile development, and foreshore slopes inherited from previous storms undergo minor change. There is little or no deposition between storms. The rate of return is too low to provide adequate protection against dune erosion during the next storm, and dune and foreshore erosion will continue. On the oceanside, in contrast, long, high energy, constructive waves occurring between storms rapidly restore the sediment. These deposits provide a buffer zone to protect the beach and dune against the direct attack of storm waves. The net displacement of the shoreline, therefore, is reduced because of the beach recovery between storm periods.

7: COASTAL DYNAMICS AND ENVIRONMENTS ON SANDY HOOK, NEW JERSEY

Entrance gate to Sandy Hook
Entrance gate to Sandy Hook Unit of Gateway National Recreation Area. Proceed straight (north) on Hartshorne Dr. Segment la. Seawall to the right (east) was constructed at the turn of the century and fronts the narrowest portion of the spit.

Northern terminus of a seawall and groin field
Enter parking lot on right (east) and walk out to seawall. Segment 1a. This represents the northern terminus of a seawall and groin field that extends 8.5 miles (14 km) southward. Beaches in this segment are either non-existent or very narrow. High wave energy, a low littoral drift rate, and excessive downdrift erosion combine to produce a negative sediment budget.

Segment 1b.
At this point the road parallels the most critical zone of erosion on Sandy Hook. The beach here is narrow and forms a log-spiral in plan. Recent beach nourishment and sand bag dike operations have been employed as shore protection measures. Note the absence of dunes and the presence of over-wash deposits on left (west) side of the road.

Segment 1b. Site of bath house
Segment 1b. Site of bath house destroyed by storm activity in February, 1978. Parking lot forms on extensive impervious surface which facilitates back-barrier flooding.

Visitors Center
Turn right (east) into National Park Service Visitors Center parking lot and walk out to beach. Segment lb. Regressive log-spiral shoreline of Segment 1b and offset terminus of seawall in Segment la are evident in a southward view. This Segment experiences cyclic beach response and very high erosion rates (Table 2). Ocean swell and wave-induced currents are dominant processes. Sands on the oceanside are well-sorted and medium size. Beach cusps area frequent occurrence. The site of a second bath house lies 100 yards (30 m) to the north.

South Fishing Beach
Bear right (east) on gravel road to South Fishing Beach. Segment 2a. This Segment primarily responds to waves and wave-driven currents, and experiences relatively high storm and swell energies. Backshore features a natural dune belt. Beach is wider than that found in Segment 1.

Battery Gunnison
Enter gravel parking lot on right (east) at Battery Gunnison and walk to beach. Segment 2b. The nearshore in this Segment is characterized by a longshore bar which shelters the beach under high wave conditions. Cyclic beach response is solely associated with major storms. Ocean waves and wave-driven currents are dominant processes. The entire Segment is backed by a natural dune system. The beach north of the timber groin is used as a beach fill borrow area for nourishment of Segment lb.

Lighthouse to the left
Lighthouse to the left (west) marked the terminus of the spit in the 18th century.

Segment 3.
Turn right (east) on gravel road to North Fishing Beach parking lot and walk to beach, Segment 3. This beach is sheltered by longshore bars and False Hook Shoal. Net deposition-occurs in this Segment which is effected by the complex interaction of waves (ocean and bay) and currents (tidal and wave-induced). The shoreline in this Segment is not straight but displays a concave seaward geometry as one walks northward. The tip of the spit exhibits the highest dunes and an ebb shoal which forms False Hook Shoal. Spit growth occurs to the northwest but is limited by annual dredging of Sandy Hook Ship Channel.

Segment 5a.
At this point a seawall fronting large houses (Officer's Row) is visible. Tidal currents and bayside waves are important processes. Bayside Segments possess shore protection structures and deep coves which inhibit sediment transfers to adjacent Segments. The highest bayside waves are experienced here and Segment 4 to the north. Segment 4 lies under jurisdiction of the U.S. Coast Guard and is a restricted area.

This is the terminus of the seawall in Segment 5.
The formation of a log-spiral beach is occurring immediately to the south of the seawall. This Segment is undergoing the greatest amount of erosion due to locally generated swell and storm waves. A peat bed is exposed on the low tide foreshore and a transgressive sequence is forming over the salt marsh deposit. Sediment eroded from this beach is important to development of a spit farther south.

Segment 6a.
The aforementioned accreting spit can be seen to the right (west) across Horseshoe Cove. Wave activity and tidal currents are less important here than other bayside sites. The beach is extremely thin and erosion is threatening the road adjacent to the seawall.

Segments 6a and 6b.
Limited access parking area. This Segment experiences net erosion. Sediments are continuously eroded from behind the timber bulkhead and a deep cove updrift limits input of sediment. The southern extent of this Segment exhibits a small flood tidal delta formed in a breach at Spermacetti Cove. Sediments in this Segment are primarily coarse sands and lag gravels.

Segment 7.
This permits a view of Plum Island and the Shrewsbury River. As would be expected, the lowest wave energies are encountered here. Plum Island is undergoing erosion with accretion occurring at both ends. Such accretion favors formation of a salt marsh habitat. Coarse sands and lag gravels are present. Much of the sediment composing this island is fill, including the land that connects it to Sandy Hook.

8: LANDSCAPE FEATURES AND BOG IRON ORE DEPOSITS OF THE PINE BARRENS
Emily W. B. Russell
Rutgers University
New Brunswick, NJ
Edward Krug
Department of Soils and Crops
Cook College, Rutgers University
Introduction
The New Jersey Pine Barrens, which include the designated Pinelands National Reserve, are a large, unique combination of ecosystems which in general are coextensive with a Tertiary (Miocene) surficial formation, the Cohansey sand (Fig. 1). They thus represent an area where surficial geology exerts a large effect on vegetation. In this general climatic region the natural vegetation is usually deciduous, primarily oak (Quercus spp.) forest (Braun 1950). However, in the Pine Barrens, the forests have a much larger percentage of pines (Pinus spp., esp. P. rigida), in places even to the exclusion of any tree-size oaks. Minor topographic variation plays an important role on the variability within this ecosystem. Lowland forests, mainly of cedar (Chamaecyparis thyoides), pitch pine (Pinus rigida) or hardwoods (Acer rubrum, Nyssa sylvatica, and Magnolia virginiana), grow where the water table is near the surface, and dwarf pines grow on topographical highs, usually on a slightly different geological substratum, the Beacon Hill formation.

8: LANDSCAPE FEATURES AND BOG IRON ORE DEPOSITS OF THE PINE BARRENS

STOP 1. Pedogenic Bog Iron Formations
Pedogenic Bog Iron Formations Of Pigeon Swamp, South Brunswick.
Unmined bog iron site that shows the relationships of podzol soils, surface water quality, and pedogenic bog iron formation. This is posted private land. Viewing of bog iron is best achieved by walking in the stream itself. The south bank of the stream is disturbed by dredgings (parts of this stream were straightened) and by bedding of long-abandoned dirt roads.

STOP 2. Bog Iron Dump, Mount Holly
The remnants of an iron ore dump still exist under two large trees growing at the edge of the North Branch Rancocas Creek, Iron Works Park, Mount Holly. Both lake and bog ores are in these piles. The ores were presumably used by the Mount Holly Iron Works which was destroyed in 1778 by the British Army and never rebuilt.

STOP 3. Water Quality, Soils, And Topography
Water Quality, Soils, And Topographic Relationships To Pedogenic Bog Iron Formation Of Rancocas State Park, Hainesport.
Soils are extremely acidic, pH approximately 4, but are not podzols, the vegetation is typical of that of the Pine Barrens. Water draining this land is clear, not organic stained or rusty, not participating in significant iron cycling. At low tide the relationship of pedogenic bog iron formation to topography is easily observable. River water is the source of iron, the brown river waters coming from the upstream podzols. Shallow groundwaters of the Pine Barrens (podzol zone) are also brown (and ferruginous). Therefore this site is unique in that pedogenic bog iron is visible on the surface because of tides and formed in an area where there is little doubt that the local groundwaters can not supply iron for deposition. This iron deposit is unusual in that ocherous earth forms both above and below the ironstone layer whereas it usually only forms below. This sandwiching effect is probably due to the tidal variation.

STOP 4. Typical pingo
In the middle of the field on the south side of the road is a typical pingo, a common local land feature. Similar structures with raised edges are formed in areas of permanently frozen soils in the Arctic, by a complex process of thawing, erosion and deposition (Tedrow, 1969). The permanently wet center here prevents cultivation and is thus seen by the brush growing there. Pingos appear to have attracted Indians and frequently have artifacts on their raised edges. They may also account for the existence of small bogs where the ground water table is well below the surface, since they are usually underlain by clay lenses.

STOP 5. Harrisville Pond.
This is the site of an old iron works. Evidence for mining of bog iron ore can be seen along the river. Much of the lowland forest here is pitch pine, with a canopy of almost pure pine. The understory is dense and includes many shrubs of the heath family (Ericaceae), for example sheep laurel (Kalmia angustijolia) and blueberry (Vacdnium spp.). These lowland areas occur often along streams with low levees, the same conditions conducive to the formation of bog iron ore.
The Oswego River here has a drainage area of 64 mi2 and discharge of 18.7 in/yr (Pinelands Commission, Draft· Comprehensive Management Plan, June, 1980).
Just up on the left is an exposed soil profile and upland forest. The canopy here is mainly pitch pine (Pinus rigida) but also includes the typical blackjack oak (Quercus marilandica). Tall shrubs are mainly scrub oak (Q. ilicifolia); other prominent shrubs are black huckleberry (Gaylussacia baccata) and lowbush blueberry (Voccinium vacillans). The litter is thin,and scattered where there have been frequent fires. Sandiness and leaching show in the podzol. Without fire the upper humic horizon would be deeper. Below this is the bleached zone. A zone of accumulation of the leached iron and humic compounds may form below this, just above the parent material or Cohansey sand. In places this yellow sand is brought to the surface and deposited on the white sand by ants.

STOP 6 Oswego Lake (Penn State Forest).
There are two types of swamps in this vicinity, hardwood and cedar. Note the pointed tops of the cedar trees (Chamaecyparis thyoides) compared with the flat tops of the pines. The short gradation between these two indicates the small changes in elevation associated with the change from upland to lowland vegetation. The understory here includes highbush blueberry (Vaccinium corymbosum) and swamp azalea (Rhododendron viscosum). In openings the sphagnum moss mat also includes the tiny plants of cranberry (Vaccinium macrocarpon). Both of these species of Vaccinium are grown here commercially.
In places in the cedar swamp, red maple (Acer rubrum) and black gum (Nyssa sylvatica) form an understory which may eventually replace the cedars. Such an area of hardwood swamp can be seen shortly downstream from Oswego Lake. The red maple and black gum are here accompanied by sweet bay (Magnolia virginilma). Continue on past the lake.

STOP 7. Pine Plains
These dwarf forests are the most distinctive feature of the Pine Barrens. There are no other such forests approaching the areal extent of these elsewhere in the world. Stunted, many-trunked blackjack oak and pitch pine dominate the low canopy. Broom crowberry (Corema conradil), a species which reaches its southern geographical limit in the Pine Barrens, is found here. It is a species which probably migrated south along the exposed coastal area during the Pleistocene and has since been isolated from northern populations by the rise in sea level. Note also that the soil here is coarser than in the other upland site, a characteristic of the Pine Plains which may increase dryness and thus fire frequency.

STOP 8. Oyster Creek rest area.
Oyster Creek with 7.43 mi2 of drainage area has a flow of 51.4 in/yr. Compare this with the values for Oswego River. This difference is caused by interbasin transfer of ground water. Much of the water that falls in the Oswego River watershed soaks quickly down into the aquifer below the bed of the river and flows past it, to come to the surface eventually in such streams as Oyster Creek.

9: LATE WISCONSIN-HOLOCENE HISTORY OF
THE LOWER HUDSON REGION:
NEW EVIDENCE FROM THE HACKENSACK
AND HUDSON RIVER VALLEYS
Stephen P. Averill
Fairleigh-Dickinson University
Rutherford, N.J.
and
Pascack Valley Regional High School District
Montvale, New Jersey
Richard R. Pardi and Walter S. Newman,
Radiocarbon Laboratory
Department of Earth and Environmental Sciences
Queens College, City University of New York
Flushing, New York.
Robert J. Dineen
New York State Geological Survey, Museum
Science Service State Education Department
The study area (Fig. 1) is the central and upper Hackensack River valley of northeastern New Jersey and adjacent New York State with reconnaissance study of the surrounding area in Bergen County, N.J. and Rockland County, N.Y. In the text, town names will be in New Jersey unless indicated otherwise. Geologically, the area is the northern portion of the Trias-Jurassic Newark basin where a gently dipping (14°W) homoclinal sequence of Brunswick Formation red sandstones and shales form the deeply scarred bedrock surface. The Palisade sill and basalt lava flows of the Watchungs, interbedded with the Newark series sediments, form prominent topographic ridges in the region. The western slope of the Palisade sill, whose well-studied eastern escarpment forms the Hudson Palisades, is at the eastern margin of the Hackensack Valley. Resistant sandstones of the Newark group form the ridges and cliffs along its western border as well as the divide between it and the parallel drainage system of the Saddle River. The Ramapo fault system slices northeast at the northern terminus of the basin separating it from the rugged Precambrian crystalline mass of the Ramapo Mountain portion of the Appalachian chain. The Hudson River and glaciation have carved an impressive gorge through the Hudson Highlands, The Ramapo River lies in a similar but less spectacular gorge ten miles to the west at Suffern, N.Y. Continental glaciations overdeepened both gorges before overwhelming the Ramapos to push south to their maxima. The deep preglacial Hackensack Valley has been partially overdeepened by glacial ice, then mostly filled by pro-glacial lake sediments (Lovegreen, 1974). The present terrain is gently rolling, with drumlinoidal hills generally aligned north to south paralleling the strike of the bedrock. Essentially glaciation has subdued the preexisting topography, even occasionally reversing it.

9: LATE WISCONSIN-HOLOCENE HISTORY OF
THE LOWER HUDSON REGION:
NEW EVIDENCE FROM THE HACKENSACK
AND HUDSON RIVER VALLEYS

We are crossing the Secaucus drumlin.
It is aligned with its long axis N-S. A relatively thin red till overlies this red and gray rock-cored drumlin. Contact metamorphism of the sandstone was observed throughout most of a very large excavation. The Palisade Sill cannot be far below.

Old Lake Hackensack floor
We are crossing the old Lake Hackensack floor now covered by a 3 to 6 meter sheet of sand with the tidal marsh over the sand. The lake covered the "Meadowlands" as far as one can see. The ridges to the east and west formed the shores.

STOP 1. This is the Rutherford rock-cored drumlin.
The Upper Triassic Brunswick formation sandstones and shales are exposed here at the side of the drumlin. Note the copper mineralization. Red drift, sometimes till, sometimes sand and gravel, blanket the drumlin. Some yellow "loam'" may be exposed (if we're lucky). The "loam" here is about 15'cm thick and is loess. This drumlin was at the western edge of Lk. Hackensack.

Proceeding onto the old lake bed surface.
We are leaving the drumlin and proceeding onto the old lake bed surface. As you drive north on Rt. 17, note what was the steep western shoreline of the lake. A deep preglacial valley exists under Rt. 17. The varves are by far the thickest here along the western side of the Hackensack Valley (Lovegreen, 1974).

Reeds' clay pits for 2550 varves
At the center of the valley close to the Hackensack River are the former brick yard clay pits from which Reeds' extracted and counted 2550 varves.

Sandstone ridge
We are now crossing one of the sandstone ridges that form the low divide between the Hackensack and Passaic valleys.

Near distal end of outwash fan
We have just passed through the divide between the Hackensack and Saddle Rivers and are near the distal end of the outwash fan associated with the Ridgewood kame group. As we proceed north on Rt. 17, notice the slope of the outwash plain.

Northern-most of Lake Hackensack red varves
This is the northern-most known location of Lake Hackensack red varves in the Saddle River valley. (G.S. Pkwy boring records.)

STOP 2. Mastodon display and rest stop.

STOP 3. Crest of the Ridgewood kame group.
Walk back to kame. South side of kame shows stratified drift. This used to be a gravel pit. We are told that much coarser gravel was removed from here than is presently exposed. Return to north side of kame. Clean off the face and note the vertical sand layers with minor asymmetrical folds. At the top of the exposure is a layer of fine to medium sand capped with yellow loess under the top soil and vegetation. Return to bus. <br

STOP 4. Musquapsink Brook
Exposure of red till in the banks to the south. Bedrock in stream to the north.

STOP 5. Woodcliff Lake kame delta
We will have to walk along the causeway. Please watch the traffic. This is the Woodcliff Lake kame delta that built into the proglacial lake in the Musquapsink Valley. Note the very sharp drop in elevation below the dam.

Till capping outwash on the island
As we ride, note the till capping outwash on the island in the lake. It forms a small dark slightly overhanging layer at the top.

STOP 6. Woodcliff Lake reservoir
Enter the Woodcliff Lake reservoir of the Hackensack Water Co. NO TRASH DROPS PLEASE. We will examine the wave-cut cliff exposure of yellow-brown till over readvance outwash. There is less than 1 meter of till here. One-tenth of a mile west, immediately west of Pascack Rd., the tightly packed red cobble till of the Lake Hackensack glaciation lies below the readvance outwash.

STOP 7. Atkins Glen Park
This lovely glen is a preglacial valley (at least pre-Woodfordian) cut across the Brunswick fm. strata at right angles to the bedrock strike. This valley contains red till and near the top is overlain by the yellow-brown till. It is very close to the farthest north natural exposure of the red till. The valley was exhumed in post-glacial time when a large and deep lake left by the ice, in what is now the Bear Swamp section (Park Ridge 7 1/2 minute Quadrangle), was drained by downcutting.

We have crossed into the Saddle River basin.

STOP 8. Side of a Drumlin
Turn RIGHT into gravel surfaced area of pit. It is across the street from the Cemetery of the Ascension. The exposure is in the side of a drumlin. The yellow-brown till is well exposed here. A strong bimodal till fabric can be measured here and fissility of the till was noted in two steep-faced exposures.

STOP 9. The River Vale Road drumlin
The Yellow-Brown till is 2.7-4 meters thick here. Red till is below. View to the east (over golf course) is the line of River Vale kames that form a north-south ridge to the east of River Vale Rd. until they join the Old Tappan moraine at their southern end. The west slope of the Palisades is across the Hackensack Valley in the distance.

Kettle bog areas
We travel through some kettle bog areas before reaching the old (landscaped) kame crest line. The Old Tappan moraine is ahead of us (south). The present reservoir is the location of post-glacial Lake Tappan. Note the ice-pressed terrain on the back-side of the moraine dam. Many large kames were removed from here during construction of the reservoir. Ultimate drainage, resulting in that catastrophic flood, was through the present Hackensack River drainage exit at the dam.

Steep-sided kettle
As we drive up the back slope of the moraine ridge, we can see a steep-sided kettle to the left of the road and just north of the small cemetery.

STOP 10. Old Tappan Rd. and Ledson Parkway
Old Tappan Rd. and Ledson Parkway are on the sandy outwash plain. Erosion has cut a gully here and has revealed the yellow-brown till of the moraine at the base of the ravine.

STOP 11, Observe excavated end of moraine.
It is mostly stratified drift here.

STOP 12. Outwash capped by Tappan till
This is a great sequence of outwash capped by a thin layer of yellow-brown Tappan till. The owner has suddenly died and at this writing we are not sure whether we will be able to enter legally.

