NYSGA 2010
New York State Geological Association
82nd Annual Meeting
Field Trip Guidebook
Hosted by
College of Staten Island/CUNY
Staten Island, NY, 10314
Edited by
Alan I. Benimoff
Published by the
www.nysga.net
www.nysgaonline.org

1: DELAWARE WATER GAP, A GEOLOGY CLASSROOM
Jack B. Epstein
U.S. Geological Survey
Introduction
The Delaware Water Gap National Recreation Area (DEWA) contains a rich geologic and cultural history within its 68,714 acre boundary. Following the border between New Jersey and Pennsylvania, the Delaware River has cut a magnificent gorge through Kittatinny Mountain, the Delaware Water Gap, to which all other gaps in the Appalachian Mountains have been compared. Proximity to many institutions of learning in this densely populated area of the northeastern United States (Fig. 1) makes DEWA an ideal locality to study the geology of this part of the Appalachian Mountains. This one-day field trip comprises an overview discussion of structure, stratigraphy, geomorphology, and glacial geology within the gap. It will be highlighted by hiking a choice of several trails with geologic guides, ranging from gentle to difficult. It is hoped that the "professional" discussions at the stops, loaded with typical geologic jargon, can be translated into simple language that can be understood and assimilated by earth science students along the trails. This trip is mainly targeted for earth science educators and for Pennsylvania geologists needing to meet state-mandated education requirements for licensing professional geologists. The National Park Service, the U.S. Geological Survey, the New Jersey Geological Survey, and local schoolteachers had prepared "The Many Faces of Delaware Water Gap: A Curriculum Guide for Grades 3–6" (Ferrence et al., 2003). Portions of this guide, "The Many faces of Delaware Water Gap" appear as two appendices in this field guide and is also available by contacting the Park The trip will also be useful for instruction at the graduate level. Much of the information presented in this guidebook is modified from Epstein (2006, 2010).
Please note: It is illegal to collect rocks, plants, or parts of animal life in National Park lands.

1. Delaware Water Gap, A Geology Classroom

View of Delaware Water Gap on right.
Crossing into Pennsylvania.

Exposure of fluvio-glacial outwash in road cut on left.

Arrow Island Overlook on right.
Arrow Island Trail (Stop 4 on left).

Martinsburg outcrop on left, note low dip of slaty cleavage.

Cold Air Cave on left (Stop 3).

STOP 1. Point of Gap Overlook
Geologic Synopsis Structure, Stratigraphy, Geomorphology, Glacial Geology
The following questions are typically asked—or at least thought about—by laymen visitors to Delaware Water Gap:
What is a water gap?
What is the layering in the rocks?
What are the rocks made of?
Why are they of different colors?
Why are they tilted and curve in different directions?
Why is the cliff irregular and not smooth?
Why does the mountain top look flat from a distance?
Why did the Delaware River cut through the mountain here?
Did it cut through anywhere else?
Possible answers to these questions will be discussed with trip participants. But first, let us go through the jargon! The NPS has prepared a curriculum guide for school grades 3– 6, "The Many Faces of Delaware Water Gap" (Ferrence et al., 2003). In that guide, the Point of Gap Overlook is discussed (see Appendix 1), and the guide includes exercises in how the rocks formed, how the mountains were built, and glaciation.
Delaware Water Gap is often cited as the classic water gap in the Appalachian Mountains. Figure 6 portrays its geology. Anyone who studies the area is compelled to contemplate the history of the gap and why it is where it is. Is the structure seen in the gap (Fig. 2) as simple as it looks? What story do the satellitic folds in the Shawangunk tell? Why does the cleavage dip to the northwest within several hundred feet of the contact with the Shawangunk? These issues were summarized in the last GSA trip to this area four years ago (Epstein, 2006) and may be discussed at the stop.
The spectacular Delaware Water Gap has inspired people for generations, and created wonder on how this magnificent chasm through Kittatinny Mountain could have been cut by the Delaware River. Its story goes back in geologic time many hundreds of millions of years, although the actual cutting took place within the last few million years.
Our planet has had a dynamic history for much of its existence. Mountains have risen and fallen as continents have shifted and collided with each other during the earth’s more than 4.5 billion year history in a process called plate tectonics. Kittatinny Mountain is part of the Appalachian Mountain chain that extends for more than 2000 miles from Maine to Georgia. The birth of the Appalachians dates back several hundred million years. About 550 million years ago during the Cambrian period, a carbonate bank (A in top of Fig. 7) lying on the shelf of the old North American continental crust (B) faced eastward toward an ancient ocean, Iapetus (C). Africa lay across the Iapetus Ocean far to the east. A volcanic island (D) formed in the middle of the ocean as the African continent began to drift westward, beginning the closure of Iapetus. Thick sediments were deposited in the basin ahead of the volcanic island arc that were later consolidated into the Martinsburg Formation. As the ocean basin continued to close during continued plate convergence, sediments were deformed (middle figure) and later, not shown in Figure 7, uplifted ∼450 million years ago during the Ordovician period of geologic time, resulting in the buckling of the earth’s crust and uplifting of the ancient Appalachian Mountains. This period of mountain building is called the Taconic Orogeny. Sands and pebbles from the rising mountains were shed to the northwest during Silurian time, deposited across the warps and folds in the underlying Martinsburg. These clastic rocks were to become the Shawangunk Formation that holds up the mountain at the gap. Other orogenies variously affected the rocks in the Delaware Water Gap area. During the Devonian period, the Acadian orogeny uplifted mountains to the southeast which resulted in deposition of thick sediments seen in the Pocono Mountains today, but it had little or no structural effects on the rocks here. The Alleghenian orogeny at the end of the Paleozoic era, probably beginning in the Pennsylvanian period, folded and faulted all the rocks in eastern Pennsylvania, and was responsible for the folds seen in the Gap. It was at this time that Africa finally collided with North America.
For many millions of years erosion has worn down these rocks–the harder rocks stand as mountains while the softer rocks were eroded to form valleys. The sandstones and conglomerates of the Shawangunk Formation (shown by the stippled pattern in Figure 7) are among the hardest rocks in the entire Appalachian Mountains and form some of the highest ridges, extending all the way south to Alabama.
How the Gap was Formed
Some millions of years ago, the headwaters of a southeastward flowing river that was still south and east of here (perhaps near present-day Trenton, New Jersey) eroded backward toward the Kittatinny Ridge (A in lower Fig. 7). The hard rocks of Kittatinny Mountain presented an obstacle to erosion, and the Delaware found a place in the ridge where the rocks are more highly fractured and less resistant to the erosive power of the river. Thus, the river eventually worked its way headward through the mountain (A), ―capturing‖ waters on the other side (B) and establishing the present course of the Delaware through Kittatinny Mountain (C). It carved it way through the rocks that make up the Pocono Mountains to the north. Carrying sand and pebbles, which eventually wind up in the Atlantic Ocean, the Delaware River continues to downcut and widen what was originally a small cleft in the rock. That cleft, over time, has been enlarged into today’s mile-wide chasm: The Delaware Water Gap.
At this stop we may discuss the several intricacies of structural geology in this area, such as origin of slaty cleavage, pressure-shadow mechanism affecting cleavage, and ages of deformation. Maybe not!

Contact between the Shawangunk and Bloomsburg
Contact between the Shawangunk and Bloomsburg dipping 35°NW.

Southeast-dipping rocks in the Bloomsburg Red Beds.
US 611 traverses the Bloomsburg for the next 0.8 miles in a series of small undulating, low-amplitude folds. Note the southeast-dipping cleavage.

Crest of the Cherry Valley anticline
Crest of the Cherry Valley anticline in the Shawangunk Formation at top of road. The contact between the Shawangunk Formation and Bloomsburg Red Beds is conventionally placed at the base of the lowest red bed. However, at this locality this color change migrates up and down section by as much as 700 feet, making for a peculiar map pattern (Epstein, 1973). Enter upstream side of Delaware Water Gap.

Northwest-dipping rocks of the Shawangunk Formation on left.

STOP 2. Lake Lenape
We will follow the Appalachian Trail along an abandoned blacktop road that once led to the top of Mount Minsi to a fire tower. At the north edge of the pond is a memorial to Sean Dolan, A Delaware Water Gap fire fighter who died in a nearby car accident in 2004.
Lake Lenape is near the trough of one of many small folds in Delaware Water Gap (Fig. 8). It is in an area where the contact between the Shawangunk Formation and Bloomsburg Red Beds is based on change from gray in the Shawangunk to reddish in the Bloomsburg. In this immediate area, this color change variably cuts across ∼700 feet of stratigraphic thickness, making for the complex boundary seen on the map.
Lake Lenape is a marvelous area to give students an opportunity to examine several rock types, including sandstones, siltstones, and shales, to determine differences between bedding and rock cleavage, and to make a crude clinometer to prepare a map of the local gentle syncline.
The curriculum guide handout (Appendix 2) will provide instructions on how to use a compass, prepare grain size charts in order to determine sedimentary rock type, and encourage students to examine the local biota. Be wary of poison ivy, which covers the southernmost outcrop that will be measured. Here, have the students eyeball the dip with the clinometer rather than placing it on the rock. There is also an exercise that asks the geologic question, "How Do Lakes Form?"
"The Many Faces of Delaware Water Gap" is a 125-page geology curriculum (grades 3– 6) available from the Delaware Water Gap National Recreation Area. It includes field trips for five locations in the park in Pennsylvania and New Jersey, as well as a 20-page introduction to general geologic topics for the park. Teachers are invited to contact the park for a copy
An interesting exercise would be to have the students walk from the lowest point along the road for a little more than 100 feet up the trail to the south where the outlet is located, ∼4 feet higher in altitude. Then ask them these questions: Why is the outlet not at the lowest point along the road? Did the lake formerly drain at the lowest point? (Have them look to the east of the road to determine where the most gully erosion occurred.)
Point out the location of rhododendrons–on the north slopes in the shade and on acid, organic-rich soil.
There is a splendid overlook and view of the Delaware Water Gap by following the Appalachian trail for a short distance where the trail leaves the road ∼600 feet south of the pond (see Fig. 8). From here you can discuss some of the folds in the Bloomsburg Red Beds across the river.

STOP 3. Cold Air Cave
This talus cave (Fig. 9A) was formed by juxtaposed alignment of large talus boulders derived from conglomerate and sandstone blocks of the Shawangunk Formation above. Some of these blocks are nearly 30 feet long. A large talus floe overlies the cave (Fig. 9B) and a large cleft in the cliff above (Fig. 9C) confirms the potential for generating these blocks during periods of freeze and thaw. The cave may be as long as 70 feet, although only ∼30 feet of the cave is currently accessible to normal-sized individuals. According to Snyder (1989), the cave was discovered ca. 1870 when very cold temperatures, approaching 30 °F, were reported coming from the opening. The cave became an attraction sometime thereafter with a building erected at the entrance (Fig. 9D); tours given. Beginning in September 2000, a cooperative effort to understand the phenomenon of Cold Air Cave was undertaken by the U.S. Geological Survey and National Park Service. Readings for temperature, wind speed, wind direction, and weather conditions were recorded. The data indicates significant fluctuations in cave temperature; they are warmer in summer and cooler in winter. There are significant differences in temperature depending on whether the air is blowing into or out of the cave. Air blowing out is cooler than when it is blowing in the reverse direction, indicating that there is storage of cold air in the scree system and possibly the bedrock above. The average temperature in the parking lot is only slightly cooler than underground temperatures found at this latitude—normal is 54–56 °F. The average temperature in the cave is surprising, however, and was unexpected. In conclusion, Cold Air Cave continues to attract and mystify people with its local folklore, blowing cold air, and mysterious scientific explanation.
NOTE: Since the time of the preparation for this stop, this cave and others throughout DEWA, have been closed to the public because of a virulent fungus, "white nose syndrome", that threatens the local bat population (http://www.nps.gov/dewa/parknews/upload/newsBATCAVES.pdf).

Small outcrop in the Martinsburg Formation on right
Small outcrop in the Martinsburg Formation on right (Figure 10). Note the gently northwest-dipping (5°) cleavage due to fanning in a pressure shadow of the syncline defined by the Shawangunk Formation that will be discussed at Stop 1. Bedding here dips 25° NW.

STOP 4. Arrow Island Overlook and Trail.
Arrow Island, a streamlined bar, is presently being modified by the Delaware River. This occurs due to a decrease in the velocity of the river as it emerges from the narrow confines of the gap to the north. Such a feature has been termed an expansion bar.
The trail is about one mile long (Figs 11 and 12), passing over glacial deposits and outcrops of slate and greywacke in the Martinsburg Formation, ending at a kettle hole pond near National Park Drive. There are several abandoned slate quarries and prospects along the trail, one of which we hope to visit.

Very coarse gravel in late Wisconsinan outwash terrace
Very coarse gravel in late Wisconsinan outwash terrace to right exceeds 80 feet in thickness. The gravel was either laid down between the valley's wall and stagnant ice forming a kame terrace, or it is the eroded remnant of a valley train that formerly filled the Delaware Valley.

Rock fence on right
Rock fence on right is composed of blocks of the Allentown Dolomite with abundant fine sedimentary structures.

Cross Slateford Creek.
In 1805, the Pennsylvania Slate Company developed a slate quarry south of the water gap near Slateford Creek. It is abandoned.

National Park Drive on right leads to Slateford Farm
An example of a National Historic Site maintained by the National Park Service.

Faulted and overturned beds in the Bushkill Member
Faulted and overturned beds in the Bushkill Member of the Martinsburg Formation in ravine to right.

Flat-lying slate in the Bushkill Member
Flat-lying slate in the Bushkill Member in a 100-foot-long abandoned quarry overlain by 10 feet of glacial drift in ravine to right. A dolomite concretion, characteristic of basal beds of the Martinsburg elsewhere, lies in the bottom of the quarry.

Crossing the concealed Portland fault
Crossing the concealed Portland fault, which juxtaposes Martinsburg against the Jacksonburg Limestone and rocks of the Beekmantown Group where it is exposed.

Enter Portland, Pennsylvania.

Cross Jacoby Creek
Deglaciation of the Jacoby Creek valley resulted in the formation of several proglacial lakes that became progressively lower as the ice retreated from the northeast-draining valley and lower lake outlets were uncovered (Ridge, 1983).

Allentown Dolomite crops out on right.

Cross the axis of the Ackerman anticline
Cross the axis of the Ackerman anticline (Drake and others, 1969) in the Allentown Dolomite approximately at point where ramp bears off to 1-80 West.

Coarse kame-terrace (outwash) deposits on right.

Unconformable contact - Martinsburg and Shawangunk
Unconformable contact (<5°, Beerbower, 1956) between the Martinsburg Formation (Ordovician) and Shawangunk Formation (Silurian) covered by talus on right. If you are quick, lucky, and can avoid a car crash, look up about 50 feet and see mudcracks in an overhanging shale in the Shawangunk. (Fig. 13).

STOP 5. Geologic Features Along the Red Dot-Blue Blazedunnfield Creek Trails
The Red Dot–Blue Blaze–Dunnfield Creek Trail circuit takes the hiker to the top of Mount Tammany in Kittatinny Mountain, New Jersey (Fig. 14), and in less than four miles, passes through many geologic phenomena, including a variety of rock types, landforms and glacial and structural features. The points of interest along the way (Fig. 15; Table 2), provide insight into these natural elements that influenced the formation, history and composition of Delaware Water Gap. Note that the sedimentary layers that make up the cliffs in the main part of the gap dip to the left, but in Dunnfield Creek valley to the left the beds are horizontal. Trip time is ∼4 hours.
Table 2. Localities of geologic interest along the Red Dot-Blue Dot- Dunnfield Creek trails at Stop 5.
1: Near contact between the Shawangunk Formation and Bloomsburg Red Beds.
2: Eight-foot-long boulder with slickensides.
3: Glacial kame terrace on silt, sand and gravel.
4: Glacial striae.
5: Rotted limestone glacial erratic.
6: Rib of Bloomsburg bedrock.
7: Series of greenish-gray and red siltstone, sandstone and shale of the Bloomsburg.
8: Large erratic, Schoharie Formation.
9: Overlook of the Delaware Water Gap.
10: Red sandstone and siltstone of the Bloomsburg have been polished by the last glacier (20,000 years ago), producing glacial striae.
11: Springs.
12: Beginning of Shawangunk Formation on steep slope.
13: Talus.
14: Rib of quartzite with joints.
15: Glacial cobbles and glacial striae on Shawangunk.
16: Gentle slope underlain by some shale.
17: Forest fire.
18: Overlook, many sedimentary structures in the Shawangunk.
19: Blue Blaze Trail descends slope through laurel and blueberries.
20: Exposure of Bloomsburg bedrock with glacial striae.
21: Soil erosion by boots and rain exposing Bloomsburg bedrock with glacial striae.
22: Erosion has removed about three feet of glacial till.
23: Dunnfield Creek falls over flat beds of the Bloomsburg in bottom of syncline.
24: Three large erratic boulders of slightly cherty limestone.
25: Intersection with Appalachian trail. Several more boulders in creek.
26: Plunge pool formed where the creek drops over hard sandstone and gouges out a rounded pool in softer shale below.
27: The creek erodes along a joint surface here forming a 30-foot sluiceway.
28: Large boulders fallen from adjacent Bloomsburg outcrop have sharp edges compared to the rounded and eroded edges of erratics.
29: Cleavage present in horizontal shale layers but not in sandstone. Erratic in creek.
30: Beginning of the terrace deposit that was first seen at locality 3.
31: 25-foot-long limestone erratic limestone.
32: Bridge. Flat alluvial fan towards parking lot made up of rounded cobbles.
33: Parking lot. Note 6-foot boulder 40 feet above the creek in terrace to right.
GLOSSARY
Alluvial fan: Gently sloping mass of sediment fanning out from a river mouth.
Cleavage: Closely spaced fractures along which a rock may split.
Erratic: A rock that was carried some distance by a glacier from its place of origin.
Kame terrace: Flat-topped hill formed from sediment that was deposited along a valley wall by streams that flowed from an adjacent melting glacier.
Slickensides: Polished and striated rock surface caused by one rock mass sliding past another.
Striae: Narrow parallel scratches cut into a rock surface by rock debris embedded inthe bottom of a moving glacier.
Syncline: U-shaped downfold of rock layers.
Talus: An apron of irregular rock fragments derived from and lying at the baseof a cliff.
Till: Unsorted mixture of clay, sand, and boulders deposited beneath a glacier.

Splendid folds in the Bloomsburg Redbeds
At the ramp turnoff from I-80 to Old Mine Road there are splendid folds in the Bloomsburg Redbeds showing the relations of cleavage and bedding (fig. 16). The southeast dip of cleavage in all limbs of the folds indicate that it was rotated by bedding slip after they formed.