STOP 13. Tallman Mt. State Park. Lunch.
After lunch Dineen will discuss the geology of the adjacent Sparkill Gap. Averill will discuss the importance of the Gap to the Woodfordian history of the Hackensack Valley. Newman will discuss the origin of the Piermont salt marsh below and the rise of sea level. For the uninitiated, Dineen and Newman will demonstrate their seismic and coring procedures.

Norwood kame grouping
Road begins to increase in elevation at the Norwood kame grouping and generally runs along the crest.

Norwood kames history
The Norwood kames were constructed into glacial Lake Hackensack and were later buried by the readvance Tappan till glacier.

STOP 14. Kame
Enter new development on north side of road. Walk up hill to top.
Kame is constructed of red coarse cobble outwash and has patches of overlying yellow-brown till.

Outwash plain, then erosional slope
The first slope is the outwash plain. There is then a break in the slope and the slope increases. This is the erosional slope first cut during the drainage of glacial Lake Hackensack.

STOP 15. Mastodon site
This is the Norwood portion of the Oradell Reservoir. This is where the mastodon remains were found. The large (3 meter) diabase boulder can be seen. Discussion....

You are on the outwash plain of the Old Tappan moraine.

Ascending the River Vale collapsed moraine outwash plain.

Incised Pascack Brook to left
Note the flood plain of Pascack Brook to the left (West). It cut deeply into the outwash plain south of the Hillsdale heads-of-outwash.

Going down hill into the area of collapsed moraine.
We have crossed Cleveland Ave. head-of-outwash and are going down hill into the area of collapsed moraine. At the end of Cedar Lane at the "T". is a new Condominium complex. These five story pre-cast concrete structures were built directly on glacial Lake Hackensack red varves. No pre-construction preparation was necessary as they (the varves) were already in a pre-consolidated state.

Crevasse channel outwash feeder
The 1st street on the right (Ruckman Ave.) is the crevasse channel outwash feeder. It can be seen on the left (south) across from Ruckman Ave. It is composed of medium clean sand with occasional large boulders. Piermont Rd. cuts through the crevasse filling in a small stream valley (more on that later).

Everdell Ave. along the crevasse filling.

Kinderkamack Road drumlin
We proceed down the hill to the flat valley floor. Ahead of us is the Kinderkamack Rd. drumlin, one of the largest in the area.

STOP 16. Beechwood Park, Hillsdale, N.J.
Walk into park. Note the kame on the west and the large kettle bog. The bog is also found south of Hillsdale Ave. beyond the confines of the Park. B.P.1 boring was made on the southeast side of the bog and penetrated to the bedrock floor of a deep valley 55 ft. down. Surface elevation of the bog is 50 ft. ASL. B.P.2 was sited 10 m south of Hillsdale Ave. almost due south of B.P.1. B.P.3 was sited east of B.P.2 just east of the sewer cut in the deepest part of the kettle.
Note the stratigraphy as shown in Fig. 10. Discussion.
The Hillsdale head-of-outwash is immediately south of us. A small, apparently very short-lived, proglacial lake formed behind the dam and between the drumlin on the west and the crevasse filling on the east. As the ice retreated, the eastern ridge was breached at Piermont Rd.

Proceed south on the outwash plain of the Hillsdale heads-of-outwash.

The first valley we cross is the Pascack Brook.

Large valley drained by Musquapsink Brook
Farther south, after we pass through "5 Corners" in Westwood, we drop into a very large valley drained by the now tiny Musquapsink Brook. This is the valley cut by the draining of proglacial Lake Musquapsink. The Woodcliff Lake kame delta was constructed into this lake.

Proceeding south in Emerson we are still on the outwash plain.

Oradell drumlin
In Oradell, near the Xerox building, more of the same but on the west is the large Oradell drumlin; rock-cored and coated with red till. Lake Hackensack red varves were encountered at the Xerox site under the outwash sand. Yellow "loam" loess as much as 30 cm thick overlies the area to the south. Man's activity has removed much of the loess.

10: ECONOMIC GEOLOGY:
NEW JERSEY HIGHLANDS
General Introduction and Road Log
Andreas H. Vassiliou
Department of Geological Sciences
Newark, New Jersey
The New Jersey Highlands province comprises the centermost portion of northern New Jersey, extending 96 Km northeasterly across the state and ranging in width from 16 to 40 Km. It is flanked on the northern side by the Valley and Ridge province and on the southern side by the Triassic Lowlands of the Piedmont province. The province, which is part of the Reading Prong of the New Jersey Highlands is essentially a belt of Precambrian crystalline rocks with certain narrow belts of folded and in-faulted Paleozoic sedimentary rocks. The three articles that follow this general introduction contain specific information on these rock types and their relationships.
The Precambrian rocks of the New Jersey Highlands have been hosts to several commercial mineral deposits. Historically, the magnetite iron ore deposits are of unique importance. These deposits have been mined since at least as early as 1710 (Buddington, 1957), perhaps the oldest iron mining in the United States. Geologic and other information concerning the major magnetite deposits of the Highlands was first outlined by Bayley (1910). For several years during the third quarter of the nineteenth century, New Jersey was the biggest producer of iron ore in the United States. Of the 136 mines active in 1880, none are operating today, However, some of the now abandoned mines are still accessible. During this field trip, John Puffer will lead us through two such mines: the Andover-Sulphur Hill Iron Mines (STOP 2) and the Edison Magnetite Deposits (STOP 3).
Interest in the mineralization of the Franklin area has been worldwide and has continued, unabated, for more than a century. In certain rare cases, a significant accumulation of a wide variety of elements is possible in certain areas of the earth's crust, resulting in the formation of a large number of minerals, some of which are unique or exclusive to the area. Kostov (1968) lists only four such localities in the world, with the Franklin area being one of them. The Franklin deposits are enriched mainly in manganese, iron, and zinc, but the combination of the silicate-oxide ore minerals with numerous associated gangue minerals is unique and generally unknown elsewhere. Kushner (1970) compiled an abbreviated manual of Franklin minerals and listed about 200 species. Some of these minerals (e.g., franklinite, zincite, etc.) are either unique to Franklin or are rarely found elsewhere. Today, except for the mining operations at Sterling Hill and at the Farber White Limestone Quarry on Cork Hill Road, all of the mining activities at Franklin have ceased. Bob Metsger, who has been the chief geologist at the Sterling Hill Mine for several years, will lead us through the mine area and describe the occurrence and origin of this classic deposit (STOP 4). Mineral connecting will be available at the mine dump. However, those who are interested may also visit the Trotter and Buckwheat dumps for additional mineral collecting upon payment of a small fee.
The search for uranium in the 1950's is responsible for the greatest metal hunt in the history of the world. The New Jersey Highlands province was included in this hunt, and in 1955 a series of geiger counter hot spots were discovered along the perimeter of a large pegmatite near Cranberry Lake by Mr. Edward Koral and the New Jersey Geological Survey. In 1959 the Byram Exploration Minerals Company put down a vertical shaft on one of the hot spots and named the deposit the Bemco Mine. Throughout the summer of 1959 some uranium was recovered and shipped out (about 95 tons of ore), but the rare earth values of the ore were overlooked at the time. The Bemco Mine, also known as the Charlotte Mine, is located on land now designated as Green Acres and is, of course, inactive. The ore represents a highly unusual mineral assemblage of metamict minerals (e.g. fergusonite, uranothorite, zircon), and is of interest as a good example of hydrothermal mineralization relating to the intrusion of a pegmatite into the metamorphic host rocks. Diamond drill cores studied by Williams (1967) define the ore zone up to a depth of 30 meters. On STOP 1 of the trip, this writer will point out the relationships between the ore and the associated rock units and discuss the origin of the deposit.

10: ECONOMIC GEOLOGY:

STOP 1. Bemco Mine
Led by A. H. Vassiliou
(about one hour). At this point the dirt road has small parking area on the right whose path or trail (uphill) leads to the BEMCO MINE. Go 420 feet along the trail: "sulfide quarry" to the right, downhill. + 840 feet to "red flag" -turn right down the hill to lower trail (about 50 feet).
+ 350 feet, turn left for mine area.
+ 145 feet, to old shaft.
See attached article on the deposit by A.H. Vassiliou.

STOP 2: Andover-Sulphur Hill Iron Mines
Led by J.H. Puffer
(about one hour). Park off road and follow path or trail (right side of road) to ANDOVER-SULPHUR HILL IRON MINES. See attached article by J.H. Puffer.
You will be asked to sign a waiver before entering the mine property, and are requested to wear a hard hat and safety glasses. Follow the path from the mine gate to an open clearing. The Andover Mine workings including adit portals and an open pit are found along a cliff located south of the central clearing. Highly altered diabase dikes are intruded along the cliff. The diabase is black to dark green, highly chloritized, fine grained rock that has been sheared and mylonitized. The magnetite ore is disseminated in a light gray Quartz-Oligoclase Gneiss. Dark green pyroxene-feldspar gneiss is exposed above the cliff east of the mine. The pyroxene-feldspar gneiss is green (highly epidotized) fine grained, migmatitic, locally calcareous rock. The pyroxene component is diopside. A light buff microcline granite gneiss is exposed along the road just west of the mine.
The Sulphur Hill open pit is located about 400 feet north of the central clearing. The pits are dangerous and are closed to visitors. Most of the rocks found in dumps at the north and eastern edges of the clearing are from the Sulphur Hill Mine. The rock is a magnetite and sulphide rich garnet skarn. Amphibolite is exposed south of the Sulphur Hill Mine. It is recognized by its black hornblende content, and is coarser grained than the pyroxene-feldspar gneiss.

STOP 3: Edison Magnetite Deposit
Led by J.H. Puffer
(about 30 minutes). Park off road (clear area on right). Climb up bank, cross fence, to the EDISON MINE magnetite deposit. See attached article by J. H. Puffer.
Buses will turn around. At the southern end of the open pit (The Old Ogden Mine) there are good exposures of a biotite, sillimanite and magnetite rich phase of a metasedimentary Quartz-Potassium Feldspar Gneiss. Sulfides including pyrite, chalcopyrite, and molybdenite are disseminated throughout the rock but are found concentrated near the south-east corner of the pit. Acid solutions leached through the sulfides have accelerated the alteration of the rock to a sericite rich saprolite. Please exercise extreme caution when approaching the open pit, and be on the alert for poison ivy.

STOP 4. The Sterling Hill Mine, Ogdensburg
Led by R. Metsger.
Here we shall have lunch, go on a mine tour, and then do some mineral collecting at the dump. See attached article on the deposit by R. Metsger.

11: ENVIRONMENTAL GEOLOGY OF THE HACKENSACK MEADOWLANDS
Sam L. Agron
Newark, New Jersey
This trip to the Hackensack Meadowlands District has several purposes:
1. To observe the natural environment of the Meadowlands, the problems and challenges it poses, and to gain some understanding of how the geologic history gave rise to that environment.
2. To see how numerous, complex, diverse, and seemingly incompatible land uses can be carried out harmoniously and profitably if a region's geology and ecology are adequately understood by planners; and if imaginative engineering, political and economic planning are applied.
3. To inspect several of the major projects that have been erected in the Meadowlands, consider their operational processes and how they impact on the environment and, above all, how geologic constraints were dealt with in designing foundations, etc.
The pioneering work done by the Hackensack Meadowlands Development Commission in planning and overseeing the harmonious growth of the District is unique in this country. A long-blighted area, where land was almost worthless some four decades ago, now contains some of the most valuable acreage in the country. What can be learned here may very well have application elsewhere.

11: ENVIRONMENTAL GEOLOGY OF THE HACKENSACK MEADOWLANDS

West margin of Hackensack Meadowlands.
Schuyler Avenue which follows bluff marking west margin of Hackensack Meadowlands.

STOP 1. (Kearny) Overlook, south end of the Meadowlands.
Panorama (left to right) shows sanitary landfills, more than 100 feet in elevation, over which the first section of the De Korte State Park will be erected; the New York City skyline including the World Trade Center towers (about 7 miles distant); Snake Hill; New Jersey Turnpike; Pulaski Skyway (Routes 1 and 9); and the Bayonne Bridge arch to Staten Island. The southern boundary of the Hackensack Meadowlands District, which is under the jurisdiction of the Hackensack Meadowlands Development Commission, lies about 1/2 mile north of the Pulaski Skyway. The meadowland environment continues south of the District boundary.

Belleville Turnpike descends into Meadow lands.

STOP 2. Tour of HMDC Solid Waste Baling Facility
See text above.

STOP 3. (North Arlington) Schuyler copper mine.
This is the approximate location of the Schuyler copper mine. The shaft was a couple of hundred feet to the NW. The mine was discovered about 1719 and was probably the first copper mine in the United States. It shipped 110 casks of ore from New York in 1721 (Lewis, 1907). Much detailed historical information can be found in Woodward (1944).
The mine was a source of considerable wealth before the Revolutionary War and continued to be worked intermittently until 1865. The primary ore mineral, chalcocite, occurs in unaltered gray arkosic sandstone overlain by red shale and intruded by small, irregular basalt dikes. The major secondary mineral is the bluish-green copper silicate chrysocolla which penetrates the rock along joints and bedding planes.

STOP 4. Panorama of the Meadowlands
Fig. 20 Looking E from Schuyler Ave. (near Carrie Rd.), North Arlington to wetlands in Lyndhurst, N.J. Kingsland Creek, in middle, flows towards the Hackensack River. To the right are landfills and the Sawmill Creek Wildlife Management area.
Overlook showing a panorama of the Meadowlands N of the one in Stop 1. Kingsland Creek, in the foreground (Fig. 20), lies towards the N end of the Sawmill Creek Wildlife Management Area (Fig. 13). The panorama from left to right shows the Meadowlands Racetrack, Giants Stadium, and the Arena; sanitary landfill; twin towers at S end of the Harmon Cove development; Empire State building and mid-town Manhattan skyline behind the Palisades ridge, sanitary landfill, World Trade Center towers are almost in line with Kingsland Creek. The W spur of the N. J . Turnpike is in the middle distance; the E spur passes behind Snake Hill, at the right. Note the wetland dikes.

Descend to Meadowlands.

Copper mine exploration shafts
Bricked-up entrance to copper mine exploration shafts in red beds behind Kuttner Prints plant on left. This is the Lyndhurst Office Industrial Park, one of 11 industrial parks in the Meadowlands. This park includes the Meadowlands Corporate Center and tenants such as Peugeot, Citroen, etc.

Polito Ave. has developed a "wash board" effect
Polito Ave. has developed a "wash board" effect because the road was built directly on the meadow mat, which doesn't support the heavy truck traffic very well.

Cross Berry's Creek.
The very serious mercury pollution problem in Berry's Creek and its environs originated in an industrial plant about 3 miles upstream (see text above). The Creek forms the W boundary of the Meadowlands Sports Complex. whose three major structure loom large on the left.

STOP 5. Meadowlands Sports Complex
(Note: Mileage and routing directions to parking site will be made available by the Sports Authority at time of the trip).

STOP 6. Sewage Treatment Plant
Tour of the plant and new construction in progress. See text above. Opposite this stop, across the Hackensack River in Ridgefield Park, is the Bergen generating station of Public Service Electric and Gas Company (Fig. 21). This plant is in the extreme northeast corner of the Hackensack Meadowlands District. It is a conventional oil-burning power plant, but is also equipped to use coal and natural gas. In 1983 it will also burn garbage from the resource recovery plant to be constructed adjacent to it by Bergen County (Boyd, 1980d). Procedures are employed to minimize thermal pollution of the Hackensack River, to condense spent steam from the turbines for reuse in the boiler.
Several ponds to the northwest of the Sewage treatment plant were clay pits. Little Falls was once the center of a major brick-manufacturing industry.

Two LNG storage tanks to the east

STOP 7. Stone pier S of Sky Harbor Marina
Walk to end of pier for view of Hackensack River (Fig, 22). Sand and gravel storage facility can be seen on opposite (E) shore of the river. in Secaucus. Route 3 bridges cross the river to south. Behind bridge is the Harmon Cove development, our next stop.
Two LNG storage tanks can be seen about 0.7 mile to the NE very close to a superhighway (Fig. 23). Most of the area between here and the tanks has been rezoned for residential use. See text above.

Bridge crossing Hackensack River.
Harmon Cove development on the right.

STOP 8. Harmon Cove Development
Harmon Cove Deve!opment, Hartz Mountain Industries. Secaucus. See text above.
We will leave the bus here and board it at the Twin Towers high-rise condominium at the south end of the development. Start walking along the bicycle and jogging path that winds southward through the area of town houses that stand between Meadowlands Parkway and the Hackensack River (Fig. 24). The top of the 25-story Twin Towers affords a spectacular view of the entire Hackensack Meadowlands District lying on the floor of post-glacial Lake Hackensack. The Manhattan skyline looms impressively beyond the back slope of the Palisades, which marks the eastern border of the District. The Hackensack River can be seen as the central artery sustaining the watery ebb and flow of estuarine life in the wetland habitat. The network of highways includes the Pulaski Skyway, East and West Spurs of the New Jersey Turnpike, Rte. 3, and others. Five highway bridges and six railroad bridges cross the Hackensack River in the District. Landfills towards the SW mark the site of the De Korte State Park. To the north can be seen the Sports Complex, the LNG storage tanks and the PSE & G electric generating plant. Another power plant is at the far south end of the area. Several industrial parks are distributed throughout the District.

Secaucus water tower on right.
The town of Secaucus forms two "islands" inside the Hackensack Meadowlands District (Fig. 6). Its location was determined by the presence of bedrock at the surface, which posed none of the foundation problems found elsewhere in the Meadowlands.

Little Snake Hill on left.

Snake Hill (Big Laurel Hill) on right.
These are diabase plugs which may have served as vents or feeders for the Watchung lava flows. Snake Hill has been largely quarried out for trap rock crushed for use as road metal. It supplied crushed stone for Hartz Mountain Industries. Snake Hill is zoned for residential use (Fig. 4). Because the basalt provides an excellent foundation housing can be built more cheaply here than at Harmon Cove or elsewhere in the District where costly pilings must be used. Low-cost housing has been suggested for the site because the cost per unit would be lower. The site's isolation, however, mitigates against this type of housing.

Sawmill Creek Wildlife Management Area
Sawmill Creek Wildlife Management Area to the right (Fig. 2). This will be part of the De Korte State Park.

12: ENVIRONMENTAL GEOLOGIC TRAVERSE
JOSEPH A. FISCHER
Fees Geosciences Inc., Meyersville, New Jersey
GENERAL CONCEPT
Initially, this trip was going to include a number of stops in the Appalachian Fold Belt, the Highlands, the Newark Basin, the Coastal Plain and right down to New Jersey's barrier beaches. As the detailed plans began to take form, there appeared to be no way to sample in one day, all the varieties of geology that New Jersey has to offer unless one did it from a speeding helicopter. Thus, the route shown on Figure 1 attempts to sample as many different geological environments and concurrent geologic problems as can be "shoved" into a single field trip.
A total of 10 stops are planned (as shown on Figure 1). These are:
1. Route 280 West Orange, road cuts in the First and Second Watchungs;
2. Ridgedale Avenue, Morristown, terminal moraine -- semi-abandoned quarry;
3. Route 202 South of Morristown, Ramapo Fault, hospital across "active" fault;
4. Great Swamp, problems of managing 6,000 acres of wildlife preserve in a suburban environment and how the refuge affects its surroundings;
5. Millington Gorge -- faulted (or erosional) cut through Second Watchung, flooding concerns;
6. Millington Quarry -- blasting and transportation of trap rock in a middle class suburban environment;
7. Bridgewater Township-Route 78 road "cuts" in Second Watchung Mountain, compare with Stop 1;
8. Far Hills -- -Where does the Ramapo go?
9. Bernards Township/Bedminster, proposed 1,500 acre development, variable soil and rock, mostly impermeable soils, mostly shallow rock -- how do you build a new "town"?;
10 . Berkeley Heights -- Whither goest Route 78?

12: ENVIRONMENTAL GEOLOGIC TRAVERSE

STOP 1. First Watchung
Rather than a stop, this will be a slow drive by (either by direction or limitations of the bus). As the elevation rises from the Northfield Road (State Route 508) intersection with Route 280, the first outcrops seen are of the Brunswick Formation (sandstones). Then Route 280 climbs into a major road cut within the Watchung basalts (First Watchung). The basalt cut is steep and the blocky, columnar structure of the lower basalt can be observed early. At higher elevations, the cut is in ropey and pillow lava. Along the cut in the Second Watchung, while it is still at a high angle, several failures can be observed along minor shear zones in columnar basalt. (see Manspeizer, and Olsen this fieldbook).

Second Watchung
Note Riker Hill to the west as 280W descends to the area of Glacial Lake Passaic . Along the cut in the Second Watchung, while it is still at a high angle, several failures can be observed along minor shear zones in columnar basalt. (see Manspeizer, and Olsen this fieldbook).

Glacial Lake Passaic

New Jersey Highlands to the west
Traversing glacial deposits overlying Brunswick Formation.

STOP 2. Abandoned Quarry
This is a semi-abandoned quarry. The main purpose is to observe the materials in the terminal moraine at this point. At this location, the embankment is primarily sand.

STOP 3. Morristown Memorial Hospital - On Ramapo Fault
Ramapo Fault - Highlands immediately west of road
Is it or isn't it an active fault? If it is active, how active?
Lamont-Doherty Geologic Observatory has indicated it is a capable* fault. The technical and judicial examiners on the recent (1977) Indian Point Nuclear Power Plant Appeal Board hearings declared it was not. The Nuclear Regulatory Commission and Consolidated Edison Co. consultants agree with the hearing board.
Controversy still rages with the planning of two water supply dams across the fault in southern Rockland County. Intervenor witnesses have quoted an April 1978 Science article (see References) concerning the Indian Point plants as their rationale for requesting a seismic factor even greater than that used in design of the nuclear plants across the Hudson River.
Yet here in New Jersey, there are hospitals and schools built across the fault in two towns we will pass through on this field trip -- Morristown and Bernardsville. No controversy seems to exist in this area of the state concerning the activity of the Ramapo, despite experiencing a Mag. 3.1 earthquake in Bernardsville as recently as March 10, 1979,
At this stop we'll quickly look at the "fault" as it passes below a hospital. Is it disaster waiting to happen or is it a tempest-in-a-teapot? Look at the trace here in Morristown. The trip will pass over the Ramapo and related structures several times. The seismicity of the Ramapo will be discussed at Stop 4 (in greater comfort).
* 10CFR 100 Appendix A, Seismic and Geologic Siting Criteria for Nuclear Power Plants.

Route 202 generally lies along Ramapo Fault.
Notice new construction, homes, apartments, office buildings. Some are on septic systems; some are on Morristown sewage treatment plant system.

Descend to Glacial Lake Passaic terrain
Outlier of Third Watchung basalt flow to the north and Long Hill (third flow) to south.

STOP 4. Great Swamp Refuge (lunch)
The Great Swamp Refuge was established in 1960. It is only 26 miles west of New YorK City in the Boston-Washington metropolitan corridor. It is approximately 6,000 acres of swamp woodland, hardwood ridges, grass lands, old croplands, and water impoundments. As previously noted, it is within a portion of the area covered by ancient Lake Passaic.
Approximately two thirds of the refuge is designated as Wilderness Area and the remainder as Management Area. Man-made structures and motorized vehicles and equipment are prohibited by law from this area. In the Management Area, the habitat is controlled by cutting brush and timber, mowing, farming, planting shrubs, regulating water levels, and by providing nesting structures.
The problems of maintaining a wildlife refuge in an area where population and commerce are steadily growing will be discussed by members of the Refuge staff.

Rise from Glacial Lake to Long Hill basalts

STOP 5. Millington Gorge (gorge in basalt)
This steep-sided cut through Long Hill (the Third Watchung) is aligned with Osborne Pond in Basking Ridge and Mt. Kemble Lake in Harding Township as well as a valley through a ring of basalt in the New Vernon area. Is this an en-echelon fault of the main branch of the Ramapo or just differential erosion and coincidence?
Whatever the reason, during heavy storms the Gorge acts as a constraint to flow in the Passaic ponding water as far upstream as the Great Swamp and contributing to many flooded basements to the north (see Figure 1) along Black Brook and the Passaic River.

STOP 6. Millington Quarry (quarry in basalt)
At the time of preparing this outline, it was not known whether we would be allowed within the Quarry or would have to walk from Millington Gorge to view the scope of the operation. The concern here is not the mere idea of quarrying the Watchung basalts, which are well exposed in the Gorge and many other locations for inspection, but in blasting rock and the resulting transportation in a middle-class, suburban environment. The quarry has continually been in litigation with the town because of the noise, dust and shaking caused by trucking and blasting operations.
Present New Jersey State law requires that a peak particle velocity of two inches per second should not be exceeded in critical areas away from any blasting. Whenever checked, the quarry has not exceeded these limits yet the complaints continue, not unexpected as the human body is an excellent vibration device, The present N.J. criteria were derived from work undertaken in the 1960's by the U.S. Bureau of Mines with subsequent confirmation (?) by others in Sweden, Canada and Great Britain. The presently proposed Bureau of Mines criterion is a particle velocity of one inch per second. What will these criteria do to quarries like this and others in similar environment? The proposed criteria also establish air blast limitations.
We'll discuss all of the above.

Shallow Brunswick

Shallow Brunswick to basalts, Second Watchung

STOP 7. Scenic View Parking Area on Second Watchung
Can view road cut best from east end of Parking Area. View to the west is across Newark Basin to New Jersey Highlands
Two possibilities exist for the problems as encountered at this highway cut. One is that a fault zone cut through the basalt in this area; the other is that merely the broken columnar nature of the rock here made steep rock cuts impossible. The embankments at this location were cut originally at the same slopes as the remainder of the highway. Repairs kept the highway closed for over a year while the pavement was otherwise completed. After a long period of cogitation, the slopes were cut back to what you see at present. Rock falls were minimized and the ten miles of highway opened. The additional costs of time and excavating are not known but must have been considerable. Could a good site investigation have prevented this problem? -- a discussion.

Descend from Second Watchung

Probably Brunswick mudstone
Probably Brunswick mudstone with perhaps some more conglomeratic facies toward Highlands to the west

STOP 8. N.J. Highlands to West, Ramapo Fault bends to west.
At Far Hills, we can compare the mapped location of the Ramapo (See Figure 1) with the local topography and discuss the effect of the fault upon local construction, both socially and from a general ground water viewpoint.

Leonard J. Buck Gardens
The proposed (Spring 1980) Somerset County Arboretum is at Moggy Hollow. A bit of New Jersey geologic history will be retained.

STOP 9. Johns Manville Properties site
Development of New Town-Bernards Township/Bedminster
A new development comprised of housing and office buildings is planned for a 1,500 acre site. The site was in litigation for several years and the decisions in the two townships were totally different (and will be discussed). Some 400 acres (higher density - Bedminster) will be sewered while 1,100 acres (low density - Bernards Township) will be on individual or small combined septic systems.
The site has shallow basalts and shales, residual soils, lacustrine deposits, glacial till, high water table, protected streams, steep slopes and is adjacent to the Ramapo Fault. How do you develop this property (the largest single site planned for development in New Jersey)? We'll have a local geology map, test this pit data, percolation test data and some development concepts for discussion -- a seminar.

STOP 10 Route 78 - Berkeley Heights
The highway has been completed to this location for some 5 to 10 years. The road has opened in 1978 from Millburn to Newark Airport (see Figure 1) but there has been extensive discussion concerning the most environmentally sound route (or non-route). We'll discuss it a little more, from primarily a geologic viewpoint.

13: THE PASSAIC RIVER FLOOD PLAIN AND BASIN IN NEW JERSEY
JOSEPH WEISBERG & JOHN MARCHISIN
Department of Geoscience/Geography
Jersey City State College
The field experience follows parts of the Passaic River and its tributaries beginning at the Newark Campus of Rutgers University. The trip parallels the course of the River. It then continues along U.S. Route 46 West to Wayne, Oakland, Lincoln Park and Fairfield in Passaic and Essex Counties near the confluence of the major tributaries; the Pequannock, Ramapo and Pompton Rivers and returns to Newark.
The Passaic River Basin
Created during the Wisconsin age, the present drainage basin of the Passaic River trends in a generally east-to-southeast direction in the Passaic-Essex County Region. The River, rising in Mendham Township, N.J. in Morris County, receives major tributaries as the Saddle River, Mahwah River, Third River, Rockaway River, Whippany River, Pequannock River, Pompton River, Ramapo River, and Wanaque River. All these tributaries drain a natural retention basin formed in the swamp made up of the Black Brook, Troy, Little Piece and Great Piece Meadows. These are part of the remnants of ancient Lake Passaic formed as an impoundment when the Wisconsin glacial advance closed a water gap at Short Hills and subsequently opened another in the Little Falls-Great Notch area.

13: THE PASSAIC RIVER FLOOD PLAIN AND BASIN IN NEW JERSEY

Note debris build-up and desnagging needed.

Dundee Dam
Dundee Dam is the area of demarcation between fresh water above and estuary below Garfield.

STOP 1. Great Notch
The roadway is located in an area that was formerly one of two spillways. The lithology is a basaltic flow of the First Watchung Mountain. This is the second water gap opened at the close of the Wisconsin glaciation.

Junction of Singac Brook and the Pompton River

STOP 2. Weir and flood marker
Weir and flood marker are located at the junction of the Pequannock and Pompton Rivers. Note the bar deposits due to the curtailment of the stream energy by the bridge and pipeline. In this area the watershed traverses a setting of homes and ball fields. Return to bridge, proceed right on Pompton Plains Cross Road.

STOP 3 Intersection of Cross Road and Framingdale Ave
Old Feeder Dam above junction of the Pequannock and Pompton Rivers. Note changeable sign that keeps drowning record. This is a region of severe flooding after heavy rainfall despite the canal that can be followed from this region to Stop Two.

First Watchung flow on right
The ridge on the right is part of the First Watchung flow. Drainage on this side runs toward Pompton Lake, opposite is Wayne Township.

Pompton Lake
Long term siltation and eutrophication has affected the retention ability of the lake. Dredging is to begin in mid-1980. Evidence of an abortive landfill can be seen in part of the lake shore along Rt. 202N.

STOP 4. Upper end of Terhune Park
This location is at the upper end of Terhune Park on Pompton Lake which receives the Ramapo River. It is named for Albert Payson Terhune, a dog breeder and author. It is also the site of boxer Joe Louis's training camp during the 1940's. Residential development lies on both sides of the river; note the undercutting of the retention wall. The area is connected by a small bridge to elevated Rt. 202N where residents park cars prior to flood events. Similar bridges can be found east of this location. A major problem is that the flood plain is swamp woodland resulting in debris jams at many sites.

STOP 5. Newark's Wanaque Reservoir pump station
Newark's Wanaque Reservoir pumping station has a persistent desnagging problem. The Ramapo Fault lies under the talus sloop (north) seen across the lake dam at the pumping station site.

Turn right over the Bridge at Dawes Highway.
The Pompton River forms a meander near its junction with the Pequannock River. Two to four feet of water inundate four blocks of homes during severe flooding.

STOP 6. Sewage Treatment Plant?
2011: There is no description for STOP 6 in the Guidebook. The directions, to go left on Riveredge Drive, take you near here. -- OHM

Sand and gravel pits
Note the sand and gravel pits associated with the Wisconsin glacial moraine. Rt. 23 dips in several locations leading to major flooding following heavy rain, especially near the sites of the Racquetball Spa and MacDonald's Beach and Lake adjacent to the road.

Drainage Ditch
Note the drainage ditch that now enhances flooding near the elevated cottages.

STOP 7. Bridge at Riverside Drive.
The bridge and pipeline are part of the water supply for the city of Newark. The siltation and build up of, debris occur in several locations in a limited area.

STOP 8 Dorsa Ave.
Dorsa Ave. is the designated flood parking area, for area residents. Pia Costa Co. property is a natural retention basin extending into Fairfield, now being developed near Rt. 46E at opposite side of the basin. The railroad trestle shows much evidence of heavy siltation.

STOP 9. Park at Soccer Field.
Note Pompton River undercutting banks and homes with retaining walls opposite the fields. This is Lincoln Park, the site of repeated flood problems during heavy rainfall. The soccer fields have been flooded to a depth of 3-4 feet during flood stage of the river. Make a U-turn in parking lot and return to the Newark-Pompton Turnpike. This road follows part of the flood evacuation route to emergency parking.

Pompton River
Fairfield Rd. follows the course of the Pompton River. Elevated homes are built on the island and opposite bank. Raised bridges create access to the sites of housing.

STOP 10. Two Bridges
This is the junction of the Passaic and Pompton Rivers, a site of frequent flooding after heavy rain. Color differences noting the river junction is often obvious at the bridge junction.

Riverside Drive.
Proceed to Riverside Drive. Homes built on the flood way of the Passaic River between it and a former retention site. Minor flooding occurred with frequency prior to the development of the retention site.

STOP 11. Willowbrook Mall.
A mall developed on the former retention area elevated the region. The homes near Riverside Drive now receive drainage from this parking lot and flood water from the river. Flooding is more frequent and severe. The roadway is township property and not mall property and is designated a flood parking area.

14: LATE TRIASSIC PART OF NEWARK
SUPERGROUP, DELAWARE RIVER SECTION
F.B. VAN HOUTEN
Department of Geological and Geophysical Sciences
Princeton University, Princeton, New Jersey
The Late Triassic part of the Newark Supergroup exposed along the Delaware Valley (Van Houten, 1969) consists of as much as 6 km of nonmarine sedimentary rocks and an associated sill. Its strike generally parallels the northeasterly trend of the basin with a dip of 10-20°NW. Along the northwestern margin the sequence is bounded by Precambrian and Paleozoic rocks of the Reading Prong of the New England Upland. Most of this boundary is a system of high-angle faults (see Ratcliffe, this guidebook), but intermittently Newark border conglomerate overlaps on rocks of the upland terrane. Within the basin and along its southeastern margin Newark strata lie on Paleozoic and Precambrian rocks of the Blue Ridge and Piedmont provinces.
In the northeast (Fig. 3) the Newark Supergroup consists of a lower, locally conglomeratic Stockton Arkose (1840 m, 6000 ft), grading upward into reddish-brown Brunswick Mudstone (more than 1900 m and perhaps as much as 4000 m thick). Along the northwestern faulted border these deposits interfinger with the Hammer Creek Conglomerate. In the central part of the basin the widely-occurring Stockton and Brunswick formations are separated by and interfinger with the dark gray to reddish-brown Lockatong Formation (as much as 1145 m, 3750 ft thick). These major sedimentary rock types comprise rather uniform, widespread units. In the Delaware Valley area a diabase (dolerite) sill is intruded into Lockatong and lower Brunswick strata.
Across the central part of the basin, as seen along the Delaware River, the Newark formations are repeated in three large northwest-tilted blocks. The Flemington and Hopewell faults that bound them may be part of a transcurrent system involving those along the northwestern border as well. Geophysical and subsurface evidence of intrabasin faults near the present margin of the basin (Summer, 1977; Cloos and Pettijohn, 1973) indicates that it was not a simple half-graben.
The Newark Supergroup ranges in age from Karnian (Late Triassic, 215 my) to late Liassic (about 180 my), with Liassic sedimentation beginning about 100 m below the 1st Watchung basaltic lava flow in the middle of the Brunswick Formation (Cornet and Traverse, 1975; Olsen and others, 1980; Olsen, this guidebook). Along the terrane of extension in eastern North America basin development and igneous activity apparently peaked about 190 my ago. In the Delaware River section the Triassic-Liassic boundary presumably is above the preserved Brunswick strata.
FIELD TRIP
Route and Objective
This one-day field trip (Fig. 3) crosses the Newark Basin and Watchung lava flows northwestward from Newark to the border fault, then turns southwestward to the Delaware River section of the Newark Supergroup in the northernmost of three major fault blocks in the central part of the basin. Stops along the 33 km (20 mi.) traverse southward down the section afford study of 1) the Hammer Creek Conglomerate near the northern border fault, composed of Paleozoic carbonate and quartzite clasts in fining-upward sequences marked by calcrete paleosols; 2) the lower part of the Brunswick Mudstone arranged in repeated alternations of reddish~ brown silty mudstone and claystone mudflat deposits; 3) the cyclic lacustrine facies of the analcime-dolomite-rich Lockatong Argillite and its hornfels; 4) the small Byram diabase sill; and 5) the Stockton Arkose with a predominance of Na-feldspar, confirming derivation of most of the Newark basin fill from an eastern or southeastern source. This thick (6 km) sequence is the record of interior basin sedimentation in a major rift valley developed during the early stage of post-Appalachian-Variscan opening of the central Atlantic Basin. The return trip to Newark crosses the Brunswick mudflat lowland in the middle fault block (Fig. 3, 4), then continues northeastward along the south flank of the Watchung lava flows.
The focus of the field trip is on the principal sedimentary facies and the successive changes in sedimentation displayed in the Newark Basin. In this review particular significance is attributed 1) to the eastern upland as the source of the distinctive soda-rich basin fill, 2) to relatively intense weathering in the upland terrane required to produce the large supply of clay in the Lockatong and Brunswick formations, in contrast to the evidence of aridity in the basin reflected in many of the sedimentary features, 3) to a long interval of stability during development of the graben documented by the Lockatong lacustrine deposits, and 4) to several patterns of allocyclic sedimentation recorded in the Lockatong and Brunswick deposits.

14: LATE TRIASSIC PART OF NEWARK
SUPERGROUP, DELAWARE RIVER SECTION

Many zones of reversed magnetic polarity
Interbedded Brunswick (Passaic) reddish-brown arkosic sandstone and mudstone with thin layers of dark gray micaceous mudstone. Local exposures of fining-upward fluvial sequences. See Olsen, this guidebook for revised stratigraphic nomenclature.
Samples across this traverse to the border fault reveal that the 1250m section of Late Triassic Brunswick beds below the 1st Watchung lava flow contains many zones of reversed magnetic polarity. All of the Liassic strata (1750m) above the 1st flow are normally magnetized (McIntosh and Hargraves, 1980, ms; Cornet and Traverse, 1975).

1st Watchung lava flow (Orange Mountain Basalt)
1st Watchung lava flow (Orange Mountain Basalt) 50-65m thick. Basal contact covered. Very thin hornfels facies with small patches of copper minerals. Lower part displays well-developed colonnade with vertical columnar joints. Main body of flow is curvi-columnar zone with closely-spaced radiating joints. (See Manspeizer, this guidebook). Roadcut is 38m deep, said to be the deepest east of the Mississippi River.

Brunswick (Feltville) Fm
Crossing Pleasant Valley Way in mudflat and lacustrine facies of Brunswick (Feltville) Formation between 1st and 2nd Watchung Mts.