STOP 6. Guide to the Geology of the Karamac Trail
The trail begins in the parking area at the traffic light and barrier along the Old Mine Road 400 feet north of the I-80 overpass (Fig. 17). This a level trail, nearly one mile long, along an old railroad grade, and along which a few different types of rocks (sandstone, shale, siltstone and conglomerate), two different geologic formations of Silurian age (Bloomsburg Red Beds and Shawangunk Formation), a landslide retained by a concrete structure (gabion), a few folds, joints, rock cleavage, and glacial boulders (erratics) can be seen. Terms in italics should be fully explained to students. The distance along the trail north from the parking area is shown in feet.
LOCALITY DESCRIPTION
-350 On the east side of the road is an excellent example of a small thrust fault and ramp in the Bloomsburg Red Beds (fig. 18). The floor of the thrust is at the base of a thick sandstone bed lying on top of shale and siltstone that are less resistant to erosion.
0 Parking area. Looking to the right up the steep slope are joints, the result of the tectonic stress that folded the rocks in the Delaware Water Gap area. Similar vertical fractures can be seen along the trail for the next 400 feet.
400 The smooth face in a 6-foot high bed of sandstone ahead is an excellent example of a joint (fig. 19). Note the cleavage in the silty beds at arrow.
500 The closely spaced fractures in some of the greenish and reddish beds are tilted into the hill in a much gentler angle than are the joints (fig. 20). This is cleavage which forms in shale and siltstone by reorientation of the mineral grains in the rock.
600 The interlaced segments of concrete is a 100-foot long gabion (fig. 21) which was constructed at this site to hold back a landslide that removed part of the Old Mine Road above the trail. Because of the slide the road is now a single lane with a three-minute traffic light to control traffic along this stretch, and it is unwise to walk along it. The concrete blocks are filled with cobbles to stabilize the road. Immediately above this site along the Old Mine Road there is the potential for another rockfall because blocks of rock are being separated along irregular joints (fig. 22).
1000 The islands in the middle of the Delaware River and terraces along its banks are made of sand that was deposited when the river flowed at a slightly higher level after retreat of the Wisconsinan glacier which left this area ∼20,000 years ago. The sand islands are mute testimony to a former higher level of the river.
1075 Rivulet tumbling down over dark red rocks. This is the Bloomsburg Red Beds. Note that the rock layers are nearly flat at this spot. These rocks were deposited by rivers flowing to the sea. The soft sediment, composed of mud and sand, was hardened or lithified into rock and the layers are termed bedding. The process of lithification results from a variety of causes, including cementation (the rock is cemented by minerals that precipitated out from ground water) and compaction (due to the weight of thousands of feet of overlying sediments that were deposited on top).
1300 Water emitting from a drain pipe. Just beyond a rivulet the bedding is tilted much more steeply to the south than previously (fig. 23), showing that rocks have been folded. The rocks here are no longer red, but shades of gray. Thus, we have left the Bloomsburg Red Beds and are into another rock unit, the Shawangunk Formation. It would be worthwhile to discuss the fact that the Bloomsburg overlies and is younger than the Shawangunk based on the dip of the beds here (law of superposition).
1800 This small anticline (fig. 24) interrupts the general south dipping layers along this stretch of the trail.
2000 Note that the bedding layers are tilted back towards the south, indicating that there is a syncline between here and the previously seen northward dipping beds. This is the site of a spring, where water, flowing through cracks in the underground rock (termed ground water), appears at the surface. During the summer when rainfall is less plentiful, the spring may dry up.
2400 Bedding in the Shawangunk Format ion dips (is tilted) gently to the south (fig. 25). Farther north along the trail and to the end of the trail it will be dipping northward, a structural configuration which is termed an upfold or anticline, named the Cherry Valley anticline because it is a major anticline that extends for several miles to the northeast and southwest. This outcrop is also a good example of crossbedding, which is defined by layers of rock that dip more steeply than the beds above and below and is caused by large ripples that formed in a rapidly moving stream during the Silurian Period.
3400 100-foot long outcrop through the Shawangunk Formation (fig. 26). A close look
at the different beds show that some have grains the size of sand (sandstone), in
others the grains are very fine (shale and siltstone), and some of the beds contain
pebbles, perhaps 0.5 inch long, in a rock termed conglomerate. The beds here are
tilted ∼20° toward the north.
4200 The gray rocks of the Shawangunk Formation here are more steeply dipping (33o) than to the south.
4500 So far all the loose boulders we have seen are quite angular in shape, having been derived by breaking off from the adjacent bedrock. Notice the large rounded boulders here. That shape implies that they have been water worn. But water needs to be very rapidly flowing to move boulders of that size. Because these rounded boulders are made up of a variety of rock types, some of which are foreign to the immediate neighborhood, it implies that they have been carried here by glaciers which invaded this area ∼20,000 years ago. Now, fortunately, the glaciers are gone. Could they return some time in our geologic future? This would be a good place to discuss climate change, both natural and anthropogenic. These boulders, because they have come from afar, perhaps several miles away, are termed erratics. In the ground underneath they are mixed with clay, a geologic deposit called till. Till forms much of the surface further northward along the trail.
4850 The rocks of the Shawangunk Formation are cut through here along this old railroad grade (fig.27). The beds are tilted more steeply than before; 62o at this spot. This is a good outcrop to show the different lithologies in the Shawangunk Formation and the cleavage in the shales that dip 85o northwest. It is also a good outcrop to illustrate the various orientations of joints. It would also be an excellent locality to demonstrate the use of a Brunton compass to acquire structural orientations and also to demonstrate the orientation of cleavage in folds (fig. 28) and also to discuss the relationship of cleavage to overturned beds in a fold.
4950 Trail ends at bridge abutment, part of the Lackawanna Railroad bridge that was removed during the flood of 1955 (Fig. 29). Excellent blocks of conglomerate at the abutment.

2: GLACIAL GEOLOGY AND GEOMORPHOLOGY OF THE PASSAIC, HACKENSACK, AND LOWER HUDSON VALLEYS, NEW JERSEY AND NEW YORK
Scott D. Stanford
New Jersey Geological Survey
P.O. Box 427
Trenton, NJ 08628
Scott.Stanford@dep.state.nj.us
Introduction
The New York City area is a gateway between glaciated terrain to the north and preglacial terrain and the Atlantic Ocean to the south. The Hudson valley is one of the three principal conduits into the Atlantic for meltwater draining from interior North America. Meltwater and sediment discharges from the Hudson have been invoked as the source of glaciogenic deposits and erosional features on the New Jersey continental shelf. Freshwater outflows from glacial lakes in the Ontario basin discharged down the Hudson during the late Wisconsinan deglaciation. Those outflows may have triggered the Younger Dryas and earlier climate coolings by suppressing ocean circulation in the North Atlantic (Donnelly and others, 2005; Rayburn and others, 2007; Obbink and others, 2010). More locally, glacial deposits are productive aquifers in places. Their strength properties and permeability are important features to consider when engineering infrastructure and foundations, modeling groundwater flow, and remediating groundwater and soil contamination.
Deposits of at least three glaciations are present in the New York City area. The earliest glaciation, known as the pre-Illinoian, may have occurred in the late Pliocene, between 2 and 2.5 Ma. A second glaciation is likely of late Illinoian age (∼150 ka, oxygen-isotope stage 6), although it may be somewhat older. For ease of reference, it will be referred to as the Illinoian glaciation in this paper, although an Illinoian age is not proven. The most recent glaciation is of late Wisconsinan age and reached its maximum position, as dated by radiocarbon, between 21 and 20 ka (all dates related to the late Wisconsinan glaciation are stated in radiocarbon years). Fluvial deposits south of the glacial limit, and fluvial erosional features preserved within glaciated terrain, provide evidence for preglacial and interglacial routes of the Hudson and its tributaries. This paper will survey the geomorphic and glacial history of the lower Hudson, Hackensack, and Passaic valleys in northeastern New Jersey and adjacent New York, and will discuss lake-drainage events in the upper Hudson valley that affected the lower valley and shelf during the late Wisconsinan deglaciation. A final section will discuss the glacial stratigraphy of the buried valley aquifer system in the upper Passaic basin.
The observations presented here are based on surficial geologic mapping at 1:100,000 scale in New Jersey conducted in the 1980s and early 1990s as part of a cooperative mapping program by the N. J. Geological Survey and the U. S. Geological Survey (Stone and others, 2002), and subsequent 1:24,000 quadrangle mapping by the NJGS in the 1990s and 2000s conducted in part with funding from the Statemap component of the National Cooperative Geologic Mapping Program, administered by the USGS. All of the quadrangles covering the New Jersey part of the study area have been mapped and published (pdfs for all maps can be viewed and downloaded at (http://www.njgeology.org/pricelst/geolmapquad.htm). These mapping efforts built on the excellent early work of R. D. Salisbury, C. E. Peet, and H. B Kummel (in Salisbury, 1895, 1902; Merrill and others, 1902; Bayley and others, 1914). Observations in New York also draw from mapping by Woodworth (1901) and Fuller (1914) on Long Island, followed by subsurface mapping conducted as part of groundwater-resource investigations in Brooklyn and Queens (Perlmutter and Geraghty, 1963; Soren, 1978; Buxton and Shernoff, 1999), and the regional map compilation of Cadwell (1989). Lacustrine and fluvial features in the upper Hudson valley discussed in the section on Lake Albany were compiled by Stanford (2010) from the works listed in the caption for fig. 6.

: GLACIAL GEOLOGY AND GEOMORPHOLOGY OF THE PASSAIC, HACKENSACK, AND LOWER HUDSON VALLEYS, NEW JERSEY AND NEW YORK

STOP 1. The Narrows
Walk up park paths over knoll and ridge topography of the terminal moraine to the viewpoint at the bluff top of the Narrows and Verrazano Bridge.
We are standing on the late Wisconsinan terminal moraine, a 1 to 2 mile-wide (1.6 to 3 km) belt of till between 50 and 150 feet (15 and 45 m) thick, with up to 100 feet (30 m) of ridge, knoll, and basin surface relief. Ice arrived at the moraine just after 21 ka (all dates stated in radiocarbon years), and varves counted in the southern basin of Lake Passaic indicate that the ice front stayed in the moraine belt for about 750 years (Reimer, 1984). The height of the headlands here and in Brooklyn indicates that the moraine was once continuous across the mile width of the Narrows at about 50 feet (15 m) in elevation. During late Wisconsinan retreat the Narrows dam and a moraine dam across the Arthur Kill at Perth Amboy, NJ held in glacial Lake Bayonne in the Arthur Kill-Kill van Kull-New York Bay lowland. Lake Bayonne was controlled by an eroding spillway on till at the Perth Amboy dam, and gradually lowered a total of about 50 feet (15 m) as ice retreated. When the retreating ice margin uncovered Hell Gate in the East River (M1 on fig. 3), Lake Bayonne drained eastward into the Long Island Sound lowland and Hell Gate became the outlet for Lake Albany. The Hell Gate spillway is on gneiss at ∼730 feet (&sim9 m). The Hell Gate stage of Lake Albany was thus a stable lake and the shoreline, reconstructed from ice-contact deltas (text fig 6), projects to the Narrows at &sim70 feet (&sim21 m), indicating about 120 feet (36 m) of freeboard on the Narrows dam during the Hell Gate stage. The Hell Gate stage expanded northward up the Hudson valley to north of the Highlands, where delta elevations record the onset of an unstable phase of Lake Albany, with declining lake levels recording an eroding spillway (fig. 6). This indicates breaching of the Narrows dam and replacement of the stable Hell Gate spillway with an eroding spillway on moraine till. Dam breaching was caused by an outburst flood at 15.5 ka from the Augusta stage of Lake Wallkill into Lake Albany. When the north end of Schunnemunk Mountain (and Storm King in the Hudson valley) was deglaciated, the Augusta stage lowered 230 feet (70 m), releasing 6 mi³ (25 km³) of water into Lake Albany. About 40% of this volume was probably added suddenly, producing a rapid rise in Lake Albany of about 160 feet (49 m), sufficient to overtop the Narrows dam.
Dam breaching also initiated fluvial erosion of the Hudson shelf valley, which leads from the Narrows to the edge of the continental shelf. The shelf valley was subaerially exposed until about 12 ka, providing 3500 years for fluvial incision of this prominent feature.
The moraine served as the spillway for Lake Albany until ice had retreated upvalley to just south of the Albany area, where delta elevations indicate that the spillway had shifted onto the emerging lake bottom in the Newburgh area, about 60 miles (100 km) up the valley from the Narrows. During its operation, the spillway on the moraine had eroded the dam to an elevation of -200 feet (-60 m). This depth allowed the rising sea to enter the Hudson valley at about 12 ka. From 12 to 10 ka high relative sea level in the lower Hudson valley limited fluvial incision of the lake bottom in the upper valley, providing quasi-stable spillways for the Quaker Springs and Coveville stage of Lake Albany, and the upper Fort Ann stage of Lake Vermont (fig. 6).
Major lake outflows from the Ontario basin discharged down the Mohawk valley and into the Hudson during the Erie Interstade between 14.5 and 14.2 ka, when the Mohawk valley was briefly deglaciated (Ridge, 1997), and again from 12.7 to 11 ka when the Mohawk valley was the outlet for Lake Iroquois (Wall and LaFleur, 1994). These outflows exited to the shelf through the Narrows and contributed to its erosion. When the Covey Hill threshold north of the Adirondacks was deglaciated, Lake Iroquois dropped in two stages to the lower Fort Ann level of Lake Vermont in the Champlain lowland, releasing 170 mi³ (700 km³) and 600 mi³ (2500 km³) of water at 10.9 ka (Rayburn and others, 2005). These megafloods also exited through the Narrows, and may have triggered the Younger Dryas stadial in the North Atlantic region between 10 and 11 ka. They were the last glacial events to affect the Hudson valley.