2nd Watchung flow (Preakness Mountain Basalt).

Towaco Formation
Crossing lowland in reddish-brown fluvial and dark gray lacustrine Towaco Formation (37m). Rikers Hill (Roseland) National Monument (dinosaur tracks) to SW. Locally some of these lacustrine deposits contain traces of hydrocarbons.

3rd Watchung lava flow (Hook Mountain Basalt)
Crossing 3rd Watchung lava flow (Hook Mountain Basalt). Each Watchung flow was extruded somewhat later than renewed faulting and differential uplift of the flanking highlands that produced fanglomerates (Faust, 1978).

Passaic River
Passaic River, drains Hatfield Swamp on broad expanse of uppermost Brunswick (Boonton) Formation to W.

3rd Watchung flow
North horn of New Vernon anticline in 3rd Watchung flow to S.

Patch of Hammer Creek Conglomerate in low hill to SE.

Ramapo border fault
Narrow gap between Ramapo border fault and west end of New Vernon anticline in 3rd Watchung flow. The fault continues for about 50 miles to the NE end of the basin (see Ratcliffe, this guidebook).

Crossing Passaic River.
In its last stage Glacial Lake Passaic drained northeastward through gaps in the Watchung flows at Little Falls and Paterson. Great Swamp National Wildlife Refuge to S is a swampy remnant in broad syncline above the 3rd Watchung flow.

Narrow gap between 2nd and 3rd Watchung ridges.

Moggy Hollow
Moggy Hollow (Mine Brook Road) between recurved 2nd Watchung Mt. to NW and 3rd Watchung (Long Hill) Mt. to ESE. Early drainage of Glacial Lake Passaic flowed westward through this notch to the North Branch of the Raritan River. West scarp of 2nd Watchung faulted against Brunswick Formation (Adams, 1980).

Watchung Mts. on skyline to E.

Syncline in New Germantown flow in low hills a mile N.

NE end of Flemington Fault
Crossing NE end of Flemington Fault at junction with the border fault (near Lebanon). To S Cushetunk Mt. (diabase) encloses Round Valley Reservoir.

Cambro-Ordovician strata and Precambrian gneiss
Complexly faulted Cambro-Ordovician strata and Precambrian gneiss that project S into the Newark Basin are limited on E by the Flemington Fault.

Remnant of a Taconic klippe
Reddish-brown and gray Early and Middle Ordovician shale with thin beds of chert and limestone. Apparently a remnant of a Taconic klippe (Perrisoratis, 1974).

Ordovician shale overlapped by Hammer Creek Conglomerate.

On northern edge of Hammer Creek Conglomerate
On northern edge of Hammer Creek Conglomerate covering Cambro-Ordovician strata faulted against Precambrian gneiss.

Cross Rt. 579 on border fault.
Large fan of quartzite-rich conglomerate interfingers with Brunswick, Lockatong, and Stockton formations to E and SE. Evidence that movement on border fault occurred throughout episode of basin-filling.

Brunswick Formation
Brunswick Formation S of narrow belt of limestone-pebble conglomerate.

Brunswick Mudstone between fanglomerates.

Continue W on Church Road along border fault.

Quarry in Hammer Creek Conglomerate
Quarry in Hammer Creek (Silurian quartzite clasts) Conglomerate to S. Clasts shattered by crushing in fault zone. Detailed map of Musconetcong Mt. to N and Newark Supergroup S to Frenchtown by Drake and others, 1961, 1967.
2011: Workings apparent in GE photos before 1997. --OHM

Cambrian limestone and border conglomerate
Traverse crosses narrow belt of Cambrian limestone and border conglomerate, and the Brunswick Mudstone between lobes of Hammer Creek Conglomerate. Good exposures of border fault relations across the Delaware River at Monroe (0.5 mi S of Durham Furnace on PA 611).

Cliff on far side of river
Cliff on far side of river above power station shows patterned sequence of middle Brunswick deposits seen at Stop 2. Plateau capped by Coffman Hill diabase sheet (165 m) above gray Brunswick hornfels. The sill is estimated to be about 1400m below the 1st Watchung lava flow.

STOP 1. Hammer Creek Conglomerate
STOP 1 Hammer Creek Conglomerate, Pebble Bluffs at culvert.

Stop 1B. Conglomerate in steep roadcut
Southward projecting lobe of quartzite-rich fanglomerate dipping 10-15 NW. Most clasts are less than 8 cm in diameter, a few are 13 cm long, the largest are 25 cm long. Some clasts are imbricated. Bedding is very poorly developed; cross-bedding is virtually absent.
The poorly sorted detritus is arranged in crudely fining-upward sequences about 7-9 m thick (Fig. 5) with a scoured base, multi-storied units of conglomerate, and calcareous patches and nodules (calcrete paleosol) in the upper sandier part.
Significant items:
1. Outcrop less than 5 mi from border fault.
2. Source probably less than 25-30 mi to N.
3. Clasts and matrix derived from Paleozoic rocks now stripped from the uplands.
4. Fining-upward sequence and calcrete common in alluvial fans.
5. Lensing and channeling well-displayed at south end of bluffs.
6. Rapid gradation southward into distal, finer-grained facies.
7. Fault in ravine between two major outcrops.

STOP 2. Middle Brunswick Mudstone
Long roadcut in essentially horizontal middle Brunswick Mudstone south of Spring Valley Road. Bright reddish-brown mudstone in patterned sequences about 950 m above base of formation (Picard and High. 1963).
Items along 0.2 mi traverse:
1. Normal fault at E end of exposure down to E. Conspicuous jointing.
2. Succession of about 30 massive mudstone and hackly claystone alternations averaging 1.5-3 m thick (Picard and High, 1963). Few units with persistent 1-2 cm beds of siltstone.
3. Abundant burrowing has destroyed lamination in mudstone. Absence of bedding in claystone may be result of small-scale physical disruption.
4. Distinct 2-6 cm layers filling abandoned channel (Fig. 6). Fine-to-medium grained feldspathic sandstone in lower part of each layer derived from southeastern Na-feldspar-rich source area. Some layers are graded. Tops are marked by burrows and shrinkage cracks. Abandoned channel may have been part of inter fluvial drainage of extensive alluvial plain (Allen and Williams, 1979) or a shallow waterway in a clay-flat playa.
5. Hammer Creek tongue of dark reddish-brown Paleozoic quartzite-clast lithic-rich sandstone 3 m above 11.1 road E and W of ravine and culvert.

Perkasie and Land M members of Brunswick
Fm
Dark gray Perkasie and Land M members of Brunswick
Formation 930 m above Lockatong Formation. These are highest of 8 recurring gray units in the Delaware Valley region, centered at 120-137 m intervals (Fig. 1). Several have been traced to NE into Hammer Creek Conglomerate (Fig. 4), as well as 25 km to SW where they interfinger with reddish-brown mudstone. Gray units consist of black, pyritic platy muddy limestone and calcareous mudstone. The Perkasie Member apparently is about 1400 m below the 1st Watchung flow. Intervals of reversed magnetic polarization have been identified below both the Perkasie and L and M units, as well as just below and above the Graters Member lower in the formation (W.C. McIntosh and R.B. Hargraves, 1980, Ms).

STOP 3. Middle Brunswick Mudstone
Middle Brunswick Mudstone, roadside excavation. Well-displayed bedding surface markings, including several sizes of shrinkage crack-patterns, burrows, and small tracks and trails, many probably made by small crustaceans (Boyer, 1979).

Gray units E through H
Gray units E and F exposed in ravine and along side road. Gray units G and H above 100 m higher in section constitute the Graters Member (40 m thick).

Gray unit D exposed in ravine of Warford Creek.

STOP 4. Lowermost Brunswick Fm, Tumble Falls.
Ravine and high roadcut in lowest reddish-brown unit and lowest gray unit C (40 m thick) about 75 m above base of formation (Fig. 1, 7). Reddish-brown mudstone units exhibit three distinctive disruption features:
1. Thin greenish-gray beds with scattered shrinkage wafers.
2. Layers of light brown-weathering dolomitic mudstone 1-3 cm thick, in both pull-apart structures and widely dispersed fragments.
3. Upward-concave surfaces of shearing in tent-like structures 15 to 30 cm high suggestive of gilgai formed in soils by repeated wetting and drying.
The uppermost platy part of gray unit C consists of:
1. Black pyritic mudstone layers 2-3 cm thick with wide, completely crumpled composite and injected shrinkage crack casts of brown-weathering muddy dolomite and minor calcite.
2. Lenses of pyritic peloidal dolomite 10-20 cm thick, with silty round and flattened burrow casts and thin arcuate calcitic skeletal debris (ostracodes?) in the upper part. Many of the peloids are crudely concretionary dolomite with internal shrinkage cracks filled with sparry calcite. They may be algal oncolites.
The overlying massive reddish-brown mudstone contains tiny flecks of pyrite and irregular tan calcareous nodules 1-5 cm long that may be algal structures. Many of them have irregular patches of sparry calcite or are crudely concretionary.

Double Red unit exposed in creek to E
Double Red unit exposed in creek to E is uppermost reddish-brown sequence of analcime-rich chemical cycles assigned to the Lockatong Formation. Thin reddish-brown intervals of this sort are the most analcime-rich and recur in a 105-120 m pattern of long cycles in phase with thick reddish-brown units in the Brunswick Formation

Triple Red unit in abandoned building-stone quarry
Triple Red unit in abandoned building-stone quarry to E about 1000 m above base of Lockatong Formation. Red units were favored for building blocks because of their more interesting variegated colors.

STOP 5A. First Big Red unit, Lockatong Fm
First Big Red unit about 35 m thick, Lockatong Formation, roadside outcrop, north end of Byram road cut. Short chemical cycles consist Of lower platy dark lavender analcime-rich argillite with intraformational breccia and conspicuous shrinkage cracks with large white patches of analcime and dolomite. Upper massive part is reddish-brown, and spotted with tiny specks of analcime and dolomite locally arranged in rosettes of radiating skeletal crystal casts.
Profile of ledges in long Byram roadcut to S (395-730 m above base of Lockatong Formation) outlines succession of short cycles (Fig, 2B).

STOP 5B. Short detrital cycles of Lockatong Fm.
Short detrital cycles in gray sequence of Lockatong Formation. Easily eroded black shale in lowest part and feldspathic (Na-feldspar predominates) siltstone and fine-grained sandstone in the upper part (Fig. 2A). Essentially a very fine-grained distal facies of Stockton Arkose.

First thin Red unit in Lockatong Formation.
Lowest of the several red units in the Newark section (Fig. 1).

STOP 6A. Short chemical cycles of Lockatong Fm
Short chemical cycles in gray unit of Lockatong Formation between 450-550 ft marks (Fig. 8). Gray analcime-rich chemical cycles 2-4 m thick (Fig. 2) are characterized by:
1. Platy lower part of alternating black mudstone and tan-weathering dolomitic layers disrupted by shrinkage cracks and pull-aparts.
2. More massive middle part with extensively disrupted dolomitic layers.
3. Upper more homogeneous analcime-rich part, commonly speckled with tiny patches of analcime and dolomite distributed in a pattern of minute shrinkage cracks. Locally analcime and dolomite occur in sprays of skeletal crystal casts.

Lockatong cancrinite-rich hornfels
Large abandoned quarry in Lockatong cancrinite-rich hornfels (chemical cycles; Fig. 8). Cancrinite is present 130 m (425 ft) stratigraphically above the faulted contact with the Byram diabase to the S. Two well-defined detrital cycles at top of quarry wall.

STOP 6B. Lockatong hornfels and Byram diabase sill
Lockatong hornfels and Byram diabase sill, to south end of roadcut (Fig. 8).
1. White sprays of cancrinite, albite, and calcite at 21 ft mark developed from analcime-dolomite crystals in a chemical cycle, as seen in First Big Red units (Stop 5a).
2. Nepheline developed in hornfels 25 m (11 ft mark) above Byram Sill. .
3. Metal disk 2 m above road at 10ft mark records flood level in Sept. 1955.
4. Faulted upper contact with diabase sill (Fig. 8) and essentially undisturbed contact with xenolith. Lockatong chemical cycles metamorphosed to nepheline cancrinite, calcite, pyroxene and amphibole, biotite-albite hornfels (an aphanitic syenite!).
5. Extensively fractured coarse-grained diabase with abundant joint minerals including calcite, epidote, prehnite, tourmaline, and amphibole. Conspicuous horizontal lineations marked by concentrations of joint minerals are not related to compositional layering in the sill.
6. Vague cyclic pattern of ledges of albite-biotite hornfels S of sill. Nepheline occurs about 30 m (100 ft) below the sill.

Southernmost roadside outcrop of Lockatong hornfels
Southernmost roadside outcrop of Lockatong hornfels, about 80 m below Byram sill.

Crossing estimated Lockatong-Stockton contact.

Uppermost Stockton Formation
Well-bedded reddish-brown sandy mudstone and sandstone in uppermost Stockton Formation.

Raven Rock.
Upper arkosic member 100 m thick (Fig. 1).

Lockatong Creek.
Quarry in Cutalossa Member of Stockton Formation (Fig. 1) high on west bank of river.

STOP 7. Middle Stockton Arkose
Quarry 1 mile N of Stockton. Upper Prallsville Member (Fig. 1) 61 m thick, 760 m above base.
1. Yellowish-gray, well-sorted, medium-grained arkose with only minor reddish-brown micaceous mudstone.
2. Horizontal bedding predominates; with local micro-placers of specular hematite (after magnetite) on bedding planes.
3. Large-and small-scale cross-bedding rare.
4. Intraformational mud-chip conglomerate common.
5. Isolated burrows in arkose and on bedding planes. Micaceous mudstone extensively burrowed.
6. Small yellowish-brown patches common in arkose are limonite after altered iron-rich carbonate cement.
7. Na.feldspar almost twice as abundant as K-feldspar.
8. Very coarse-grained, kaolinized arkose along upper rim of Quarry with clasts of quartz, feldspar, quartzite, and gneiss.

Conglomeratic Solebury Member
Conglomeratic Solebury Member (115 m thick) of Stockton Formation in schoolyard to E.

Arkosic conglomerate of Solebury Member
Roadcut in arkosic conglomerate of Solebury Member. Clasts as large as 8 cm mostly quartzite, rare feldspar and gneiss.

Crossing Flemington Fault at Brookville
Crossing Flemington Fault at Brookville (Fig. 4). To W in Pennsylvania uplifted Cambro-Ordovician limestone is overlain by conglomeratic limestone-clast facies of Stockton Formation.

Lockatong nepheline-cancrinite hornfels
Lockatong nepheline-cancrinite hornfels above Mt. Gilboa diabase. Nepheline and analcime syenites at top of sill probably formed by reaction of a xenolith of Lockatong chemical cycles with a granophyric differentiate of the coarse-grained diabase (Barker and Long, 1969).

Mt. Gilboa trap-rock quarry
Mt. Gilboa trap-rock quarry in unusually coarse-grained diabase (gabbro). Lockatong hornfels along south edge of quarry.

Dilts Corner Fault
Crossing southern branch of Flemington Fault (Dilts Corner Fault).

Brunswick Formation
Join US 202 to NE across Brunswick Formation north of Lambertville sill.

15A: BRITTLE FAULTS (RAMAPO FAULT) AND
PHYLLONITIC DUCTILE SHEAR ZONES (Saturday)
NICHOLAS M. RATCLIFFE
U.S. Geological Survey
Reston, Virginia 22190
Introduction and rationale for investigations
Field investigations at the northern end of the Newark basin begun more than 10 years ago led to the publication of several articles (Ratcliffe, 1971; Ratcliffe and others, 1972) in which a case was made for long continued fault activity in the vicinity of the border (Ramapo fault) in New York and New Jersey.
These articles also called attention to the observation that a series of low-level earthquakes appears to be spatially associated with these ancient faults (Fig. 1).
Since that time, seismic-detention capabilities of the Lamont-Doherty network have been greatly improved and further supplemented by a dense array of stations located on the northern extension of the Ramapo fault in the vicinity of Consolidated Edison's nuclear generating plants at Indian Point (Fig. 2).
Aggarwal and Sykes (1978) document a pattern of seismicity (Figs. 1 and 2) that illustrates that numerous low-level events (Nuttli magnitude 1.5 to approximately 3) are occurring throughout a 30 km-wide zone roughly centered on the trace of the Ramapo fault at depths of 0 to about 10 km. Fault-plane solutions (Fig. 2) obtained by them and by Yang and Aggarwal suggest that motion is currently taking place on northeast-striking
southeast-dipping surfaces. First-motion studies indicate southeast-to-northwest compression and therefore a reverse-faulting mechanism. They conclude that current seismicity in the Ramapo zone is being controlled by reactivation of the northeast-striking steeply southeast-dipping faults which make up the predominant structural grain in this area. They further suggest that the Mesozoic border fault, the Ramapo fault, and its northern splays (Fig.1) are the actual surfaces being reactivated.
The geologic framework of the Ramapo seismic zone, however, is extremely complex. A multitude of faults of different ages have different physical characteristics and contrasting histories. The northeast-trending structural grain of this zone is accompanied by faults of Proterozoic, Paleozoic, Mesozoic and possibly Tertiary and recent age.
Despite the abundant evidence for reactivation of older faults in the Mesozoic, (Ratcliffe, 1971) the Mesozoic and younger faults are not uniformly distributed and do not everywhere coincide with the traces of older faults. Unfortunately, it is not presently possible to produce a tectonic map of this area that accurately shows the distribution of Mesozoic as opposed to older faults. In general, previous studies have not attempted to differentiate Mesozoic faults except where Mesozoic rocks are actually offset. The geologic-tectonic template, therefore, is quite incomplete at present, and any plan to test the hypothesis that geologic structures of Mesozoic age are responsible for current seismicity is severely limited by the lack of appropriate geologic data. Figure 1 shows a new preliminary compilation of fault features

15A: BRITTLE FAULTS (RAMAPO FAULT) AND
PHYLLONITIC DUCTILE SHEAR ZONES (Saturday)

Excellent crops of "First Watchung" basalt
Excellent crops of "First Watchung" basalt (Orange Mountain basalt in Olsen this guidebook) Minor faults strike N. 20° E. and dip 80° SE. and have broad shear zones with gouge and subhorizontal slickensides.

Crops of platy jointed basalts of Second Mountain
Crops of platy jointed basalts of Second Mountain (Preakness Mountain basalt of Olsen, this guidebook)

View in distance of Hudson Highlands and Ramapo fault escarpment.

Conglomerate at Montville of Carlston
Excellent crops of the conglomerate at Montville of Carlston (1946) here contain cobbles of hornblende granite, gneiss, epidote veined cataclastic gneiss, "Franklin Marble", and abundant clasts of basalt. These deposits are the youngest rocks in the Newark basin.

Turn left on Old Lane and crops of gneiss boulder conglomerate.

STOP 1. Mulbrook Lane.
Stop at end of circle -Sliver of Cambrian quarzite phyllonite and Ramapo fault breccia
At east side of circle is brown, very shattered, dioritic gneiss(?). To west up slopes by house are crops of vitreous quartzite of probable Cambrian age. Farther west, across small swale, are excellent crops of pale-green, phyllonite gneiss typical of the more ductile deformation zones in the Hudson Highlands.
Sericite, epidote, and needles of actinolite are found in the phyllonite which exhibits strong right-lateral strain slip folds. Ductile deformation is characteristic of these zones along the western edge of the Mesozoic basin.
This quartzite forms one of a series of similar slivers of Cambrian and Ordovician cover rocks that are found west of the Ramapo fault from Boonton north to Tomkins Cove and are interpreted as fault slivers within the ductile shear zones of pre-Mesozoic age. The phyllonite zone forms a continuous belt along the Ramapo to Riverdale where the shear zone may bifurcate with part of the zone extending northward into the Proterozoic rocks along the Lake Inez shear zone.
The cataclastic rocks east of the circle are more typical of cataclastic rocks associated with Mesozoic faulting on the Ramapo.

Low crops of what may be the 4th Watchung lava flow
Turn right on Indian Lane -low crops of what may be the 4th Watchung lava flow; excellent crops in gas pipeline.

STOP 1b. Optional stop. Roadcuts at entrance to golf course at Jacksonville.
Grey to greenish-grey coarse conglomerate (Jc) that contains fragments of "Franklin Marble," detrital graphite, coarse cobbles fragments of hornblende granite gneiss and epidote-veined phyllonite from the older phyllonite west of the Ramapo fault. To the south, a lava flow younger than the "Third Watchung" lava flow overlies fanglomerate. A waterwell drilled in 1979 penetrated 50 feet of basalt and bottomed at 130 feet in grey and red shale conglomerate near this site.
These sedimentary rocks and the lava flows are the youngest rocks known in the Newark basin, based on the palynology of Cornet (1977) who identified these rocks as Sinemurian (middle Early Jurassic).
The nonfolded outcrop pattern of these Sinemurian deposits as compared with the marked northwest-trending folds affecting the Watchung lava flows is notable. This suggests to me that the northwest crossfolds may have formed prior to cessation of fanglomerate deposition.

Stop 2. Large sandpit southwest of traffic circle
2011: Traffic Circle is gone, sand pit is gone, now we have Interstate 287, which in 1980 terminated somewhat south of here. As much of the discussion is about drill cores, it is all copied here. OHM
Just after traffic circle pull over to right. Stop 2 -cross over highway with caution to large sandpit. Bus will turn around and meet us on east bound side of Route 23.
Stop 2. Large sandpit southwest of traffic circle at Riverdale. (See Fig. 5,6,7).
Discussion of core drilling at Riverdale site and bedrock exposures of phyllonitic shear zones and epidote veined cross faults.
Excellent pavement exposures of phyllonitic hornblende granite gneiss and quartzite paragneiss can be seen. Isoclinal folds with axial planes of N. 35° E., 72° E. are crossed by cross faults locally marked by epidote veins cross-faults N. 65° E., 72° SE., N. 30° W., 90°, N. 25° W., 85° NE. show predominant left-lateral and reverse movement.
At the south end of pit, a mylonitic grey, quartzose gneiss is crossed by small crenulations and down-to-east faults. Along the entire border fault, phyllonite where present near the Ramapo is crenulated and micro-faulted with veins of calcite and laumontite. This is typical of Mesozoic mineralization. The phyllonite predates the epidote-rich crossfaults that are of unknown age.
In the sand pits to the south, two continuous core drill holes penetrated the Ramapo fault, see figures 6 and 7. The fault offsets fanglomerate of probable Sinemurian Age of the hanging wall against phyllonitic gneiss of the ductile shear zone.
The actual fault is expressed by 1 cm of soft gouge, consisting of pulverized rock material. Below the fault, green phyllonite, like that seen in the exposures here, is crenulated and displaced on normal faults. Excellent recovery of the fault zone material has permitted thin section examination of the actual fault. The sawtooth contact is preserved showing down-to-the-southeast sense of movement with no evidence for reactivation since this last normal movement. Chlorite-coated surfaces, microbreccia and cataclasite, and "mylonitic" cataclasite with a pronounced fluxion structure are common in the cores. The actual fault is remarkably sharp and well defined in each core. The fault dips 50° SE. assuming a N. 40° E. strike as indicated from outcrop data to the south.
Sections of the actual core will be available for inspection. PLEASE DO NOT REMOVE CORE FROM BOXES.

STOP 3. Lake Inez shear zone exposures in abandoned sandpit.
2011: Sand pit is evident on GE images from 1995. OHM
Pavement exposures of phyllonitic. amphibolite gneiss and pink pegmatite show right-lateral displacement of pegmatite on N. 15° E., 30° SE. dipping shear zones. Chlorite, epidote and sericite mark phyllonite zones. Later cross faults N.65° W., 60° SW. show left-lateral displacement of shear zones and are marked by veinlets of epidote. This is the northerly extension of the same shear zone seen at Stop 2.
Up the hillside to the east, exposure of gneiss show reactivation of gneissic layering. Within this area, all suitably oriented surfaces, gneissic layering, mylonite zones and more brittle thrust faults all show evidence of reactivation in the Mesozoic movement sense. Widespread reactivation in this area follows the steep northeast-trending structural grain developed in "Grenville" and Taconic tectonism.

Abundant brittle faults as well as more ductile ones
Turn right on Skyline Drive -excellent crops in Erskine area show abundant brittle faults as well as more ductile ones. Reactivation has been widespread.

Epidote-filled cross fractures
Near crest of hill at gas pipeline epidote-filled cross fractures with excellent wear grooves suggest Mesozoic reactivation.

Exposures of faulted basalt

Stop 4. (Optional stop) "Coal Mine"
Reports from a desultory mining operation in the late 1800's refer to small coal prospect on the west bank of the Ramapo River 1/4 mile north of Crystal Lake.
This exposure is a sliver of coal black graphitic phyllite ("Annsville Phyllite") similar to the exposure along the border fault at Riverdale. Sketch map figure 9 shows the relations. The sliver of black phyllite is found between two outcrops of gneiss. Very mylonitic gneiss is located to the west. Gneiss exposed east of the sliver has a composite fabric with brittle fractures and abundant microbreccia. The relationships seen here are similar to those seen at Stop 1 and those to be seen at Stop 9 on the Thiells fault. The brittle fractures are spatially related to Mesozoic faulting: the more ductile shears are associated with thrust and strike~slip faulting of probable Ordovician age and represent the southwestward extension of the Canopus zone fault exposed north of the Newark basin. Drill holes for water wells about 400 feet north of this site penetrated granite gneiss in holes 500 feet east of this locality. The "Annsville Phyllite" inclusion does not occur within the Mesozoic border fault but lies west of it as part of the footwall block.

Stop 5. Optional Stop. Cataclasite and fault fabric
Cataclasite and fault fabric in cataclastic gneiss at Ramapo fauit, Suffern.
These small exposures of black, chlorite-coated, cataclastic, hornblende-granite gneiss are much more instructive than the exposures north of Suffern commonly visited by field trips. Excellent chlorite-slick surfaces dip in conjugate fashion northwest and southeast and exhibit down-to-the-south right-oblique slip on southeast-dipping surfaces and down-to-the-west and left-oblique movement on southwest-dipping surfaces. The near-vertical attitude of the extension fractures here and in the Sky Meadow drill core suggests that the rocks of the footwall block have not undergone rotation after formation of the cataclastic fabric.

STOP 6. Union Hill trap quarry
Union Hill trap quarry and contact of lava flows with fanglomerate.
We are permitted entrance with the clear understanding that we will not attempt to enter the quarry proper. Please respect the owners' wishes. Use extreme caution near steep cliffs on west side of exposure.
Superb exposures at the south end of the quarry near the rock crushers show a vertical wall of coarse fanglomerate, enclosing a large boulder of brecciated dolostone in an apparent channel that, in turn, is overlain by an upward-fining cycle ending in fine red shale with greenish slate chips. Vesicular pillow lava directly overlies this shale.
Clasts in the fanglomerate include epidote-rich hornblende granite gneiss, Silurian Green Pond conglomerate, dolostone clasts, and several cobbles of basalt pillows. I interpret the large boulder as a block of breccia from the border fault, and the clasts of pillow basalt as blocks eroded from the southward-advancing Ladentown lava flows.
In the Ladentown-Suffern area, alluvial deposits such as those seen here contain boulders of felsic dikes uniquely traceable to the Rosetown dike swarm. These data indicate, as do the observations at the next stop, that a southerly-directed Jurassic drainage system was present near the border fault prior to eruption of the flows at Ladentown and Mount Union. Perhaps the debris flow material seen here are earthquake-activated deposits formed immediately prior to extrusion of the Ladentown basalt. The basalts seen here are correlated with basalts of the "First Watchung" on the opposite limb of the Suffern cross anticline.
2011 Older GE imagery shows the quarry in its prime, particularly before 2004. OHM

Sky Meadow Road -drill site is at base of mountain to left.

Stop 7. Basalt at Ladentown
Basalt at Ladentown and discussion of drill data from the Ramapo fault.
Note exposures and attitude of red quartz-pebble arkose by road and walk north to ridge behind house. Multiple basaltic lava flows with pahoehoe tongues and snouts as well as small pressure ridges may be seen. BE VERY CAREFUL NOT TO DISLODGE BLOCKS THAT WOULD TUMBLE INTO THE BACKYARDS OF THE HOUSES BELOW. Flow direction obtained from similar exposures suggest that the lava flows were flowing southwest toward the border fault and that the base of the lavas flows are at lower elevations to the southwest.
Drill-core data from Sky Meadow Road suggest that vesicular lava and multiple flows of lava more than 450 ft. thick accumulated near the border fault. These speculations would require a local relief in the basin adjacent to the border fault of approximately 450 ft.
Results of the drilling of the border fault will be discussed (see text).
2011: Very good GE image: 4/29/2004 OHM

Fanglomerate found immediately below Ladentown lava flows just past intersection.

Stop 8. Excellent exposures of Mesozoic fault features
(Optional stop). Excellent exposures of Mesozoic fault features on Cheesecoate Mountain north of Newark basin and view of Newark basin.
This block of Proterozoic gneiss lies east of the Ramapo fault but west of the Thiells fault. It may represent a horst of basement rock that was structurally high during Triassic sedimentation. The principal argument in favor of this contention is the dominance of northeast-striking faults that appear to pass into the basin but do not disrupt the continuous belt of intrusive and extrusive lava.

Traversing possible horst block
We are traversing a belt of gneiss that possibly forms a horst block between the Ramapo fault and the Thiells fault.

STOP 9. Thiells fault.
This small but significant exposure (Fig. 12) illustrates well the difference between Mesozoic faults as seen in drill record and the older mylonitic faults of probable Ordovician age. The Thiells fault is an oblique-thrust fault that juxtaposes the Manhattan Prong rocks against those of the Reading Prong. Abundant ultramylonite, pseudotachylite, and mylonite with metamorphic mineralization affects Proterozoic Y and Paleozoic rocks everywhere along the fault. Figure 12 shows the structural relaltionship exposed in the small quarry behind the houses.
K-Ar data on sericite that replaces mylonitic quartzite yields an age of 379± 13 m.y. (386 m.y. using newer constants). K-Ar data on pseudotachylite from a locality to the north gave an age of 259 ±9 m.y. (264 m.y.). The mylonitization and sericitization associated with the fault are totally unlike that found on any proven Mesozoic fault.
Fracturing in the quartzite at the east side of the exposure may be related to Mesozoic faulting. The similarity of this exposure to that seen at Stop 1 is striking.

STOP 10. Triassic quartzite-rich fanglomerate and cataclastic
Annsville at Cedar Pond Brook, Stony Point. (See fig. 14 for location).
Exposures of black cataclastic "Annsville Phyllite" may be seen at the banks of the small pond west of the dam. Thin-section examination of the east-dipping fabric reveals up-from-the-southeast microdisplacements and abundant clinozoisite and sericite replacement veinlets. This fabric is associated with the Thiells fault that crops out to the west.
A light-colored conglomerate of uncertain origin overlies phyllite and contains fragments of brecciated "Wappinger Limestone" and "Annsville Phyllite". This conglomerate may be a basal triassic conglomerate deposited unconformably on the cataclastic "Annsville Phyllite'. Light-grey carbonate-rich conglomerates similar to this are found along the unconformity at Tomkins Cove to the north.
Large crops of coarse fanglomerate are seen at the dam to the northeast. Quartzite clasts dominate. Cambrian Poughquag Quartzite crops out 1,000 ft to the west where it forms an unconformable cover on the gneiss of the Hudson Highlands west of the Thiells fault. This suggests very local source area for the fanglomerate and further suggests that little post-depositional separation has occurred in this area.
Drill data from cores and trenches 800 ft to the north are shown in figures 13 and 11. A normal fault dipping 70° SE. was intercepted in two vertical drill holes. Cataclasite and gouge typical of other Mesozoic faults marked the fault zone. Unexpectedly, gneiss forms the footwall in Cem. 1. A possible interpretation of the data is shown in figure 13. It is notable that none of the distinctive ultramylonitic rocks seen at the Thiells fault (Stop 9) were found at the border fault. This illustrates the difference between Mesozoic brittle fault products and ductile fabrics of Ordovician faults.

STOP 11. Fanglomerate at Stony Point
Fanglomerate at Stony Point at northern end of Newark Basin.
Limestone fanglomerate unconformably overlies Inwood Marble and "Annsville Phyllite" along the east-west Triassic outcrop belt at Tomkins Cove. Exposures in the railroad cut along the slopes contain inclusions of dolostone traceable to the immediately adjacent dolostone in the Tomkins Cove quarry. Small chips of distinctive biotite-rich hornfelsed Manhattan Schist typical of the contact facies bordering the Cortlandt Complex have been found in the fanglomerate at this locality. Very local sediment sources are suggested by these data.

15B: BRITTLE FAULTS (RAMAPO FAULT) AND
PHYLLONITIC DUCTILE SHEAR ZONES (Sunday)
NICHOLAS M. RATCLIFFE
U.S. Geological Survey
Reston, Virginia 22190
Introduction and rationale for investigations
Field investigations at the northern end of the Newark basin begun more than 10 years ago led to the publication of several articles (Ratcliffe, 1971; Ratcliffe and others, 1972) in which a case was made for long continued fault activity in the vicinity of the border (Ramapo fault) in New York and New Jersey.
These articles also called attention to the observation that a series of low-level earthquakes appears to be spatially associated with these ancient faults (Fig. 1).
Since that time, seismic-detention capabilities of the Lamont-Doherty network have been greatly improved and further supplemented by a dense array of stations located on the northern extension of the Ramapo fault in the vicinity of Consolidated Edison's nuclear generating plants at Indian Point (Fig. 2).
Aggarwal and Sykes (1978) document a pattern of seismicity (Figs. 1 and 2) that illustrates that numerous low-level events (Nuttli magnitude 1.5 to approximately 3) are occurring throughout a 30 km-wide zone roughly centered on the trace of the Ramapo fault at depths of 0 to about 10 km. Fault-plane solutions (Fig. 2) obtained by them and by Yang and Aggarwal suggest that motion is currently taking place on northeast-striking
southeast-dipping surfaces. First-motion studies indicate southeast-to-northwest compression and therefore a reverse-faulting mechanism. They conclude that current seismicity in the Ramapo zone is being controlled by reactivation of the northeast-striking steeply southeast-dipping faults which make up the predominant structural grain in this area. They further suggest that the Mesozoic border fault, the Ramapo fault, and its northern splays (Fig.1) are the actual surfaces being reactivated.
The geologic framework of the Ramapo seismic zone, however, is extremely complex. A multitude of faults of different ages have different physical characteristics and contrasting histories. The northeast-trending structural grain of this zone is accompanied by faults of Proterozoic, Paleozoic, Mesozoic and possibly Tertiary and recent age.
Despite the abundant evidence for reactivation of older faults in the Mesozoic, (Ratcliffe, 1971) the Mesozoic and younger faults are not uniformly distributed and do not everywhere coincide with the traces of older faults. Unfortunately, it is not presently possible to produce a tectonic map of this area that accurately shows the distribution of Mesozoic as opposed to older faults. In general, previous studies have not attempted to differentiate Mesozoic faults except where Mesozoic rocks are actually offset. The geologic-tectonic template, therefore, is quite incomplete at present, and any plan to test the hypothesis that geologic structures of Mesozoic age are responsible for current seismicity is severely limited by the lack of appropriate geologic data. Figure 1 shows a new preliminary compilation of fault features

15B: BRITTLE FAULTS (RAMAPO FAULT) AND
PHYLLONITIC DUCTILE SHEAR ZONES (Sunday)

STOP 12. Tomkins Cove quarry in "Wappinger Limestone"
Tomkins Cove quarry in "Wappinger Limestone" (Inwood Marble) and fault exposures north of the Newark basin.
This large quarry in "Wappinger Limestone" (Fig. 14) forms the axial portion of a westward overturned anticline bordered by "Annsville Phyllite" on the west and Manhattan Schist unit A on the east.
Well-layered beige-to-tan weathering quartzose dolostone with phyllite partings forms the central part of the quarry and is bordered on the west by southeast-dipping overturned but highly folded light gray nonquartzose dolostone and black phyllite.
Plane table mapping of the quarry at 1" = 200 with structural geology students at City College has shown that straight forward correlations of units across the quarry is not possible because of eight major fault zones that disrupt the structural continuity. These faults are expressed by red or green zones of clay gouge and phyllonite. Several of these features can be seen on the south face of the quarry exposed in all three levels.
Structural analyses of the fabric associated with these faults indicate that most are southeast-dipping reverse faults with left-lateral or right-lateral components of movement. Minor folds within shear zones plunge steeply down the dip of fault surfaces, commonly normal to slickensides. Faults are located on the limbs or isoclinal overturned folds exhibiting excellent metamorphic fabric and ductile fold styles.
Despite the young looking nature of these faults they appear to be compressional features formed during Taconic dynamothermal metamorphism. Reactivation may have produced the clay gouge and slickensides locally.
Within the quarry, at the extreme west in corner of level 2 and near the southeastern corner of level 3, N.S. steep north-trending faults offset the older clay gouge zones and produce drag folding of older slickensided surfaces.
The western fault is coated with fibrous palygorskite that forms an excellent slickenside lineation. K-Ar dating of this mineral by H. Kruger yielded an age of 183 ± 31 m. y. These data suggest that the prominent clay gouge seams seen in the quarry are older than 183 ± 31 m.y. The palygorskite-coated fault probably is Mesozoic. The fact that the red clay gouge thrust fault zones are not recognized in the Triassic rocks immediately overlying the dolostone to the south also suggests that the main faults seen here are pre-Mesozoic in age.
From these observations, I conclude that the faults seen here are (1) Ordovician thrust faults possibly reactivated in Triassic time to produce gouge, and (2) steep Mesozoic normal and strike-slip faults.
If it were not for the K-Ar age from the palygorskite one might suggest that the clay-gouge zones represent zones of current thrust reactivation in the present compressive stress field related to present-day seismicity. This stop illustrates well some of the complexities in correlation of seismic events with fault surfaces. Any one or all of the faults seen in this area (Stop 9, 10, 12) and shown on figure 14 might satisfy the available fault plane solutions (see fig. 2) available for this area.

At swale, trace of Mott Farm Road fault
At swale, trace of Mott Farm Road fault and cataclastite typical of Mesozoic faults trending N. 70°-80° E. View of Indian Point reactors to east.

Hornblende granite gneiss and abundant semiductile faults
Long up-grade traverses hornblende granite gneiss and abundant semiductile faults with associated lamprophyre dikes on Dunderberg Mountain.

Trace of Timp Pass fault zone
In swale, trace of Timp Pass fault zone of a composite fault zone with evidence of Proterozoic Y, Paleozoic and possible Mesozoic fault activity. This is a major fault that is traceable northeastward through the Hudson Highlands as a metamorphic semiductile fault zone. Very distinctive blastomylonite and a zone of intense folding accompanied by injection of pegmatite mark this fault in many localities. Excellent exposures here of tectonic breccia with inclusions of calcsilicate rocks in a ductile matrix of marble.