Serpentinite outcrop to left in roadcut.

Salt marsh along Arthur Kill visible to right.
This is the floor of Lake Bayonne.

Enter Fresh Kills landfill, cells on both sides of 440.
Former offload dock for garbage barges to right at bridge over Fresh Kills tidal creek. Landfill now closed and garbage is exported by truck and train.

Climb onto an upland on Cretaceous deposits, veneered with till.

STOP 2. Red Bank Bluffs, Mount Loretto State Unique Area
NO SHOVELS, PICKS, OR HAMMERS
This stop requires a 1.25 mile walk along a beach and the possible fording of a shallow (ankle-deep) tidal creek. If you do not wish to do this, please remain on the bus, which will proceed 0.5 mile down Hylan Blvd. to meet us at Lemon Creek Park, at the end of the beach walk.
Walk south on driveway from parking area across the terminal moraine (fig. 9) to the beach on Raritan Bay, then walk northeastward along the beach to the parking lot for Lemon Creek Park, viewing bluff exposures along the way.
These bluffs provide an excellent exposure of the till that forms the terminal moraine. The bluffs were formed by wave erosion that has cut back about 1000 feet (300 m) into the outer edge of the moraine (fig. 9), which is estimated by fitting a smooth curve to the front of the moraine where it comes ashore to the north on Staten Island and to the west in New Jersey. The till exposed here is a compact, reddishbrown silty fine sand to silty fine-to-medium sand, containing 5-15% by volume pebbles and cobbles, and very few boulders. Pebble composition, counted on a total of 622 pebbles aggregated from five sites in the till along the bluff, is 54% red siltstone, 23% white to yellow well-rounded quartz pebbles, 13% gray siltstone and sandstone, 7% gneiss, 1% chert, and 1% purple conglomerate. The red siltstone is from the Passaic Formation in the Newark Basin. The quartz pebbles are from the Pensauken Formation, a Pliocene fluvial gravel that was widespread in the New York City area before glaciation and is locally preserved in erosional remnants beneath till on Staten Island and in adjacent New Jersey. The gray siltstone and sandstone are from gray beds in the Newark Basin and from Paleozoic sedimentary rock in the Green Pond outlier and Wallkill valley. The gneiss is from Proterozoic bedrock in the Hudson Highlands. The chert is from Paleozoic carbonate rock in the Wallkill valley. The purple conglomerate is from the Green Pond and Skunnemunk formations in the Green Pond outlier, although some may be from Newark Basin fanglomerates. The reddish matrix color is derived from erosion of the red siltstone and sandstone of the Newark Basin. Notably absent or rare are basalt, diabase, and serpentinite, all local bedrock types found within 5 to 20 miles of the bluffs. Glacial flowlines, however, show that ice moving down the Hackensack lowland to this location did not cross those lithologies (fig. 2).
Also observed in the bluff (locations 2 and 4, fig. 9) are lenses or blocks of thinly bedded white and gray silt, fine sand, and coarse sand. The lenses at location 4 are within a deformed body of glaciofluvial sand and gravel, the one at location 2 appears to be within till, although it is situated behind an old sea wall and may have been artificially emplaced. These are glacially thrust blocks of Cretaceous sand and silt of the Magothy Formation, which, along with the underlying Raritan Formation, onlaps the bedrock in the southern half of Staten island and directly underlies the till. The undeformed bedding in the thrust blocks perhaps indicates that they were frozen when glacially entrained.
The 70-foot hill is cored with light gray to pinkish-gray to very pale brown, cross bedded, clean sand and pebble-to-small cobble gravel, overlain by till. Dips on the cross-bed sets are oversteepened in places (location 3), and recumbent fold axes are also visible on the bluff face in some of the finer-grained beds, indicating that the sand and gravel has been deformed. This gravel is proglacial glaciofluvial outwash that was overrun and deformed by the advancing glacier. The deformation thickened the gravel here to form the core of the hill. Glaciofluvial plains front the moraine when it comes ashore further north on Staten Island, on Long Island, and at Perth Amboy, New Jersey. This deposit is of similar origin. Pebble composition in this unit, counted on a total of 366 pebbles aggregated from three sites in the exposure, is 41% red siltstone, 41% quartz pebbles, 13% gray siltstone and sandstone, 4% gneiss, and 1% purple conglomerate. The greater quartz-pebble content in the gravel compared to the till is from meltwater reworking of Pensauken Formation gravel that was likely widespread on the land surface in front of advancing ice.
Lenses of laminated silt and sand occur within the till at several places (locations 1 and 5). These lenses are about 20 to 50 feet long and generally less than 5 feet thick. They are approximately the same dimensions as the shallow basins on the moraine surface (visible in the meadows on the walk in) and may be swale-pond fills on the moraine surface that were later overrun by readvances as the ice front moved back and forth in the moraine belt. Again, lack of deformation suggests the fills were frozen when overrun.

Cross Mill Creek, here a tidal creek.
The head of this valley to the east (right) was an early spillway for Lake Bayonne, before it shifted to the moraine dam at Perth Amboy.

Cross the Arthur Kill.
Railroad bridge to right is the Arthur Kill lift bridge, longest center-lift bridge in the world. It was built by the B&O railroad in 1959. Piers for it and the Goethals Bridge are on red shale at a depth of 30 to 40 feet.

Bayway refinery on left.

Newark Airport to left, Port Newark to right.
Both are built on former salt marsh atop Lake Bayonne lake-bottom clays.

Rise from lake bottom onto a till on sandstone upland.

Roadcut in Orange Mountain basalt, of Lower Jurassic age.
This basalt holds up First Watchung Mountain.

Roadcut through terminal moraine (behind soundwalls).

Roadcut on right in Preakness basalt
Roadcut on right in Preakness basalt, holding up Second Watchung Mountain.

Cross Chatham-stage sluiceway
Cross Chatham-stage sluiceway, occupied by a man-made lake here.

STOP 3. Watchung Reservation. Lunch and Pre-Illinoian Till.
NO SHOVELS OR PICKS
Before lunch at the picnic area, walk down trail towards Tracy Drive to the head of a gully with a rock-gabion floor, descend the gully to view exposures of till, then exit left at bottom of gully and return uphill on adjoining gravel trail to the picnic area.
This gully is eroded into the easternmost deposit of pre-Illinoian till in New Jersey. This deposit is on the gentle dip slope of First Watchung Mountain, just outside the late Wisconsinan limit. Late Wisconsinan till (Qr on fig. 10), laid down by a brief advance beyond the terminal moraine, onlaps and overprints the pre-Illinoian till just to the north. The pre-Illinoian till here is a reddish-brown to reddishyellow sandy clayey silt with deeply weathered to saprolitized pebbles and cobbles of red and gray siltstone, basalt, and gneiss. Gray quartzite, purple quartzite-conglomerate, black to brown chert, and well-rounded white to yellow quartz pebbles are unweathered. Large cobbles and boulders of gneiss are also intact, perhaps because the outermost weathered parts have spalled off. Fresh exposures observed in 1991 showed a thin tongue of late Wisconsinan till with lightly weathered to unweathered siltstone, gneiss, and basalt clasts overlying weathered micaceous siltstone of the Feltville Formation, at the downstream end of the gully. These materials are no longer well exposed here but can be seen in cuts along the valley side to the south. These observations show that the pre-Illinoian till rests on a gently sloping bedrock bench about 30 feet above the valley floor.
This landscape position is somewhat anomalous for pre-Illinoian till. Generally it is preserved only on flat surfaces on divides or hilltops. The anomaly is explained by the unusual history of this valley. The Blue Brook valley was deepened and widened around 21 ka because it served as the sluiceway (dotted line on fig. 10) for the Chatham stage of Lake Passaic (fig. 7). Before this incision, bedrocksurface elevation contours (Stanford, 1991) indicate that this was a broad divide in the intermontane valley between First and Second mountains, with a much smaller Blue Brook draining southwestward from the divide and another small stream draining northeastward in a valley now buried by the terminal moraine and a small fronting outwash plain. The divide area was protected from erosion, preserving the pre-Illinoian till. The valley here is thus only 21,000 years old, not >800,000 years old like the other valleys in the pre-Illinoian glacial terrain. When the Hackensack lobe of the late Wisconsinan glacier blocked the Short Hills gap, the Blue Brook spillway shut down and the ice front here, no longer held at bay by the rushing lake outflow, briefly advanced into the now-empty sluice, depositing the thin tongue of till observed within the channel.

Climb up terminal moraine plugging the former Short Hills gap.

Crest of moraine in Short Hills gap.
Enter Lake Passaic basin.

Cross Passaic River, on floor of Lake Passaic.

Roadcuts for the next half mile are in lacustrine-fan deposits
Roadcuts for the next half mile are in lacustrine-fan deposits laid down in Moggy Hollow stage of Lake Passaic.

Black Meadows marsh to right, on floor of Lake Passaic.
Terminal moraine forms rise in front. Training facility for NY [sic] Jets football team to left.