Excellent exposures of rusty paragneiss and calc-silicate rock
Note excellent exposures of rusty paragneiss and calc-silicate rock with typical Mesozoic fault fabrics. Exposures of quartz plagioclase gneiss, amphibolite and white alaskite gneiss. Numerous semiductile faults are present in this area.

STOP 13. Overlook - view of River, Dunderberg Mountain
In the nearly continuous exposures along Route 206 from the Bear Mountain Bridge south to Camp Smith numerous faults have been mapped. These faults are predominantly the semiductile type with excellent phyllonite zones and abundant evidence for right-lateral oblique thrust faulting. Correlation of tectonic features across the Hudson to Dunderberg Mountain is excellent and northeast-trending Mesozoic faults are largely absent. Mesozoic faults are predominantly north- and northwest-trending suggesting that the left-handed bend in the Hudson River here is controlled by brittle fractures of Mesozic age.
These outcrops of biotite granite gneiss are not clearly either "Storm King Granite" or "Canada Hill Granite". However, intrusive relationship in amphibolite can be seen in the roadcuts. A comparison of this rock with the "Reservoir Granite" seen at the next stop is in order.

Excellent exposures
Excellent exposures of amphibolite, alaskite, and hornblende granite gneiss ("Storm King Granite") may be seen at sharp bend in road.

Trace of Wallace Pond fault.
Entrance to Camp Smith and trace of a major semiductile fault -- Wallace Pond fault.

STOP 14. "Reservoir Granite" and mylonite zones
The "Reservoir Granite" (Berkey and Rice, 1919) is a widespread granitic rock type east of the Canopus fault zone. Doug Mose has dated a collection of rocks from this locality and from northeast of here and obtained an Rb/Sr isochron of approximately 1250 m.y. for both collections (Helenek and Mose, 1976). The granite has intrusive contacts with amphibolite with which it is commonly associated and may represent either remobilized felsic volcanic rocks (interlayered with amphibolite) or truly intrusive granite.
Excellent mylonite zones cut this garnet-bearing granite. Biotite-rich blastomylonite zones contain syntectonic garnet and intrafolial folds indicating right lateral movement. "A" lineations are subhorizontal. The granite gneiss has biotite and muscovite growing in ductile shear zones and garnet is retrogressively altered to biotite. This tectonic fabric probably represents Ordovician retrogression. The regional grade in Middle Ordovician rocks at this locality is between biotite and garnet zone.

STOP 15. Optional Annsville fault - tectonic breccia
Low road cuts of phyllite.
Exposures of marble with rounded inclusions of gneiss were cited by Bucher (1957) and by Ratcliffe (1971) as evidence for Middle Ordovician erosion beneath the "Annsville Phyllite". I have changed my opinion of this strange rock and interpret this polymict breccia as a tectonic-mylonitic breccia resulting from large-scale extension and flowage in Proterozoic shear zones. Dismembered calc-silicate rocks form the inclusion within the strongly flow-banded marble. Breccias like this are present throughout the Hudson Highlands and are not restricted to zones of Paleozoic faulting.
A fault between "Annsville Phyllite" and this marble is exposed on the north side of these cuts, where the flow-banded marble is dragged in right-lateral sense into the N. 40° E. -trending Annsville fault. Right-lateral minor folds in fluxion banded rocks and minor thrust faults suggest right-lateral, oblique thrust faulting. Exposed contacts in the sand pits to the north, reveal ribbon-quartz mylonite and diapthoritic phyllonite. Syntectonic muscovite, tremolite, actinolite, epidote, and phlogopite are formed in sheared rocks of appropriate composition.
I interpret the Annsville fault as a post-Middle Ordovician, probably Late Ordovician fault, perhaps equitable with the Thiells fault.
Numerous earthquakes have been recorded in the Annsville area, most recently in January 1980 (Fig. 1). Despite the repeated activity, faults of probably Mesozoic age are largely absent. Faults seen at the surface are all characterized by mylonitic-ductile deformation. The northeast-striking, southeast- dipping phyllonitic shear zones satisfy the available fault-plane solutions.

STOP 16. Canopus pluton and western Canopus fault
Park at aqueduct crossing. Canopus pluton and westem Canopus fault: a probable Proterozoic Y fault zone. (See figs. 16a,b,c and 17)
Road cuts of quartz monzonite and granodiorite of the Canopus pluton. Large rectangular microcline-perthite phenocrysts, showing Rapikivi-like mantles, produce a striking igneous lamination trending north to northwest. Ductile shear zones related to the Canopus fault show right-lateral drag of the older fabric. Locally small pegmatite dikes crosscut augen, gneiss and sheared igneous rocks.
The Canopus pluton has been interpreted as a Proterozoic Y syntectonic pluton on the basis of Rb/Sr and K-Ar dating by Dick Armstrong (Ratcliffe and others, 1972). The pluton is deformed in a right·lateral shear couple.

STOP 17. Mylonite gneiss in western Canopus fault
Strongly mylonitic gneiss at the eastern border of the Canopus pluton are exposed in the road cuts. Biotite-rich blastomylonite and more felsic, mylonitic, quartz-feldspar layers produce a strikingly well-layered rock. Reclined, right-lateral, isoclinal folds plunge steeply southwest in the N. 20° E., 80° SE. dipping shear fabric. A strong lineation is produced by the intersection of compositional banding and mylonitic foliation. The tectonic fabric seen here is restricted to local shear zones of Proterozoic Y age.

STOP 18.Eastern Canopus fault
Eastern Canopus fault and overprint by probable Paleozoic fault fabric of the Dlcktown fault. (See fig. 17)
Walk east to base of small cliffs.
This is a complex fault zone, consisting of pink and black biotite-rich augen, gneiss, biotite-rich blastomylonite and intrusive pegmatite. Excellent right-lateral folds, adjacent to ductile shear zones, plunge S. 45° E.
A dark-gray mafic dike crosscuts sheared gneiss and blastomylonite. Metamorphosed dikes like this one are common throughout the Hudson Highlands and are possibly of Proterozoic Z age. Chemically these dikes are distinct from lamprophyres and from Triassic diabases and are currently being, studied. No definitive age data are currently available. However, K-Ar whole-rock dates range from 900 m.y. to 240 m.y. in six samples. The fact that they are metamorphosed, locally foliated, and confined to rocks of Proterozoic age suggests that they are old dikes. A series of small mafic stocks, dikes and small plutons are recognized in the Highlands in the vicinity of the Canopus pluton. Those igneous rocks are mafic to ultramafic and always are strongly metamorphosed. These mafic rocks and plutons represent a very obscure period of igneous activity in the Hudson Highlands but appear to be post- to very late syntectonic in the Proterozoic Y deformation. Locally they are extremely abundant.
A traverse up the hill from this point is instructive and shows increasing progressive overprinting of the Canopus fault fabric by the Annsville-Dicktown fault. In the Dicktown fault zone biotite and garnet are retrograded to chlorite and chlorite rich phyllonite is common. The contrast in the metamorphic grade of a retrogressive mineral assemblages within mylonite rocks may be useful in distinguishing Proterozoic Y faults from Ordovician ones in this area. To the east the Paleozoic grade increases to sillimanite zone and mineral assemblages within mylonites of both Proterozoic Y and Paleozoic age are not distinguishable. Outcrops at this stop, however, are well within the area of relict Proterozoic Y Ar40/39 biotite ages obtained by Dallmeyer and Sutter (1976). These data suggest that the Proterozoic rocks of this area never were heated above the biotite blocking temperature of approximately 350°C since the late Proterozoic. These data are consistent with the assignment of the biotite- rich blastomylonites seen here and at Stops 15 and 16 to Proterozoic Y fault zones. Chlorite-rich phyllonite associated with the Dicktown fault, however, is probably Ordovician.
Throughout the Canopus zone east to the California Hill fault (Fig. 1), no faults having Mesozoic fault characteristics have been recognized, despite detailed mapping. However, as at Annsville, earthquakes are recorded from this zone. The event near the California Hill fault (Fig. 1) is associated with a zone of very ductile, probably Proterozoic faulting.
Faults commonly dip 80° SE. or NW. but locally may dip 60° SE. These tectonic features (Figs. 1 and 4) probably extend through the continental crust and must be present as significant inhomogeneous (weak) zones at depths of 1-10 km where earthquakes are occurring. I interpret this highly faulted zone as the ancestral grain that localized Mesozoic faulting in the area to the south traversed on the first day of this field trip. (See fig. 16c)

Exposures of "Canada Hill Granite"
Exposures of "Canada Hill Granite" and rusty biotite-sillimanite paragneiss typical of the western block of the Hudson Highlands.

Canopus Lake - crossing Denny town fault
Canopus Lake - crossing Denny town fault that marks the beginning of Canopus fault zone, crops of rusty paragneiss, amphibolite marble, calc-silicate rock, and magnetite-bearing quartzite.

STOP 19. Dennytown fault, Poughquag Quartzite inlier
(See figure 1 for location)
This exposure marks the southwestern limit of a series of faulted slivers of basement gneiss and Poughquag Quartzite that extend southwest from the front of the Hudson Highlands along the Denny town fault. These inliers are surrounded by phyllonite zones marked by chlorite-sericite-epidote mineralization and ductile fold styles. Fold axes, within phyllonite plunge southeast in 80° to 60° SE. dipping surfaces. Excellent right lateral offsets and folds are seen in thin section and outcrop. A northeast plunging "a" lineation defines the probable slip direction.
I interpret this fault as an Ordovician, right-lateral, oblique thrust fault parallel to the Proterozoic Y fabric in the gneiss. The northward extension of these fault zones is uncertain but they probably extend out into the Paleozoic cover rocks north of the Hudson Highlands.
Participants from Saturday's trip may be struck by the similarity of these exposures to the quartzite-phyllonite zone seen on Stop 1 near Boonton, N.J. This similarity should drive home the point that phyllonitic shear zones of probable Paleozoic age are regionally important features within the Ramapo seismic zone. Earthquake activity here seems to be more associated with semiductile features such as the Denny town fault than with brittle-type Mesozoic faults.

16A: RIFT TECTONICS INFERRED FROM VOLCANIC
AND CLASTIC STRUCTURES (Saturday)
WARREN MANSPEIZER
Newark, N.J.
Tholeiitic basaltic lava flows and intrusives of Late Triassic and Early Jurassic age clearly mark and distinguish the upper part of the rift-valley stratigraphic sequence in the onshore and offshore basins of eastern North America and northwest Africa. These igneous rocks were emplaced over a vast area, perhaps 2500 km long and 1000 km wide, during an episode of crustal extension and sea-floor spreading and hence exhibit a variety of structures reflecting the complex history of the basin at that time. Where these volcanics are interbedded with sediments having paleocurrent and/or paleo-environmental attributes, important conclusions may be deduced about the tectonic behavior of the basin from each rock type.
The objective of this field trip is to study a typical rift facies of interbedded volcanics and sediments, thereby providing a frame-work for interpreting the tectonics of the basin during crustal extension and sea-floor spreading. Figure 1, a diagrammatic sketch through the section, shows the kinds of structures and facies that we shall observe on the field trip. Many of these features, such as tumuli, subaqueous flow lobes and palagonite foreset bedding have not been reported from rift volcanics of eastern North America. Figure 2 shows the route of our field trip.

16A: RIFT TECTONICS INFERRED FROM VOLCANIC AND CLASTIC STRUCTURES

Sandstones and mudstones
Alternating beds of red sandstone and mudstone with a few thin interbeds of gray siltstone and dark gray to black micaceous shale, occurring below the first overpass. These siltstones yield a probable Upper Norian palynoflorule and occur about 1100 m below the First Watchung Mountain Basalt (Cornet and Traverse, 1975, p. 27). Sporadic exposures of sandstones and mudstones with fining-upward sequences, chacteristic of meandering streams, occur along Interstate 280 for the next 4.4 miles.

STOP 1. Passaic Formation: Central Basin Facies
Objective: to examine a fluvial sequence of the central basin facies.
Background: information for this stop is found in the text under, 'Central Basin Facies: Fluvial-Playa.'
Figure 22, a stratigraphic section of this stop, shows characteristics of the fining-upward sequence, namely: cut-and-fill channels, channel lag concentrates, cross-bedded arkosic sandstones, overbank deposits of reddish-brown mudstone with calcrete paleosols, gray-green to green shales with plant fragments, worm burrows, roots (?) and copper mineralization (chrysocolla and malachite.)
Petrographic and paleocurrent studies along this highway, and elsewhere in this stratigraphic horizon, indicate that the sediment was derived from a deeply weathered metamorphic terrane to the north and east., and transported to the basin across a broad southwest-sloping pediment.

Great Notch, on the western horizon
Great Notch, on the western horizon, is a 'wind gap' cut into the First Watchung Mountain by streams draining Glacial Lake Passaic.

Contact Passaic Fm / Orange Mountain Basalt.
Contact of the Passaic Formation with the overlying Orange Mountain Basalt. The columnar basalts of the lower flow unit is well exposed as is the contact with reddish-brown ripple-marked sandstones of the Passaic Formation.

Passaic Formation / Orange Mountain Basalt.
Contact of the Passaic Formation with the overlying Orange Mountain Basalt. The columnar basalts of the lower flow unit is well exposed as is the contact with reddish-brown ripple-marked sandstones of the Passaic Formation.

Beginning of the upper flow unit
Beginning of the upper flow unit with its characteristic ropy pahoehoe-pillowed surface.

Transverse cross section of subaqueous flow lobes.
Transverse cross section of subaqueous flow lobes. Note the arcuate pattern of the pillow lava complex. These structures will be examined in the lower and upper New Street Quarries at Stop 3.

STOP 2. Contact of the Orange Mountain Basalt with underlying Passaic Fm.
Objective: to determine the paleoflow direction of the lava and the paleocurrent direction of the underlying sediments.
Background: see the text under, 'paleoflow structures in rift volcanics: pipe vesicles and pipe amygdaloids.'
Figure 6 is a composite sketch of the structures found at the outcrop. The section shows the lower flow unit of the First Watchung basalt with southwest plunging pipe amygdaloids and vesicles, overlying an irregular surface of cross-bedded (southwest dipping) pebbly arkosic sandstones and conglomerates with large clasts of rounded quartzite, carbonate and shale chips. Figure 7, a stereographic projection of the paleoflow and paleocurrent data, indicates that the lava flowed to the northeast transgressing a regional sedimentary paleoslope inclined to the southwest.
This site is also of some historical importance. Alexander Hamilton, inspired by the power of the Passaic River as it cascaded over the Great Falls of Paterson, informed the New Jersey legislature that he had found the ideal site for industry in the new nation.

STOP 3. New Street Quarry
Orange Mountain Basalt: Upper Flow Unit, New Street Quarry.
Objective: to examine subaqueous volcanic structures including: pillow lavas, flow lobes, fissure eruptions, a volcanic cone (?), and zeolite mineralization. Caution should be exercised in the quarry and participants should not climb the upper quarry walls.
Background: An extensive text is developed for this stop and found under 'pillow lavas and subaqueous flow lobes'.
The walls of this quarry and an adjacent quarry, long favorites of mineral collectors for their beautiful and diversified suite of zeolites, also exhibit a splendid array of subaqueous volcanic structures (see Fig. 11). Participants should first examine the structures of the east (or far) wall, noting the amygdaloidal and vesicular upper contact of the lower flow unit and the overlying Tomkeieff sequence, which is overlain by bedded pillow lavas and a second Tornkeieff sequence. Note also spiracles in the lower colonnade and cross-sections of polygonal joint sets of the entablature. Follow the structures along the south wall, walking west, and note the increase in pillow lavas with a concomitant decrease in massive basalt. On the west wall we may observe the characteristic concave-downward arcuate form of overlapping flow lobes in transverse section. Pinching and swelling pillow buds elongated N-S in arcuate bundles distinguish the flow lobes from the overlying bedded pillows which appear to be stacked one on the other and elongated E- W.
Although the contact between the two types of pillows appears to be unconformable, the absence of eroded pillows along the contact indicates that they are conformable. Note the manner in which the younger pillows cascade off the flow lobe, building up slopes of about 40°. In general, the pillow buds are very dense with radial joint structures and few minute vesicles, indicating that they formed in deep water.
The absence of pillow-derived debris within the interstices of pillow complexes indicates that the debris was washed out of these pockets in a well-agitated lake. The occurrence of interstitial angular basaltic fragments (surrounded with quartz, calcite, perhnite and other zeolites) indicates that the fragments were derived from the checkered exterior rinds of the pillows by circulating fluids, perhaps ground water. The original debris was probably redeposited in a deeper part of the basin, along the border fault.
The flow lobe appears to flare out and to plunge westward, where it may be studied in the walls of the lower New Street Quarry. At some appropriate time, we shall enter that quarry as a group. Figure 12, a field sketch of its east wall shows three distinct episodes of vulcanism: (1) an older episode of flow lobes; (2) a medial phase of massively bedded, moderately coarse-grained igneous rock that slopes away from a central point and overlaps the distal and advancing end of a flow lobe; and (3) a younger zone of bedded pillow buds that overlie both the steep slope of the subaqueous volcano (?) and the flow lobe. The origin of these features should encourage a lively discussion.

STOP 4. Feltville Formation
Feltville Formation in contact with the overlying Preakness Basalt.
Objective: Primarily to have lunch in a pleasant setting, and secondarily to examine a fluvial-deltaic (?) facies.
Background: A stratigraphic section of this site is found in figure 23, and shows two fairly complete fining upward sequences of point bar deposition, overlain by the Second Watchung lavas along an irregular contact with pahoehoe structures, pillows, soft sediment loading structures and injection features into the underlying mud.
Note the typical fining-upward sequence with its channel deposits of coarse clastics, overlying planar beds of sandstone, which is overlain by large, low angle crossbedded sets and then by a thick sequence of ripple drift cross-laminations with shale interbeds that are cut through by a very large channel with cross-bedded pebbly sands, plant debris and thin stringers of coalified plants. The channel sands are overlain by low angle planar cross-beds, trough cross-beds and finally by fine-textured ripple drift cross-lamination. Convolute bedding and parting lineations are common with the prevailing trend of the latter striking N 5O° E. Parting lineations, in conjunction with the cross bedding, indicate that the paleocurrent was to the southwest. We can easily follow these beds to the south (using the basalt as a marker bed) where they interfinger with distributary-type channel sands of the deltaic sequence.
Look for evidence of strike-slip movement on the far wall. The pockets of pillow lavas indicate that the lava flow dammed an existing lake or stream. The pillows are perhaps best exposed in the roadway adjacent to the lunch stop, where they may be examined against the fine-splintery columnar jointing so diagnostic of the Second Watchung lavas.

First Watchung lavas and Glacial Lakes
The road is underlain by basalts of the first Watchung lavas. Glacial lakes are abundant in the area. As we proceed west onto Long Hill Road we will descend the backslope of the First Watchung.