Roadcut through moraine.
Roadcut through moraine. Till of the moraine hereabouts caps a section of stacked Illinoian and late Wisconsinan lacustrine sediment about 350 feet thick, one of the thickest glacial sections in NJ.

Cross under I-80.
Buried pre-intermediate Passaic-Rockaway valley here, filled with 200 feet of stacked late Wisconsinan and Illinoian till and lacustrine deposits.

Cross Rockaway River
Cross Rockaway River, redirected in postglacial time from the valley at 79.7.

Top of Boonton delta
Top of Boonton delta, deposited in Moggy Hollow stage of Lake Passaic.

Roadcut in another Moggy Hollow stage delta
Roadcut in another Moggy Hollow stage delta at Brook Valley Road overpass.

Outcrops of gneiss on left along Highland Front.

Roadcut in yet another Moggy Hollow stage delta
Roadcut in yet another Moggy Hollow stage delta, to be discussed at Stop 4.

STOP 4. Lake Passaic Fan-Delta Complex, Foothill Park, Pequannock
Walk from parking lot to the southwest corner of the park lawn, near wall of former gravel pit, to the left of the striated gneiss outcrop. When returning to parking lot, visit the outcrop, which is interlayered white, buff, and light green quartz-plagioclase gneiss and dark gray amphibolite of Middle Proterozoic age. The gneiss and amphibolite show ductile deformation and mylonitic fabric because this outcrop is very close to the Ramapo Fault, the bounding normal fault on the west edge of the Newark Basin (Volkert, 2010).
Foothill Park and the office complex to the east over to NJ 23 are within a former gravel pit. This pit was dug into a lacustrine fan deposited in the Moggy Hollow stage of Lake Passaic. The fan formerly rose as much as 50 feet above the present land surface. The excavated part of the fan is the top of a deposit more than 200 feet thick (fig. 11, section AA’), extending down to a thin basal layer of till resting on bedrock. The pit exposures, and logs of test and production wells adjacent to and within the former pit, show that the fan is pebble-to-cobble gravel and sand with some interbeds of finer sediment, for its entire thickness.
Pebble composition of the fan gravel, counted on a total of 737 pebbles aggregated from 5 sites in the former pit, is 64% gneiss, 31% gray sandstone and siltstone, and 5% purple conglomerate. Gneiss is from the Highlands, adjacent to the deposit to the north and west. Gray sandstone and siltstone are from Paleozoic rock in the Wallkill valley and Green Pond outlier to the north. Purple conglomerate is from the Green Pond outlier. Notable is the absence of red siltstone and basalt from the Newark basin, which underlies most of the fan complex and the broad lowland to the east. Ice flow during glacial advance here, as recorded by striations in the vicinity (fig. 11), including those on the outcrop in the park, was southward from the Highlands into the Newark Basin. Most ice flow from the Highlands into the Newark Basin was blocked by earlier-arriving ice of the Passaic lobe flowing southwesterly in the Basin (fig. 2), so the pattern here is somewhat anomalous. We are near the mouth of the broad, deep, south-trending Wanaque River valley that cuts the Highlands just to the north. This valley helped channel Highlands ice out into the Newark Basin in this area. The Highlands ice deposited gneiss-rich till (Netcong Till, Qn on fig. 11) on the red siltstone bedrock hereabouts. This till also contains significant amounts of gray siltstone and purple conglomerate. Subglacial meltwater feeding the fan complex during deglaciation eroded this till, and gneiss bedrock just to the north in the Wanaque valley, rather than the local red siltstone, accounting for the Highlands provenance of the fan gravel.
The northwest edge of the pit was dug into a small Moggy Hollow stage delta. This delta is now largely gutted by the I-287 cut and fill (at mile 89.9 of road log) but a fragment west of I-287 marks its original surface at about 420 feet (128 m) in elevation, indicating that Lake Passaic here was about 500 feet (152 m) deep before deposition of recessional lacustrine deposits (fig. 11, section AA’). The north wall of the pit is dug into a Great Notch stage delta with a top surface at 320 feet (97 m), visible as the treeline on the hill across the park to the north. The pit wall here shows delta foreset sand overlying pebble-to-cobble fan gravel, indicating that the delta prograded over the older fan deposit. Fan deposits laid down in the Moggy Hollow stage also crop out north of the delta (fig. 11), indicating that this delta was not deposited in contact with the glacier. Rather, as the ice front retreated northward from the fan complex toward the present position of NJ 23, an outlet channel for Lake Butler, a local lake that occupied a north-draining valley just to the west of, and higher than, Lake Passaic, was opened at the 500- foot (152 m) elevation on the hill to the west of the fan complex (arrowed line on fig. 11). At the same time, Hackensack lobe ice on the east side of the Lake Passaic basin uncovered Great Notch, and Lake Passaic lowered 80 feet (24 m) from the Moggy Hollow to the Great Notch stage. This allowed the Butler outflow to erode the north end of the Moggy Hollow delta and adjoining fans and redeposit the sediment in the Great Notch stage delta. These relationships fix the geometry of ice margin M1 (fig. 3) between Great Notch and the Highlands.
The thick, permeable fan deposits here are a prolific aquifer. Production wells for Pequannock Township (circled dots on fig. 11) are screened between 120 and 200 feet (37 and 61 m) in depth and, when first drilled, yielded between 700 and 800 gpm. The fan deposits here comprise the full thickness of the valley fill and so are unconfined, but fan gravels are more commonly buried, and confined, by lake clays (Qpml on fig. 11). Such buried, confined fan gravels are the principal valley-fill aquifers in New Jersey.

Flat plain here is top of a broad shallow-water delta
Flat plain here is top of a broad shallow-water delta deposited in the Totowa stage of Lake Passaic (fig. 7). Late Wisconsinan overdeepening in this area extends to more than 100 feet (30 m) below sea level; the overdeepening is filled with up to 300 feet (91 m) of recessional lacustrine deposits.

Climb from delta onto till hill.

Descend onto a stream terrace
Descend onto a stream terrace deposited in the Totowa stage, on top of lake clay.

Roadcut through Great Notch-stage lacustrine fan
Roadcut through Great Notch-stage lacustrine fan which was the dam for the Totowa stage.

Cross Passaic River
Cross Passaic River, much larger than before because it now includes the Pompton River.

STOP 5. Preglacial Drainage, Paterson Gap Overlook, Garrett Mountain Reservation
The Paterson gap in First Watchung Mountain is one of six paired wind gaps through the three Watchung ridges that, together with Sparkill gap in the Palisades ridge to the northeast (visible on the horizon from the overlook), define the preglacial route of the Hudson River in the Pliocene (fig. 1). These gaps are all between 1 and 1.5 mile (2 and 3 km) wide and have preglacial rock floors that decline evenly from 230 feet (70 m) at Sparkill to 180 feet (55 m) at Millburn, the southernmost gap. These rock-floor elevations are on grade with the Pensauken plain, tying them into a dated depositional chronology. This chronology indicates that, in the Pliocene before the pre-Illinoian glaciation, the Hudson was a tributary to the trunk Pensauken River that flowed southwesterly along the inner edge of the Coastal Plain, and discharged to the Atlantic across what is now the Delmarva Peninsula (fig. 1). The pre-Illinoian glacier diverted the Hudson and the Pensauken rivers to the Atlantic across western Long Island, and the gaps were abandoned. After the diversion, in the early and middle Pleistocene, the Passaic established a course that exited the Watchung crescent via the Short Hills and Millburn gaps (fig. 8A). The Illinoian glacier filled the Short Hills gap with till to a height sufficient to divert the Passaic northward through the Little Falls and Paterson gaps, which were not filled, in post-Illinoian time. The Passaic reestablished this route after the late Wisconsinan glaciation, which had further filled the Short Hills gap. Passaic Falls, a 77-foot drop over basalt in the center of Paterson, formed after the late Wisconsinan deglaciation as the river reestablished its course across a new escarpment between the resistant basalt floor of the wind gap and a glacially scoured siltstone lowland to the east. Hydropower from the falls was the original source of industrial development in Paterson, starting in 1791 with the "Society for the Establishment of Useful Manufactures" founded by Alexander Hamilton, which was one of the earliest industrial developments in the United States. The original design of water-power canals and city streets was by Pierre L’Enfant, who also designed the layout of Washington, D. C. Electricity is still generated at the falls.

Area of the Great Notch spillway, now defaced by road and railroad cuts.

Cross sluiceway
Cross sluiceway eroded by drainage of Great Notch stage around Garrett Mountain.

Descend onto flat surface of delta
Descend onto flat surface of delta deposited in Lake Delawanna, a local lake held in by a sediment dam in the lower Passaic valley.

Cross Passaic River, tidally influenced here.

Roadcuts here are in a till on sandstone upland.

Descend to the Meadowlands salt marsh
Descend to the Meadowlands salt marsh, on the floor of Lake Hackensack. A narrow, glacially overdeepened trough extending to more than 300 feet (90 m) below sea level runs along the west edge of the Meadowlands and is filled with lacustrine fan deposits overlain by lake clay.

Cross Berrys Creek, move right for exit to NJ Turnpike.
Giants Stadium on left, home to the NY [sic] Giants and NY [sic] Jets, and site of the 2014 Super Bowl.

View of Snake Hill, a diabase intrusion into siltstone
View of Snake Hill, a diabase intrusion into siltstone, to left, and landfill mountains to right, resting on salt marsh atop Lake Hackensack clays.

Cross Passaic River.
Newark to right, Pulaski Skyway to left.

Cross under Pulaski Skyway, completed in 1932.
Depth to shale bedrock ranges from 30 to 130 feet along the 4-mile length of the viaduct. Lake clay overlies the bedrock.

3: THE TIMING, LAYERING, COMAGMATIC BASALT FLOWS, GRANOPHYRES, TRONDHJEMITES, AND MAGMA SOURCE OF THE PALISADES INTRUSIVE SYSTEM
John H. Puffer
Department of Earth & Environmental Sciences
Rutgers University
Newark, New Jersey, 07102
Jeffrey C. Steiner and Karin A. Block
Department of Earth and Atmospheric Sciences
City College of New York
138th and Convent Avenue,
New York City, New York 10031.
Alan Benimoff
Department of Engineering Science and Physics
College of Staten Island
2800 Victory Boulevard,
Staten Island, NY 10314
Abstract
Our understanding of the Palisades is currently undergoing considerable revision. New radiometric data is being accumulated showing that the duration of Palisades intrusive activity is much greater than previously estimated. Active research issues include: In-situ fractionation vs. multiple intrusion of pre-fractionated magma pulses; correlation of Palisades layers with Watchung basalt flows; the origin of the olivine layer; and the role of contamination vs. fractionation in the development of the Sandwich Horizon, granophyres, trondhjemites, and syenite bodies within the sill. We will examine evidence pertaining to each of these issues at field trip stops between Staten Island and Nyack Beach State Park.
Preliminary unpublished evidence gathered at these sites and elsewhere indicates that the Palisades was intruded over a prolonged time span by multiple pulses of magma that were variously prefractionated at depth. Each pulse underwent limited additional fractionation after emplacement. According to recently published work and unpublished mineralogical evidence, the lower Palisades consists of several layers that correlate with individual Orange Mountain basalt flows while each of several upper Palisades layers correlate with Preakness basalt flows. Recently published geochemical evidence also indicates that trondhjemite dikes and syenite veins near the base of the sill are products of country-rock fusion. In contrast, preliminary unpublished evidence suggests that the siliceous Sandwich Horizon and granophyres layers at central and upper sill positions are the product of complex processes including fractionation. Finally, most geologic evidence supports a Palisades magma source related to decompression -melting triggered by Pangean crustal thinning and rifting along previous plate sutures located over subduction enriched mantle.
Introduction
The Palisades sill has been the subject of considerable geologic literature. Up until the last few years it has generally been thought of as a composite intrusion consisting of an initial thin intrusion followed by a much thicker intrusion of similar composition that underwent considerable in-situ fractionation. Recent and ongoing research has modified this simplistic fractionation model for the Palisades that is presented in many petrology text-books and is making progress toward several additional new or unresolved issues including:
1) Geochronology - the unresolved timing of the intrusion and extrusion of Palisades magma based on the latest geocronological techniques;
2) In-situ fractionation vs. multiple intrusion of pre-fractionated magma pulses - development of a new concept that the Palisades was intruded as multiple pulses of magma (at least eight) that transmitted huge quantities of basalt to the surface from deep sources where fractionation and contamination occurred before injection into the Palisades. This concept replaces the idea that most chemical variation within the Palisades is due to in-situ fractionation;
3)Correlation of Palisades layers with Watchung basalt flows - the unresolved correlation of individual layers of Palisades rock with overlying basalt flows based on a) geochemical evidence and b) mineralogical evidence;
4) The Olivine Zone - the unresolved origin of the olivine layer. Is it an olivine cumulate (F. Walker (1940), a facies produced as a contact effect during the intrusion of the second magma (Walker, 1969), an intrusion of a separate OLN magma batch (Husch 1989), or the emplacement of olivine and CPX enriched crystal mush from an unspecified source (Steiner et al. 1992).
5) The Sandwich Horizon and Granophyres – what was the role of contamination vs. fractionation in their development?
6) Trondhjemites and syenite – what was the source of trondhjemite melt that has been injected into the Palisades as several thin cross-cutting veins and syenite bearing migmatite found at the base of the sill?
7) The source of the Palisades (CAMP) magma – probably the most controversial aspect of Palisades research.
Each of these issues will be discussed in this guidebook. The field-trip stops that we have selected will display evidence bearing on these issues and will hopefully stimulate lively discussions. But first a brief review of the Geologic setting of the Palisades intrusive system and its position within the ENA and CAMP (Central-Atlantic-Magmatic-Province) classification system.

STOP 1. Xenolith fusion (trondhjemite) at Graniteville, Staten Island
At this stop we will examine a xenolith of argillaceous Lockatong Formation enclosed in Palisades diabase that has undergone partial fusion to yield a trondhjemite. The sodium-rich slab-like xenolith of argillite is 30 m long, 0.5 m thick and strikes N 30° E with a vertical dip. The xenolith was derived from Lockatong located below the sill. Completely surrounding the xenolith is a coarse-grained trondhjemite. Chemical analyses (Benimoff and Sclar, 1984) reveal that there was diffusion of ions across the liquid/liquid interface between diabase and trondhjemite melts. Fe, Mg, and Ca diffused into the trondhjemite, whereas Na, Rb, K, Ba and diffused into the diabase.
The diabase is composed dominantly of plagioclase (An61Ab38.8Or0.2) and augite (En34-44Fs17- 31Wo35-42). The augite contains exsolution lamellae of pigeonite on (001), and typically exhibits simple contact twinning on (100). A granophyric intergrowth of quartz and K-feldspar is present in minor amounts. Grains of titanomagnetite with oxidation lamellae of ilmenite and discrete grains of ilmenite are common.
The trondhjemite is composed dominantly of quartz-albite granophyre containing large discrete crystals of albite and Ca-rich pyroxene. Minor constituents include interstitial calcite, titanite, ilmenite, optically homogeneous titanomagnetite, nickelian and cobaltian pyrrhotites, apatite, and sphalerite. The modal mineral percentages are clinopyroxene 38, albite 38, quartz 18, titanite 2.7, calcite 1.3, and opaques 2.0.
Petrographic examination shows that the xenolith is now a hornfels and exhibits a hornfelsic texture. The hornfels is composed dominantly of albite and quartz and subordinantly of calcite, titanite, apatite, ilmenite, and actinolite. The modal mineral percentages are albite 66, quartz 30, titanite 2.3, calcite 0.9, apatite 0.5, and actinolite 0.3. The bulk composition of the xenolith is variable, as shown in Table 1 of Benimoff and Sclar (1984) which is not unexpected for a meta-sedimentary rock. Normative albite ranges from 56.4 to 80.2 wt.%, whereas normative quartz ranges from 7.0 to 35.4 wt.%.

STOP 2. The Olivine Zone (Palisades Park, Fort Lee)
From River Road turn into Henry Hudson Drive; The olivine zone is on the left side of the road near the first left curve. (Latitude 40.846969°; Longitude -74.153697°
The olivine zone (hyalosiderite) occurs 7 to 20 meters above the base of the southern portion of the Palisades sill but is less well defined within the northern portion because it is replaced by a more hypersthenes-enriched facies with less olivine (altered to iddingsite) but with similar whole rock chemistry, particularly Cr/Mg ratios (Steiner et al, 1993). The northern end of the olivine layer is exposed at Nyack Beach State Park (Stop 6 of this field guide).
OHM 2019: Note that the latitude and longitude given are not correct.

STOP 3. Trondhjemite and Syenite fusion (Ross Dock)
Continue on Henry Hudson drive and park at Ross Dock. Walk up to traffic circle and outcrop is just west of the circle at Latitude 40.857369° and longitude -73.959189°.
The chill zone at the base of the sill is clearly exposed along the park road above Ross Dock. The diabase here is aphyric except for glomeroporphyritic aggregates of pyroxene and plagioclase and contains very few xenoliths; characteristics shared by the Orange Mt basalt. The lower contact is largely parallel to the bedding planes of the underlying metasediments but is locally discordant. Flow of the first pulse of diabase through the Lockatong argillite has excavated a few channel-like cuts several meters across that truncate underlying Lockatong bedding plains at about 30°. In addition, anticlinal dome-like structures consisting of Lockatong Formation that rise a few meters into overlying diabase are exposed here (Fig. 5). It is at these dome-like structures where fusion has occurred.
Four meters of the section directly below the Palisades contact where considerable fusion has occurred includes 0.3 m of "buff arkose" in contact with the diabase, underlain by 0.2 m of "bedded siltstone", underlain by 2.9 m of "buff arkose" underlain by 1 m of "platy and bedded siltstone" and 0.5 m of "laminated siltstone". These lithologies have been described by Olsen (1980) as meta detrital cycles and he has correlated them continuously for 12 km along the base of the sill. The uplift of the black "laminated siltstone" has brought it to close proximity to the sill contact. The domed structures may have involved movement of volatiles derived from brackish groundwater. The salt content of these volatiles may have helped flux the melting process. Each of the lithologies exposed at the stop 3 dome exposure have been chemically analyzed by Benimoff and Puffer (2000). Both the syenite and trondhjemite fusion products are sodic typically containing 4 and 7.5 % Na2O respectively, but K2O and Rb is highly partitioned into the syenite, typically containing 5% and 125 ppm vs. only 0.5% and 25 ppm for the trondhjemite. Both the syenite and trondhjemite have similar REE contents comparable to the Lockatong Argillite (Benimoff and Puffer, 2000). The syenite, trondhjemite, and Lockatong laminated siltstone each display negative Nb anomalies in contrast to the Palisades diabase.

STOP 4. Alpine
(near Exit 2 Palisades Interstate Parkway; close to Palisades Interstate Park Headquaters)
The central portion of the Palisades sill is exposed along an extensive section extending from about 60 m above the base to approximately the 150 m level. Portions of this section are characterized by cm-scale rhythmic banding (Fig. 6). Thin sections (Block, et al, 2004) reveal associations of plagioclase and CPX tend to be separated by finer-scale plagioclase chains consistent with a convective flow model. Thin sections also reveal that the rhythmic banding is complicated by a cryptic mm-scale banding.
OHM 2019: No latitude and longitude given so this location is from NYSGA 1998 trip A5 stop 1.

STOP 5A. Coarse Augite Dolerite (Valley Cottage)
As described by Steiner (1989) this is one of the few localities not in someone's yard which shows coarse augite dolerite (granophyre). However, the exposure here is weathered. The iron-enrichment of the Palisades at this stop is due to abundant titanomagnetite in the groundmass that will attract a magnet. The titanomagnetite is often dendritic and is considered to occur as both a primary and a quench feature. Chemically and to a certain extent petrographically this coarse dolerite appears to be equivalent to the late stage ferrodolerite, fayalite granophyres and other facies of Walker (1969), except that the iron enrichment is not accompanied by iron rich ferromagnesian minerals such as ferroaugite or fayalite. Ferroaugite rims may occur, but the bulk clinopyroxene is clearly augite.
REE patterns (Steiner, 1989) indicate extreme enrichment and are consistent with the derivation of the coarse augite dolerite from pigeonite facies through crystal liquid fractionation.