STOP 5. Feltville Formation
Feltville Formation: subaqueous fan, marginal border facies.
Objective: to determine the provenance and depositional setting of these massively bedded conglomerates.
Background: field descriptions of this stop are found in the text under 'Marginal rift facies: fan delta'. Note figures 26 and 27. The section, about 45 m thick of coarse-grained and poorly sorted clasts with average grain size of about -4 to -6 phi (16 mm to 64 mm), occurs immediately below the base of the Second Watchung lava. The clast population has a graphic mean (Folk, 1974) of -4.5 phi and is very poorly sorted with a standard deviation of 2.4 phi (Fig. 28). The clasts are composed principally of carbonate, quartzite, low-rank metamorphics and most notably, vesicular basalt. Many of the clasts are reasonably well-rounded, imbricated, and show subtle grading which is perhaps one of the most distinctive - but elusive - aspects of this facies. In order to determine grading patterns of sedimentation, we measured the grain sizes of all clasts with a phi-ruler on a 2.5 cm sampling grid drawn perpendicular to bedding. The data, included on representative graphs of that exercise (Fig. 29) show: (1) the cyclical pattern of deposition and subtle stratification; (2) each cycle seems to begin with an inverse grading sequence, marked by a subtle increase in grain size upward in section, and followed by an abrupt decrease in grain size; (3) reverse grading is repetitive with each episode transporting slightly coarser components; and (4) many cycles are symmetrical.
Each complete depositional cycle consists of an erosional basal contact followed by a depositional couplet of inverse grading, followed by normal grading and an upper contact marked by finely comminuted particles in ripple drift cross-stratification (Fig. 26). Complete cycles are rare, and much of the section is marked by subtle and shallow cut-and-fill channels, (Fig. 27).
At the western end of the outcrop, the beds are graded and the bedding planes have a slightly arcuate pattern. Are we looking at a transverse section of a fan, or is this a drag structure along a fault?
Note that the section lacks features commonly associated with Triassic-Jurassic fluvial deposits, namely: rootlets, caliche deposits, plant fragments, dessication cracks, red beds, dinosaur footprints, worm burrows and overbank deposits.
Observe clast rounding, imbrication and composition.
Although quartzites, carbonates, and low rank metamorphics are fairly common, perhaps the most significant clasts are the vesicular basalts. Together with the imbrication direction, it suggests that the lavas of the First Watchungs flowed westward over a low-lying fault escarpment.

Most of the lakes in the area resulted from glaciation.

STOP 6. Boonton Formation (Fanglomerate).
Marginal Border Facies
Objective: To examine an alluvial fan facies within the border fault zone.
Background: Field descriptions and photographs of this section are included in the text under, 'Boonton Formation: Marginal Border Facies'.
Because the section has been polished by glacial scour, conglomeratic structures are displayed in great detail. Cyclical and laterally continuous beds of poorly sorted debris flows grading upward into cross-bedded and ripple marked sheet-flood deposits are characteristic of the section (Fig. 34). Many of the cycles are incomplete, having been partially eroded by a subsequent debris flow. Each section is about 2 to 3 cm thick and occurs within larger cyclical units of about 1.5 m thick. The clast population has a graphic (Folk, 1974) mean size of -3.3 phi, and an inclusive graphic standard deviation (Folk, 1974) of 2.2 phi (Fig. 28); it is, therefore, very poorly sorted. In general, the grains are angular and primarily composed of a quartzite, gneiss and vesicular basalt with subordinate amounts of amphibolite, slate and greenstone schists. They appear to have been derived from a local source.
Some of the primary structures seen at the section include: ripple drift cross-lamination, dessication cracks, cut-and-fill channels, normal and inverse grading, sand waves, parting lineations, antidunes (?), random fabric, sand shadows, dreikanters and oriented clasts (Fig. 33).
Particle orientation was determined from clasts having a length to width ratio of at least 1.3: 1. The prevailing long axis orientation is west-to-east with clast imbrication to the west (Figs. 31 and 32). This is compatible with a preliminary paleocurrent study showing that the clasts were transported to the basin by east-flowing streams. The occurrence of aligned ventifacts indicates that the wind was an effective agent of erosion, and may explain the deficiency of fine sand and clay size particles on the alluvial fan.

Boonton Reservoir
Boonton Reservoir on left-site of famous Boonton fish fossils.

Glacial Lake Passaic
We are traveling on the lake bed of glacial Lake Passaic, which formed as the meltwaters became impounded between the N.J. Highlands on the west, the Second Watchungs to the east and south, and the moraine to the south. At its greatest extent, the lake was 30 miles long, 10 miles wide and 240 feet deep (Kummel,1940).

Passaic River

Third Watchung lava flow on S horizon (see Olsen, this book).

Backslope of the Second Watchung lava flow.
Coarse-grained diabasic texture may be examined near upper part of the exposure.

Lava / Feltville Fm contact
Contact of lava flow with the underlying Feltville Formation. Note the fine-textured joints of the entablature. When exposed during road construction, the formation consisted of cross-bedded feldspathic sandstone (10 m) underlain by thin stringers of coal with underclay. A similar section may be studied in the parking lot of the Daughters of Israel Nursing Home, 1155 Pleasant Valley Way, West Orange (about 3/4 mile south).

Backslope of the first Watchung lava flow
Outlines of pahoehoe toes may be studied in roadcut.

STOP 7. Orange Mountain Basalt; lower flow unit
Objective: To examine a Tomkeieff sequence of colonnades and entablatures near the classical site of O'Rourke's Quarry. (See photograph facing the title page of this article.)
Background: This structure is described in the text under 'Columnar Jointing'.
When built in 1969, this road cut was the deepest federally-financed highway cut east of the Mississippi River. About 33 m deep, the cut exposes a complete section of the lower flow unit of the Orange Mountain Basalt, and a broad array of joint patterns that formed as the basalt cooled. The large "basin" structure on the southeast wall was first described about 100 years ago by J.P. Iddings (1886) of the U.S. Geological Survey in John O'Rourke's Quarry, about 300 m south of the roadcut. While such complete structures have not been observed elsewhere in the Watchungs, similar joint structures, e.g. chevrons, oblique and reverse fans and rosettes (terminology of Spry, 1962) may be studied in this roadcut and in almost every quarry along strike for a distance of 80 to 100 km.
This structure (about 33 m thick) conformably overlies a fluvial red bed sequence of shales and sandstones and, when first exposed, displayed a complete Tomkeieff sequence of: (1) a lower colonnade (10-15 m); (2) entablatures (20-30 m); and (3) an upper colonnade (1-2 m) (Fig. 17). While the lower colonnade is composed of massive 4-5 or 6-sided polygonal and subvertical prisms, the entablature is composed of long (25-30 m) slender narrow joint prisms that radiate from an apparent focus. Several juxtaposed bundles or sheafs of radiating prisms may be observed in the roadcut, comprising fan and chevron-like features. Cross joints, intersecting radiating prisms at high angles, are prominent and appear to be concentrically arranged about the apex of radiation. An incomplete section pseudo-columns overlie the entablature.
Figure 18, depicting mineral and textural variations within the structure, shows an increase in grain size, an increase in the abundance and size of the interstitial glass, and an increase in the olivine content in the entablature (Fig. 19). This suggests that although cooling may have proceeded very slowly from the sediment-volcanic interface, once a ground mass capable of transmitting stress was established the remaining melt cooled almost instantly. The obscure joint pattern in the upper colonnade may form from convective heat loss near the upper part of the flow.
The early cooling history of the magma is manifested by well-developed horizontal striations observed on the joint surfaces of the lower colonnade. While Iddings (1886) may have been the first to report horizontal striations on joint surfaces (from O'Rourke's quarry), James (1920) speculated that these striations represent successive stages or pulses in which the rock broke and the columns formed. Recent studies by Ryan and Sammis (1978), and Justus and others (1978) at this site show that the striations are records of discrete thermal events, characterized by sudden periods of crack advance in the cooling basalt. Features such as chisel marks, pinch and swell and kink structures on the curvi-columnar joints may also represent an episodical cooling history. Each of these features may be observed on the walls of the highway cut.
The striations reported by Iddings (1886) show up on joint surfaces of the lower colonnade as cyclical bands of smooth and rough zones, about every 5-7 cm. Ryan and Sammis (1978) report that as the crack growth proceeds, the first-formed zone is smooth and associated with a thermal shock event; the second zone is rough, has positive relief, and is associated with the halting of each crack advance.
Joints of the entablature are also cut by concave-upward "dish-like" joints that are cut by strike-slip faults. While the origin of this structure is debatable, it trends N 50° E and evidently formed after the basalt cooled and before faulting occurred.

Dike intrusion into fluvial channel sands.

16B: RIFT TECTONICS INFERRED FROM VOLCANIC
AND CLASTIC STRUCTURES (Sunday)
WARREN MANSPEIZER
Newark, N.J.
Tholeiitic basaltic lava flows and intrusives of Late Triassic and Early Jurassic age clearly mark and distinguish the upper part of the rift-valley stratigraphic sequence in the onshore and offshore basins of eastern North America and northwest Africa. These igneous rocks were emplaced over a vast area, perhaps 2500 km long and 1000 km wide, during an episode of crustal extension and sea-floor spreading and hence exhibit a variety of structures reflecting the complex history of the basin at that time. Where these volcanics are interbedded with sediments having paleocurrent and/or paleo-environmental attributes, important conclusions may be deduced about the tectonic behavior of the basin from each rock type.
The objective of this field trip is to study a typical rift facies of interbedded volcanics and sediments, thereby providing a frame-work for interpreting the tectonics of the basin during crustal extension and sea-floor spreading. Figure 1, a diagrammatic sketch through the section, shows the kinds of structures and facies that we shall observe on the field trip. Many of these features, such as tumuli, subaqueous flow lobes and palagonite foreset bedding have not been reported from rift volcanics of eastern North America. Figure 2 shows the route of our field trip.
This trip contains only those places not visited on trip 16A.

16B: RIFT TECTONICS INFERRED FROM VOLCANIC
AND CLASTIC STRUCTURES (Sunday)

STOP C. Lower Flow Unit Preakness Basalt.
Objective: To examine tumuli (also known as pressure domes or schollendomes, Macdonald, 1953).
Background: Information about this structure is found under Tumulus, also figures 8 and 9. The exposed tumulus structure, about 7 m high and 15 m wide, consists of a central core of massive basalt with columnar joints (1-1.5 m wide), an overlying zone of radiating entablature joints (0.5-1.0 m wide), and an upper colonnade with poorly defined columnar joints and vesicular to brecciated basaltic glass. The structure is overlain by a pillow-pahoehoe complex that thins along its crest and thickens along its flanks and adjacent troughs. A second flow unit overlies both structures and consists of massive colonnades with bent pipe amygdaloids, indicating that the lava flowed towards the crest of the tumulus. Although this tumulus did not feed the second flow unit, it appears to have fed (through the overlying brecciated zone) the pillow-pahoehoe complex.
The section also shows an interesting assemblage of ellipsoidal bunlike structures, including: pahoehoe toes with concentric layers of vesicular and non-vesicular basaltic glass, and with flat bottoms and rounded tops; (2) flattened lava tubes (?) with concentric structures and hollow interiors in transverse cross section; and (3) pillow buds with circular transverse sections and ellipsoidal longitudinal sections, vesicular cores and pipe amygdaloids elongated radially near the bud edge. and radial and concentric joints in cross section. Moreover, note: the variety of bun shapes and sizes; the volcanic debris separating these bun-like structures; the occurrence of several tumuli crests at different heights along the exposures; and the surface topography of the lava flow as expressed by the tumulus surface.
Did this structure form in water? When did it form relative to the pillow-pahoehoe complex? How do these bun-shaped structures compare to those at the New Street Quarry? Are the buds a tangled mass of independent sack-like structures or a tangled mass of cylindrical interconnected pillow buds, lobes and pahoehoe toes? What does the structure tell us about the relationship between topography, isotherms and the formation of columnar joints. We shall continue our discussion of this point at our next stop.

2nd flow unit of the First Watchungs
Vesicular pahoehoe flows of the 2nd flow unit of the First Watchungs behind stores on right.

A wind gap cut into the First Watchung Basalts.

Eagle Rock Reservation. Park Buses -Lunch Stop.

Trap rock quarry
Trap rock quarry, entablature structures may be seen from the road.

Red beds with fining upward cycles.

Entering the South Mountain Reservation
Back slope of the First Watchung Mountains on the left (east); the Second Watchung Mountain on the right (west).

STOP E. Feltville Fm contact Orange Mountain Basalt.
Feltville Formation in contact with the underlying Orange Mountain Basalt.
Objective: Primarily to determine whether the second flow unit is intrusive or extrusive. And secondarily to examine the carbonate sequence near the base of the Feltville Formation.
Background: This section is discussed in the paper under 'Emplacement of the Watchung Lavas', and 'Central Basin Facies: Lacustrine-Deltaic Facies', see figure 20. The issue before us at this site is the same as the one confronted by a group of eminent geologists more than 100 years ago, including: Cooke (1868), Russel (1878), Davis (1882) and others. Figure 20 will be helpful in your examination. Note the irregularity of the contact, the 'baked' mudstones and sandstones, vesicular sandstones, the occurrence of marble float along the carbonate horizon, the occurrence of pillow lavas, and the stratification in the basalt. Moreover, note pillow vesicularity, pipe vesicles and amygdaloids elongated radially near the bud edge, and brecciated clasts of basalt and red beds within pillow interstices.
Are the pillow buds independent sack-like structures or are they interconnected cylindrical-to-sack-like masses? Do they rest directly upon each other, or are they separated by baked sediment, weathered sediment or basalt, or an old soil horizon? Is the basalt stratification a relict sedimentary structure or a primary volcanic structure? Is the irregular sedimentary-igneous contact an old soil horizon or an intrusive-baked contact? Recall that this horizon is stratigraphically equivalent to the section that we studied at the New Street Quarry.
Upstream the pillow buds become larger, more numerous, bedded, and overlain by a complete Tomkeieff sequence. This part of the section is quite similar to the upper part of the section at New Street.
The second reason for examining this section is to study the sequence of shelf carbonates and siltstones that unconformably overlie the basalt, and crop out sporadically from Feltville to Pluckerman's Ravine.
The carbonates occur as thin discontinuous limestone lenses, about 5-20 meters above the igneous contact, and interbedded with gray and reddish-brown shale and gray calcareous thinly laminated siltstone. A trench dug into the hillside exposes the section (Fig. 24)(McGowan. 1980). The limestones, about 10 cm thick and 100 m long, display a variety of shallow water structures including: cross-bedding, dessication cracks, rounded intraclasts cemented with sparry calcite, ripple marks, abraded algal debris and erosional lower contacts. Although some of these features are ambiguous with respect to environments of deposition, the assemblage of structures point to a shallow water carbonate bank. See also McGowan (1980), who has made an extensive study of this formation. Olsen (pers. comm.) also reports the occurrence of thinly laminated deep-water carbonates with whole fish fossils stratigraphically beneath the shelf carbonates. Plant fragments, dinosaur footprints, fish fossils, algal mats, ostracods, and one branchiopod shell are reported from this section (Olsen, 1975; Dahlgren, 1975; McGowan, 1980). Flaser bedding, ripple drift cross-laminations, parting lineations and small scale trough cross beds may be observed in the overlying siltstones and sandstones. The average direction for the trough cross beds and parting lineations is 180° and 145° respectively (McGowan, 1980).

17: FOSSIL GREAT LAKES OF THE NEWARK SUPERGROUP IN NEW JERSEY
PAUL E. OLSEN
Bingham Laboratories, Department of Biology
Yale University, New Haven, Connecticut
Because Newark Basin lacustrine rocks are (1) often composed of sedimentary cycles, (2) traceable over very large areas, and (3) unusually rich in fossil remains, they are among the most interesting and challenging of Newark Supergroup deposits. While lacustrine sequences are found in all sedimentary divisions of the Newark Basin, those of the Lockatong, Feltville, and Towaco formations are known in greatest detail and are therefore the focus of this field trip. I concentrate on the interpretation of the lake sediments, paying special attention to some fundamental problems in their interpretation. In addition, I touch on some relevant paleozoology.
2011: Views along I 80,which duplicate those from NYSGA 1980 Trip 1, have not been reproduced here.

17: FOSSIL GREAT LAKES OF THE NEWARK SUPERGROUP IN NEW JERSEY

Passaic Formation
Newark Campus sits on late Norian or earliest Rhaetic sandstones and siltstones of the Passaic Formation.

Newark Museum on left

Along the strike of the Passaic Formation.
Route 21 follows the west bank of the Passaic River along the strike of the Passaic Formation.

Pass Belleville Avenue
Just north of Belleville Avenue and 1.1 miles east of Route 21 is the old Schuyler Copper Mine worked from about 1720 to about 1900 (Lewis, 1906). The ore occurs in gray arkosic sandstone and gray siltstone invaded by small dikes and sills of diabase. Lewis (1906) lists chalcocite, chrysocolla, and malachite as the major copper minerals with minor amounts of azurite, cuprite, and native copper.

Fragments of phytosaur skull
Fragments of phytosaur skull and reptile footprints found in Passaic Formation "brownstone" quarry near here (Edwards, 1895; Lull, 19S3).

Route 3 cuts across strike through Passaic Fm.
Route 3 cuts across strike through Norian and Late Carnian Passaic Formation. This portion of the Passaic Formation is the lateral equivalent of the entire Delaware River section of the Passaic and upper Lockatong (see Van Houten, this Fieldbook)

Entering Hackensack Meadows.
About 0.2 mi. southwest of this point are excellent exposures of Passaic Formation including a series of gray sandstone beds (ca. 2 m) stained with chalcocite, malachite and azurite. Old (?exploratory) shafts are evident in the outcrops. Lithology of copperbearing units very similar to beds at Schuyler Mines. I have found reptile footprints assignable to Rhynchosauroides brunswickii and Grallator sp. and in addition, horseshoe crab tracks called Kouphichnium and Scoyenia burrows in the fine red siltstones surrounding the gray sandstone. Lower red beds of exposure contain well developed caliche horizons similar to those described by Hubert (1977) from more or less contemporary beds of the New Haven Arkose (Hartford Basin). Further southwest, (0.3) mi are additional exposures along former Erie Lackawanna Railroad tracks showing an unusual reverse fault dipping to the west and downthrown on the east. Slickensides confirm the dipslip nature of the fault. Hackensack Meadows, over which Route 3 crosses, are underlain by relatively finegrained red and minor gray beds of Passaic Formation.

Lateral equivalent of Graters Member?
Ridge just south of here (Secaucus) has exposures of gray sandstones and siltstones which could be lateral equivalent of McLaughlin's (1948) Graters Member.

Open cut in Stockton Formation
On right is open cut in Stockton Formation and west portal of tunnel for Penn Central Railroad. Cut exposes upper Stockton beds described by Darton (1883). At east end of cut at tunnel is excellent exposure of the contact between the Stockton Formation and the Palisade Diabase. Stockton beds dip at 15° NW while the irregular contact dips at 60° NW. This contact is locally welded according to Darton (1890) and Lewis (1908). This is one exposure where the Palisade Sill is described as having a dike-like appearance. Actually, these exposures and similar ones nearby are perhaps better explained by a local stepping up of the Palisade Sill as shown in Figure 26.

Stockton / Palisade Sill contact
Contact of uppermost Stockton with Palisade Sill directly on right (east). Stockton dips 15° NW and the contact dips 45° to 80° NW. This appears to be a continuation of the contact surface exposed at the Penn Central tunnel previously described. Recrystallized arkose of Stockton Formation is sheared and dragged upwards close to contact with fine slickensides indicating down-dropping to the west. There are no indications of movement in the diabase, however. Basal Lockatong hornfels 100 m to the north, dip 15° NW and lie concordantly on the Palisade Sill. A possible interpretation of these exposures might be that the apparent movement in the Stockton occurred during intrusion of the sill.

Dip slope of Palisade Sill
Dip slope of Palisade Sill mantled by northwesterly dipping Lockatong Formation. Contact appears concordant from here to Granton Quarry.

STOP 1. Abandoned Granton Quarry
Abandoned Granton Quarry in lower Lockatong Formation hornfels and overlying Granton Sill. Turn left off Route 1 and 9 into parking lot for Shop-Rite employees at Diana Stores Corporation.
Eleven Lockatong cycles are exposed on the sill-capped hill: seven are exposed on the south facing exposure (Figure 27); three additional cycles are exposed on the east facing exposure; and all 11 cycles are exposed on the north facing exposure but are not accessible without special permission. The base of the section appears to be 38 - 46 m above the contact with the Palisade Sill (Van Houten, 1969). This contact may be following what was, prior to intrusion, the Stockton-Lockatong contact.
According to Van Houten (1969) these Lockatong hornfels include calc-silicate varieties in the middle carbonate-rich part, and extensively feldspathized and recrystallized diopside-rich arkose in the upper part. Some beds of arkose show well developed crossbedding (Figure 28). Because of the buff arkose at the top of nearly every cycle, these are the most visually graphic of the detrital cycles seen on this field trip; here the many correlated changes occurring though individual cycles can be easily seen (Figure 29).
Cycles 3 and 7 (Figure 29) have produced representatives of all the known (skeletal remains of) Lockatong holostean Semionotus, and the amphibian Eupelor. The basal portions of division 2 of both of these cycles have extremely high densities of fossil fish, especially the coelacanth Diplurus newarki Schaeffer (1952). Small reptiles are also surprisingly abundant (Figure 30). Many important fish and unique reptile skeletons have been discovered here by dedicated amateurs, and donated to various museums through the years (Colbert, 1965, 1966; Schaeffer, 19S2; Schaeffer and Mangus, 1971; Colbert and Olsen, In Prep.; Olsen and Colbert, In Prep.).
At the south-facing exposures, cycles 1 and 2 are broken and injected by diabase of Granton Sill (Van Houten, 1969). Notice the absence of prominent folding at the diabase-sediment contact. The total thickness of the sill is 20m.
One or two bedding plane thrust faults, always thrusting to the east, are present in division 2 of nearly every cycle at Granton Quarry, Slickensides are usually present and indicate that movement occurred parallel to dip. All joint sets are cut by these thrusts, their displacement indicates each fault has a net slip of .5 to 1.5 cm. This type of minor thrust fault is evident in virtually all Newark Supergroup lacustrine cycles and can be seen at every stop of this trip.

Lockatong hornfels and Palisade Sill
Cloverleaf at this intersection rests on Lockatong hornfels and Palisade Sill (Fluur, 1941).

Open cut for Route 495 in Palisade Diabase.
Construction of cut exposed a number of easterly down-dropping dip slip faults which were described by Fluur (1941).

Reentrant in Palisade Escarpment
Reentrant in Palisade Escarpment at this point created by differential weathering along a series of dip slip faults, the cumulative dip slip amounting to about 70 - 80 m.

One of the larger faults
This street parallels one of the larger faults, in this case one responsible for the abrupt truncation of the western portions of Kings Bluff directly to the left (east) (Flurr, 1941).

Small fault striking nearly E-W.
According to Fluur (1941), construction along this road revealed a small fault striking nearly E-W.

STOP 2. Kings Bluff, Weehawken.
East face of Palisade ridge with exposures of long series of Lockatong cycles, tongues of Stockton-like beds, and alternating concordant-discordant contacts with the Palisade Sill. Park in lot on west side of road near the railroad tracks.
This is the first of three stops designed to show the lateral continuation of individual detrital cycles and the lateral change in sedimentary and metamorphic facies.
Lockatong and Stockton sediments and their contacts with the Palisade Sill are exposed at numerous places along the Palisade escarpment from Hoboken, New Jersey to Haverstraw, New York. Study of these exposures is permitting a cycle-by-cycle correlation of the Lockatong for at least 15 km of this distance, the cycles mapped so far are designated informally in Figures 31, 32, and 33. To the south at Hoboken the Palisade Sill rests near the base of cycles 5 and 6 (Figure 31). To the north towards the Lincoln Tunnel Toll Plaza, the contact drops more than 250 m into the Stockton Formation. At Kings Bluff, this contact abruptly rises again to cycle 0, staying within division 2 of this cycle for at least 300 m north. The olivine zone of the Palisade Sill produces an obvious bench along the escarpment, essentially paralleling the lower contact of the sill as observed by Walker, 1969 (Figure 31).,
Note the thin sill which branches off from the main sill intruding between cycles a and b. This sill definitely runs north for at least 400 m and was encountered during the excavations for the ventilation buildings for the Lincoln Tunnel (Figure 31) (Fluur, 1941). It may go at least another 200 m (Figure 36).

STOP 3. Gorge and River Roads
Gorge and River Roads exposures of cycles 1' - 6 and a and b. Turn right into empty lot outside entrance for Celotex Corporation.
Cycles 1 - 6 exposed along Gorge Road and cycles a-c on west side River Road opposite Mobil Service Station (Figure 37). These are the same cycles seen at Stop 2. Cycles 5 and 6 are virtually unchanged with the exception of an increase in ostracod density in the upper parts of division 2 of both cycles, fewer fish in division 2 of cycle 6, minor color changes, and the presence of calcareous nodules in division 2 of cycle 5. Cycles 1,3, and 4 appear unchanged from Stop 2, while cycle 1' is less disturbed and cycle 2 has more fish than at Stop 2.
In contrast with the relative lack of change from Stop 2 in cycles 1'-6, the siltstone units between cycle 6 and cycle a (Figures 32 and 33) are nearly completely replaced by 5.5 m of arkose with cross-bedding indicating transport to the west and southwest (Van Houten, 1969). I believe this arkose tongue and the thin siltstones present in this interval at Stop 2 to be the lateral equivalent of chemical cycles present in the central Newark Basin. Cycles a and b appear virtually the same as at Stop 2.
The detailed correspondence between beds and vertical changes in lithology and paleontology in cycles 5 and 6 (Figure 38) between Stops 2 and 3 is illustrative of the large area over which the factors responsible for the details of the cycles operated. The region represented by stops 2 and 1 was evidently far enough from shore (during the deposition of division 2) that the normal heterogeneous depositional environments of the shore had virtually no influence on cycles 5 and 6. This, in turn, is indirect evidence that the size of the lake which produced cycles 5 and 6 was considerably larger than the 15 km traced so far.
Note that Gorge Road follows fault-line ravine north of Lockatong exposures; eastern block is downthrown about 53 m (Van Houten, 1969).

Large xenoliths exposed on left (west)
Large xenoliths exposed on left (west) in excavation behind Virginia Lee Lace Co. (Van Houten, 1969).

Passing over eastern portal of tunnel
Passing over eastern portal of tunnel for former New York Susquehanna and Western Railroad. Directly under bridge for River Road is complete section of Lockatong cycles 1 '-6 and a. This same section is then repeated by a fault striking north. Cycle 2 is unusually fossiliferous, producing large numbers of well preserved Turseodus and fragmentary large Diplurus. At west portal of tunnel is a large open cut in upper Stocton and lower Lockatong. Contact with sill dips 65° NW while Stockton and Lockatong dip 15° NW.
These exposures appear to be a repeat of the pattern seen at mileages 13.6 and 14.3 as shown in Figure 26.

Old quarry on left
Old quarry on left with excellent exposures of cycles 4 - f and underlying Stockton Formation. Small fault exposed at back of quarry which drops down the western block.

Series of outcrops along abandoned trolley route
Up hill on left on west side of Undercliff Avenue is long series of outcrops along abandoned trolley route (Van Houten, 1969). Exposures include upper Stockton Formation and lower Lockatong including cycles 5 and 6 and a, b, and c. The base of Palisade Sill is well exposed with large xenolith of cycle 5 suspended about 5 m above Lockatong-sill contact. Cycle 5 below contact contains scapolite-aegirine and Na-feldspar hornfels, while xenolith of same unit consists of very course grained biotite, Na-feldspar hornfels with minor pyroxenes, and beds of cordierite, biotite Na-feldspar hornfels (Van Houten, 1969).

Large phytosaur skeleton
A significant portion of a large phytosaur skeleton was found in upper Stockton beds near here in 1911. The skeleton, named Rutiodon manhattanensis by Friedrich von Huene (1913), is not generically determinate because it lacks a skull.
Reentrant in Palisade escarpment at this point is due to a few east dipping normal faults.

Olivine zone of Palisade Sill on left.
Diabase below olivine zone has distinct laminated appearance.

Contact of Palisade Sill with Lockatong Fm.
Irregular contact of Palisade Sill with Lockatong Formation -stratum uncertain (Figure 39).

Lockatong-sill contact
Additional exposures of Lockatong-sill contact on left - largely conformable. On the right, at the base of the hill, is a foot path along which are exposures of buff arkose and red and purple siltstone of the upper Stockton Formation. These are the most southerly exposures of a facies of the Stockton Formation visible along the Hudson from here to Haverstraw, New York (Olsen, Baird, Selden, and Salvia, In Prep.).

Circle in park road at base of shear face of Palisade Sill.

STOP 4. Ross Dock, Palisade Interstate Park
Lunch and extensive exposures of cycles 1' - 6 and a - c and irregular lower contact of Palisade Sill. Park in lot, have lunch, then take stone steps up hill (west) to road at level of circle (River Road of park) and walk north along road to exposures of Lockatong (Figure 40).
Proceed north along road, slowly walking down section (Figures 40 and 41). Cycle 1' and overlying 4 m of arkose with no sign of cycle 0 which presumably pinched out or was cut out south of here. Cycle 1 is present but poorly exposed. Cycle 2 is very well exposed and contains the same fossils as at mileage 24.8, although there are fewer whole Turseodus. Cycles 3 and 4 are evidently replaced by buff, crossbedded arkose. Cycles 5 and 6 very well exposed. Middle part of division 3 of cycle 6 contains distinctive nodular calcareous bed resembling caliche. Cycle 5 still shows the same basic sequence of beds and vertebrates as previous stops, but cycle 6 is noticeably coarser with fewer less well laminations and there are less fish. Upper division 1 of cycle 6 has produced a partial arthropod of uncertain relationships about 20 cm long.
The tongue of buff arkose between cycles 6 and a is thinner than at Stop 3 and coarsely crossbedded. Lower arkose cuts down into cycle a at this exposure, eliminating its division 2 (Figure 42). Mean paleocurrent vector for these crossbeds is N 59° W (based on 8 readings).
Cycle a is penetrated by numerous Scoyenia burrows (which were definitely not present at mileage 26.3) as are what appear to be cycles b and c. We are clearly in the shallow water facies of division 2 of cycles a - c at this point but only just leaving the deep water facies of division in cycles 2, 5, and 6.
Cycle a shows well developed fracture cleavage in division 1. Cleavage dips 25° to 30° and strikes S 78° W. Cleavage is strata-bound but discontinuous, passing laterally into breccia or non-cleaved beds. What is the significance of these structures?
The facies trend in the Lockatong from Stops 2, 3, and 4 is from a more central basin facies to a marginal facies. The monotony in horizontal continuity gives way laterally to heterogeneity (Figures 33 and 38). Those cycles with the best developed microlaminae and the best preserved fish at Stop 2 are also those which persist the longest with the least change.

Towaco Formation
Proceed on Route 46 west over broad flat expanse of Towaco Formation mantled by Pleistocene and Recent deposits.

Type section of Hook Mountain Basalt is on right
Type section of Hook Mountain Basalt is on right (north) in cuts for Hook Mountain Road and Route 80. Pass into Boonton Formation.

Buried portion of Hook Mountain Basalt
In this area we cross back over buried portion of Hook Mountain Basalt which links up Riker Hill and Hook Mountain (see Olsen, this Fieldbook).

Contact between Towaco Fm and Hook Mountain Basalt
Excellent exposures on left (east) of contact between Towaco Formation and Hook Mountain Basalt in Nob Hill Apartment complex (former east half of Roseland (Riker Hill Quarry). Two flows of Hook Mountain Basalt visible here (cumulative thickness 110m).

Follow along the back slope of Riker Hill.

STOP 5. Geology Museum, Walter Kidde Dinosaur Park
Geology Museum and Walter Kidde Dinosaur Park (former west side Roseland (Riker Hill) Quarry). Park in lot and look over exhibits at Geology Museum. Then take access path from Geology Museum over the crest of Riker Hill and down, through wooded area into Dinosaur Park. Always get permission before entering park.
As it stood in 1975, the Roseland Quarry occupied 55 acres, exposed 95 m of upper Towaco Formation - including two complete Towaco cycles, and exposed about 50 m of the overlying Hook Mountain Basalt (Figures 43 and 44). The quarry became very well known in the late 1960's and early 1970's for its prolific dinosaur footprints. Because of the scientific and educational potential of the site the then owners, Walter Kidde and Co. Inc., donated the most productive 15 acres to the Essex County Park Commission. The site now awaits development.
Before the other 40 acres were developed as the Nob Hill development, the following features could be seen:
1 , lateral changes in facies within divisions 1 - 3 of the lower cycle (Figure 45). The microlaminated beds of division 2 produced many fossil fish, all Semionotus (Figure 46) as did a number of the thinner (30 cm) turbidites.
2 , two upwards coarsening turbidite sequences, the lower being by far the larger (Figure 45). The lower sequence shows large scale slumped beds resembling "wild flysch" associations. Some of the "roll over" structures are 2 to 3 m in diameter. Transport was from the east.
3 , abundant dinosaur footprints in possible crevasse splay (in division 3) of channels about 70 m to north of tracks (Figure 47). Orientation of trackways proved to be parallel to paleocurrent directions derived from ripple marks within the footprint-bearing bed and oriented plant debris in overlying beds.
4 , Series of 7 fining-upwards cycles of division 4 of the lower Towaco cycle in the Quarry. Middle3 cycles had extensively developed dolomitic nodules and deeply mudcracked beds. Second fining-upwards cycle from the bottom with laminated silty beds (?flood basin) with abundant clay filled root casts, many of which are surrounded by dolomitic nodules (Figure 48).
In the presently exposed beds the following can be seen:
1, uppermost fining-upwards cycle of lower Towaco cycle still exposed along eastern boundary of park. The upper and middle parts of this cycle have the best reptile footprints in the quarry and hold the key to the park's development. Footprints are especially abundant in interbedded sequences of possible crevasse splay sandstone and flood basin siltstone. Basal sandstone portions of cycle are locally deeply down cut into underlying beds and contain beds of mud-chip conglomerate and casts of tree limbs and roots. Uppermost portions of the cycle consist of fine siltstone transitional into the lower parts of division 1 of the upper Towaco cycle. Transitional beds with numerous red siltstone roots surrounded by greenish halos.
2, exposure of complete Towaco cycle. Division 1 contains prominent fine sandstone beds with large calcareous concretions which weather out to form limonite filled cavities and extensive large (1-4 cm) coalified roots which probably belong to conifer trees. Crevasse splay beds in division 1 covered with little dinosaur footprints. Identical beds occur in division 2 of this cycle exposed in Chatham, New Jersey, 13 km south of here.
3, microlaminated portion of division 2 has very well developed white-black microlaminae (Figure 15) - but no fish have been found yet, however. Upper parts of microlaminated beds contain distinctive nodules of black chert. Black, coally-looking siltstone surrounding chert bed has several bedding thrusts similar to those seen in the Lockatong at Stops 1 - 4. Microlaminated beds locally involved in disharmonic folds (Figure 15). Like the beds of division 1, these portions of division 2 look exactly the same in the Chatham exposures.
4, casts of a salt present in coarse siltstone beds above microlaminated portion of division 2.
5, massive fine gray siltstone in upper parts of division 2 have well-preserved conifer foliage, pollen and spores, individual fish scales (Semionotus), and rare insect fragments.
6, complex series of sandstones and siltstones of division 3 showing features suggestive of both laterally migrating channels and prograding deltas.
7, lowest fining-upwards cycle in division 4 (Figure 49) shows slip-off faces of point bar and beds of intraformational conglomerate with coprolites, fish scales, reptile bone fragments, and abundant dinosaur footprints. The latter features could represent a dinosaur "wallow".
8, 10 successive fining-upwards cycles of division 4. Rill marks very well developed in bank portions of one of the middle cycles (Figure 50) These sorts of rill marks, typical of channels with rapidly dropping water levels, have long been confused with plant remains (it is easy to see why) and have received the name Dendrophycus (Newberry, 1888).
9, unique small reptile footprints with structure highly suggestive of advanced mammal-like reptiles or mammals (Figure 20) are present in upper fining-upwards cycles. If they do represent mammals,they will be the oldest North American record.
10, very badly weathered "tuff" between normal Towaco Formation and Hook Mountain Basalt. This unit is enigmatic but very widespread at this stratigraphic position. Fresh exposures were described by Lewis in 1908 (see Olsen; this Fieldbook).

Preakness Mountain Basalt
Head east on 280 up dip slope of Preakness Mountain Basalt. Outcrop width of Preakness Basalt is very large in this area, suggesting a thickness of 500 m for the basalt. I believe this is due to a number of small strike faults and the true thickness is closer to 300 m. These faults in combination with the multiple flow character of the Preakness Basalt produced the many small ridges visible while driving up the dip slope.

Type section of the Preakness Basalt
Type section of the Preakness Basalt in deep open cut for Route 280. Section exposes about 100 m of the lower flow. Note distinctive "splintery" nature of the lower 50 m (see Olsen, this Fieldbook). This section is cut by a series of faults all apparently left lateral and all showing little or no apparent dip slip offset (Figure 51).

Preakness Basalt / Feltville Fm contact
Contact between Preakness Basalt and Feltville Formation poorly exposed on south side of road.

Unexposed contact
Unexposed contact between Feltville Formation and underlying Orange Mountain Basalt below this point.

Exposures of ?second flow of Orange Mountain Basalt.

Type section of Orange Mountain Basalt
Type section of Orange Mountain Basalt in very long and deep open cut for Route 280 (see Olsen, this Fieldbook; Manspeizer, this Fieldbook). Section exposes about 55 m of lower flow as well as a number of left lateral faults similar to those seen at mileage 64.8. Left lateral faults are present here as they are at mileage 64.8. At one portion of the cut, on the north side is 20 m long horizontally slickensided fault plane. Note the very different appearance of basalt (in terms of jointing) from the Preakness Basalt.

Contact Orange Mountain Basalt / Passaic Fm
Contact of Orange Mountain Basalt and Passaic Formation was well exposed during construction of this cut, at this point.

Triassic-Jurassic boundary
Cuts in uppermost Passaic Formation here have produced phytosaur footprints called Apatopus and the possible crocodillo-morph tracks called Batrachopus. The Triassic-Jurassic boundary lies somewhere within the upper few tens of meters of the Passaic Formation here.

Passaic Formation formerly exposed here
Sedimentary cycle in Passaic Formation formerly exposed here. A very well preserved palynomorph assemblage recovered from fine gray siltstones of this unit suggest a lower Rhaetic age (Comet, 1977). This unit has also produced a series of reptile footprints including large and small Grallator and Chirotherium sp. Scoyenia is abundant as is the conchostracan Cyzicus. Equivalent beds are exposed at the same stratigraphic position in New Brunswick, New Jersey. The entire Passaic Formation section from this unit to the Orange Mountain Basalt is above the entire Delaware River section of the Passaic Formation, which extends upwards only into Norian beds (Cornet, 1977).