STOP 5B. The Upper Contact (Route 303 and Lake Road in Valley Cottage)
Parking can be accommodated at the local deli, across the street at the Bank, or in the large Valley Cottage Parking lot one block west on Lake Road; the latter will accommodate buses.
One of a few rare outcrops of the upper contact of the Palisades is exposed near the intersection of Route 303 and Lake Road in Valley Cottage and has been described by Steiner (1989). Another upper contact exposed about 3.2 km to the south is also described by Steiner (1989). The Valley Cottage location marks a sharp boundary between baked lake sediments and the upper quench zone contact with the Palisades. NYSGA members on the trip are challenged to find the contact. Note that the bench or small ridge that runs roughly east west toward Rockland Lake (from the intersection toward the Chase bank looking across the structure) represents the contact metamorphic zone. This location is on the partially exposed 'ring-dike' structure at the northernmost termination of the Palisades that extends northward along the Hudson toward Haverstraw than arcs westward, circling back to this location comprising in map view a large circular structure.
The texture of the contact diabase is microporphyritic with augite microphenocrysts. Within 2 meters of the contact the texture is ophitic, and beginning about 5 meters south patches of interstitial mesostasis appear. Farther south the diabase appears to plunge beneath the sedimentary cover. About 1 km north of Lake Road the contact reappears on the upper portions of the exposed slope which is inset 60 meters east of route 303. The dolerite dips roughly west at about 45 degrees under a veneer of shales. The intrusive contact is, therefore, complex, winding in a curvilinear fashion along its margin the general form of poorly exposed coalesced domes or localized arches.

STOP 6. Nyack Beach State Park
Enter Nyack Beach State Park, curve around the toll booth and follow paved incline up the hill to the left. Turn left at the top of the hill approximately 100 yards to the circular turn around and park. Latitude 40.95305°; Longitude -73.920490°)
Steiner (1989) described in detail the geology of Nyack Beach State Park. The escarpment at the eastern edge of the park represents the western wall of an infilled stone quarry. On this rock face, at approximately 13 meters above the presently obscured basal contact, a subhorizontal "rotten zone" can be observed. This zone presumably represents the last vestige of the olivine layer referred to by Walker (1969). It appears to fade northward of the present location.
A close up view of the olivine zone reveals that the basal part is undulose and uneven. It is marked by nodules of basalt enclosed in a weathered granular matrix. An analysis of one of the olivine bronzite nodules yields 10 percent MgO. This percentage is high for most of the Palisades, but less than the 19 percent reported by Walker (1969) for the hyalosiderite facies. Here, as elsewhere, it appears that cooling cracks are reasonably continuous through the olivine zone indicating that it belongs to the same cooling unit as the overlying dolerite.
OHM 2019: The latitude and longitude given are for the Palisades Interstate Park Headquarters, near stop 4. This location is from the description.

4: FOSSIL GREAT LAKES OF THE NEWARK SUPERGROUP – 30 YEARS LATER
Paul E. Olsen
Lamont-Doherty Earth Observatory
of Columbia University, Palisades, NY 10968
ABSTRACT
In the 1980 NYSGA meeting (Olsen, 1980b) I led a field trip to look at strata of the Triassic and Jurassic great lakes of the Newark basin which are among the largest lakes known of any time. Our view of these giant lake systems has been much amplified since that time because of the collection of industry seismic lines, the drilling of two deep exploration holes, about 40,000 ft of core by the Army Corps of Engineers, 26,700 ft of core by the Newark Basin Coring Project (NBCP), and quite a few Ph.D. theses (including my own). The purpose of this fieldtrip is to examine outcrops and related cores in the Newark basin, that illustrate some of the key features of these giant lake strata and interbedded flood basalts and how they play key roles in current debates on climate change, mass extinctions, evolution, ascent of the dinosaurs, the rifting process, carbon sequestration, and chaos in the Solar System.

4: FOSSIL GREAT LAKES OF THE NEWARK SUPERGROUP – 30 YEARS LATER

STOP 1. Lamont-Doherty Earth Observatory (Machine Shop Area)
Newark Basin Cores, Palisade Sill Outcrop, and Borehole Through Sill.
Latitude and Longitude: 41° 0.239'N, 73° 54.760'W.
Stratigraphic Units: Stockton – Boonton Formations and Palisade Sill
Age: ?Late Carnian (early Late Triassic) to Early Jurassic (∼230-200 Ma)
Main Points:
1. Representative cores of the Newark basin
2. Lacustrine cyclicity
3. Correlation between Newark and Hartford basins based on core and outcrop
4. Pompton Tuff and the size of the great lakes
5. Carbon sequestration
Cores: Cores will be on display of all of the formations of the Newark basin (Figure 10) as well as a core of the Shuttle Meadow Formation of the Hartford basin (Figure 18) for comparison with the Feltville Formation. Detailed descriptions and interpretations of the sedimentology of these cores and related outcrops are given by Smoot (2010).
Core 1: Stockton Formation, Prallsville Member (Figures 7, 10).
This segment of core is from the Princeton no. 1 core drilled on Princeton University property near the Forrestal Campus (Kent & Olsen, 1995) (Figure 1). It is a fluvial sandstone with some of the highest directly measured porosity and permeability in the basin (3174.50 ft: 131-118 millidarcys permeability, 14.2-14.0% porosity). The Prallsville Member is below the postulated tectonosequence boundary in the Stockton (Figure 7) and is thus of Late Carnian age at about 231 Ma on the NBAGPTS.
Core 2: Lockatong Formation, Tohickon Member (Figures 7, 10).
This segment, from the Nursery no. 1 core (Figure 1) taken off Nursery Road in Ewing Township, is representative of the middle Lockatong Formation and shows nearly one complete Van Houten Cycle. The age of this unit is Early Norian about 219.5 Ma on the NBAGPTS. This represents one of the cycles deposited during times of high precessional variability, but does not represent the deepest of the Lockatong lakes and has not produced any fossil fish in outcrop. This core has well-developed pinch-and-swell lamination and some bioturbation in the deeper water intervals, polygonal desiccation cracks, and brecciated massive mudstone. When the brecciated massive mudstone is very well-developed it is difficult to see anything at all in the core. According to Smoot (2010) the brecciated massive mudstone formed by repeated wetting and drying of mud initially deposited in standing water in a playa with cracks forming over previously filled cracks.
Core 3: Passaic Formation, Cedar Grove Member (Figure 7).
This long segment is from the Weston Canal no. 1 core near Zarephath, NJ. shows much of a 100 ky cycle at around 207.4 Ma. The Cedar Grove Member is one of the most easily mapped units being identified from Newark New Jersey along Route 287 to near Birdsboro, PA. This is a nice example of penecontemporaneous gypsum including abundant nodules and anhedral crystals. According to Smoot (2010), the crystal styles and upward-coarsening successions resemble modern gypsum soil occurrences (Smoot and Lowenstein, 1991) where gypsum dust is blown onto the surface, and then redistributed downward by rainfall rather than gypsum crystallizing out of brines in playas. There are also veins of various orientations filled with fibrous gypsum that formed much later. The muds themselves however formed in very shallow lakes, with the gypsum dust possibly being blown in from very far away (as suggested by Smoot, 2010) along with a considerable amount of lithic dust. The lower part of the member has a Van Houten cycle with one of the best-laminated deep-water intervals in the Passaic Formation. The very well developed nature of this cycle contrasts with the poorly developed succeeding cycles. In outcrop this well-developed cycle has produced palynomorphs and reptile footprints of characteristic Triassic aspect including the silesaurid dinosauromorph track Atreipus milfordensis, the crurotarsian Brachychirotherium cf. parvum, and the lepidosauromorph Rhynchosauroides sp.
Cores 4 & 5: Passaic Formation, Exeter Member and Orange Mountain Basalt (Figure 7, 10).
Two cores are shown here from the Passaic Formation – Orange Mountain Basalt contact. Core 4 is a segment of the Martinsville no. 1 core of the NBCP from Martinsville, NJ from a more central basin location and Core 5 is part of the ACE series, PT-38, spanning the same interval but closer to the northern edge of the basin. Outcrops of this interval in the Jacksonwald syncline have darker shales and much more obvious cyclicity.
In addition to the facies change seen across these three sites, from better cyclicity with dark gray shales in the deeper water units in the southwest, to obscure cyclcity in red beds in the northeast, there is also a parallel change from more or less consistent vertical patterns of cycles to a vertical pattern with fully fluvial conglomeritic facies below to a more marginal lacustrine facies above at the site of PT-38. The Jacksonwald area has been a major source of evidence on the initial ETE, including abundant Triassic-aspect crurotarsian tracks such as Brachychirotherium and Apatopus, while outcrops adjacent to the location of PT-38 have produced a post-initial-ETE assemblage with abundant theropod dinosaur tracks including Eubrontes giganeteus as well as the crocodylomorph track Batrachopus and a new species of Rhynchosauroides. Also present is a Brachyphyllum-Clathropterus macrofossil assemblage with a Classopollis-dominated sporomorph assemblage.
Cores 6, 7, 8: Feltville Formation, Washington Valley Member and Orange Mountain Basalt (Figure 10) and Shuttle Meadow Formation (Figure 18).
Van Houten cycles in the lower Feltville Formation (Washington Valley Member of Olsen 1980a, 1980c) are unusual in the Newark basin in having deeper water intervals that are very carbonate rich, often limestones. These cores display the lower Feltville Formation in the Martinsville no. 1 core of the NBCP (Core 6) and PT-14 of the ACE cores (Core 7) , and the correlative part of the Silver Ridge B-1 core of the Shuttle Meadow Formation of the Hartford basin (Core 8). These cores were essential to understanding the cyclostratigraphy of the Feltville and Shuttle Meadow Formation and hence to the chronology of the continental Triassic-Jurassic boundary. In fact, it is doubtful that the basic stratigraphy could have been worked out in outcrop without the model and testable hypotheses provided by both the ACE and Silver Ridge cores.
Correlation between cores and outcrops of the lower Feltville Formation is now relatively straightforward. But that was not the case in 1980 when there were only outcrops to work with. Having not seen more than one lake level cycle in superposition I had a stratigraphic model in mind in which there was only one lake level cycle in the Feltville Formation. I interpreted various outcrops along strike accordingly and assumed the dramatic differences between outcrops was due to lateral change (Olsen et al. 1980). I had the same model in mind for the lower Shuttle Meadow Formation. However, when the ACE cores of the Feltville were examined in 1985 it was obvious that there were several Van Houten cycles in the lower Feltville (Olsen et al., 1988; Fedosh & Smoot, 1988). Instead of one carbonate-rich lake level cycle there were two. I revisited the type section of the Feltville (our Stop 3) and was able to test the outcrop generality of this pattern by digging that there were indeed 2 carbonate bearing cycles and then in late August, 2010, I did the same at our Stop 2. This has allowed unambiguous correlation of the cycles in the lower Feltville laterally. One pattern emerging from this correlation (Figure 18, 19) is a progressive thinning and onlap of the lower Feltville onto the Orange Mountain Basalt along strike from the northeast to the southwest, prima facie evidence of syndepositional folding in the Watchung syncline.
Comparison of the stratigraphy of the lower Feltville and Shuttle Meadow Formation reveals another pattern, and that is that the cyclostratigraphy is more subtle and complicated than expected. Correlation between the Shuttle Meadow Formation and the Feltville is surprisingly obvious (Figure 18), but it makes clear that rather subtle lithological features seen in outcrop and core of the Feltville have important cyclostratigraphic implications. In order to facilitate discussions about Feltville cyclostratigraphy I have given names to the individual deeper water units within the Washington Valley Member (Figures 10, 18). Whiteside et al. (2010) shows that the cyclostratigraphy of the Shuttle Meadow Formation reflects not only the ∼20 ky climatic precession cycle but also a ∼10 ky hemiprecessional cycle. In specific the Cataract Hollow, Trailside, and Vosseller beds reflect mostly the ∼20 ky cycle, while the Lake Surprise Bed reflects largely the ∼10 ky cycle. The presence of this hemiprecessional cycle outside the equatorial tropics is not expected of local insolation forcing and suggests an expansion or export of equatorial climate variability and an enhancement of the hydrological cycle perhaps due to the super-greenhouse conditions of the syn-CAMP world.
A 10 ky hemiprecessional cycle caused by direct forcing should be limited to ±5° of the equator, while the Shuttle Meadow Formation was deposited at about 21° N.
Cores 9 & 10: Preakness Basalt: Flow number 2.
We will see the stratigraphy of the lower Preakness Basalt at Stop 4, but what we will not see there are the gabbroid layers that characterize parts of flow 2. These are important because in some areas they contain zircons that crystallized from the melt and provide high-resolution dates for the flow (e.g. Blackburn et al., 2009). Several segments of ACE cores PT-20 (Core 9) and C-97 (Core 10) will be on display showing these gabbroid layers. These particular layers did produce zircons but these were all apparently assimilated from crustal rocks through which the feeders flowed (S. Bowing, pers. com.) as they have ages 100s of millions of years older than the crystallization age.
Cores 11 & 12: Towaco Formation and Pompton Tuff.
The Towaco Formation is especially well represented in the ACE cores with many parts of the formation being represented by multiple cores. At Stop 5 we will see the 3 prominent Van Houten cycles formed during times of maximum precessional variability in the middle Towaco Formation. The bed names for each of the prominent deep-water units for these cycles are given in Figure 9. Portions of cores C-128 and PT- 14 (cores 10 & 11, respectively) that contain the Colfax Road Bed are on display. This bed contains the Pompton Tuff, an airfall ash we will see in outcrop at Stop 5, but here we see it in two cores. The Pompton Tuff also extends to the Hartford basin where it is known from 4 localities a slab from one of these will be on dispaly as well.
Philpotts (in Olsen et al. 2005 and paraphrased here) described this unit in the Hartford basins as thin bed that tends to erode proud of the surrounding deep-water lacustrine unit. The only detectable particles in the layer are all euhedral plagioclase laths with a high aspect ratio that show no signs of rounding. They must have originally been enclosed in glass that is now converted to a clay or to what appears to be chalcedony. There are small circular areas that contain a mottled gray birefringent material that looks very much like chert. These observations are entirely consistent with the small laths of plagioclase being part of a basaltic crystal tuff. There are also small rounded particles that seem to be bits of basalt. The tuff would seem to represent an explosive eruption of the CAMP that is separate from those that produced the stereotypical sequence of known CAMP flows.
What you can see in these cores, the thin sections on display, and slabbed portion of the Westfield bed of the East Berlin Formation of the Hartford basin is a very close match not only between the tuff, but also between the surrounding laminae. As discussed above the similarity is so strong that it seems plausible the lakes in the two basins were connected.
Core 13: Hook Mountain Basalt.
On display is an ACE core C-104 in the Hook Mountain Basalt which exhibits thin gabbroid layers. These too produced only zircons inherited from crustal sources.
Core 14: Boonton Formation, Rockaway River Bed (Boonton fish bed)
The Boonton Formation as sampled in the ACE cores closely resembles the Towaco Formation in its pattern of cyclicity and facies. ACE core PT-6 on display includes the famous bed that produced abundant fish described from the Rockaway River in Boonton, New Jersey, named here the Rockaway River Bed (Figure 10). The semionotids from this bed comprise a distinct species (20).
Lamont Carbonation Experiment Borehole
A borehole drilled at LDEO has been used for experiments in carbon sequestration carbonation using in situ carbonation in mafic igneous rocks, in this case diabase (Matter et al. 2007). Palisade diabase is visible behind (west) of the borehole site. The small small-scale CO2 injection experiment at this site showed large decreases in Mg++ and Ca++ concentrations over short periods of time (200 hours) suggested both mixing between the injected solution and aquifer water and the release of cations from water–rock dissolution, that neutralized the introduced carbonic acid (Goldberg et al. (2010). This the same kind of reaction that would result in the weathering of CAMP basalt flows and the accumulation of carbonates in the early CAMP lakes of the lower Feltville Formation, which now has the potential to sequester the carbon from the burning of fossil fuels. As Goldberg et al. (2010) point out, if large CAMP reservoirs are found in proximity to major industrial carbon sources huge volumes of CO2 could be sequestered permanently by the in situ carbonation reaction.

Proceed south on Rt. 9W along the strike of the Palisade sill.
There fill be small exposures of the sill along Rt. 9W towards Fort Lee.

Continue onto Fletcher Ave.
Exposures on north side of ramp for NJ-4 of coarse gabbroid of Palisade sill. This gabbroid produces zircons yielding a very precise age (Blackburn et al., 2009).

Driving down the dip slope of Palisade sill.
Exposures to north along US-80/I-95 reveal contact of the sill and overlying Lockatong Formation.

Exposures of Orange Mountain Basalt.

Contact between Feltville Fm and overlying Preakness Basalt.
Approximate contact between Feltville Formation and overlying Preakness Basalt. Notable is the high degree of distinctive splintery fracturing that characterizes much of the second Preakness flow, which we will see up close at Stop 4.

Passing into Feltville Formation.

Route follows strike of Feltville Formation
Route follows strike of Feltville Formation, mostly on or near the contact with the Orange Mountain Basalt.

Route now follows along middle Feltville Formation.

Heading down section in Feltville.

STOP 2. Lower Feltville Formation (Washington Valley Member).
On right is unpaved access to Eastfields Park of Somerset County Park Commission. Entrance is on upper Orange Mountain Basalt.
Stratigraphic Units: Lower Feltville Formation, Washington Valley Member, Orange Mountain Basalt
Age: Latest Triassic (Latest Rhaetian) to ?earliest Jurassic (201.3 Ma)
Main Points:
1. Condensed section of Washington Valley Member
2. Best exposure of Vosseller Bed
3. Very condensed section of Cataract Bed
4. Onlap onto Orange Mountain Basalt
5. First 100 ky after initiation of ETE
6. Limestones as products of super-greenhouse
7. Intense disruption of Vosseller Bed and "dead horses"
8. Species flocks of semionotid fishes
9. Dinosaur tracks
Walk about 250 ft north to outcrops along Blue Brook and walk downstream past the outcrops along the north bank of the stream about 800 ft west to the contact with the Orange Mountain Basalt.
About 12 m of Feltville section outcrops here. The complete Van Houten cycle containing the Cataract Hollow Bed outcrops along with nearly the complete cycle containing the Vosseller Bed, this being the best outcrop of the latter. The section is closely comparable to what is seen in the Martinsville no. 1 core, except it is even more condensed. The section begins with the vesicular upper surface of the Orange Mountain Basalt overlain by a decimeter of basalt gravel and cobbles in a bluish-gray mudstone. This is followed by a decimeter of gray/white, seemingly? oscillatory rippled sandy calcarenites passing up into two meters of red mudstone. This bed is clearly the Cataract Hollow Bed. In my section of this interval in 1980 I completely missed this bed., because I did not have an expectation of its existence. In August 2010, I looked for the Cataract Hollow Bed in the completely submerged interval near the Orange Mountain Basalt. This illustrates the need to have some kind of rigorous testable hypothesis of what should be present. Without that, why would I explore every hidden nook and underwater cranny.
The red beds above the Cataract Hollow bed is overlain by 20 cm of blue gray mudstone with fabrics like the underlying red mudstone. This is abruptly overlain by ripple crosslaminated gray fine sandstone with sole casts of dinosaur tracks. These tracks are so far all brontozooids (grallatorids).
Above the ripple crosslaminated sandstone is a grey mudstone with floating blocks to flakes of black laminated to microlaminated limestone and claystone. Presumably, these blocks once comprised continuous layers. They are in fact comparable to what I have termed "dead horses" (Olsen et al., 1989), although these are much larger clasts ("horses"). These blocks generally exhibit signs of bedding plane-parallel shear, including folds and imbricate thrust faults. The name derives from the term "horse" for a fault-bounded sliver of rock and their "dead" or dismembered condition and the name was coined to call attention to the phenomenon. The gray mudstone shows few or no depositional sedimentary structures. There is no well-defined upper surface of the bed. In this and other deposits such as the East Berlin Formation (Olsen et al., 2005), or Towaco Formation (Stop 1), the associated massive mudstone suggests that partial liquefaction accompanied the deformation that produced the dead horses, and I interpret them as a form of low-pressure structural mélange. These features are common in fine-grained organic rich rocks but they have usually been interpreted as depositional units, such as muddy turbidites (e.g., Dyni & Hawkins, 1981). Dead horses are still a feature of the Vosseller Bed at Stop 3, but seem absent in the ACE cores.
The limestone blocks themselves can be more than a meter in diameter and 30 cm thick, especially those with folds. Fractures in the limestone contain a tarry bitumen that is liquid, if highly viscous, at body temperature but generally solid in the water. However, the oil slicks that appear on the streams surface when blocks are pried loose from the matrix attest to the presence of more fluid hydrocarbons. The thermal maturity of these beds are within the oil window based on a vitrinite reflectance value of 1.18 R0% from the Vosseller bed of the nearby Martinsville no. 1 core (Malinconico, 2009), and the hydrocarbons present were surely generated from the limestones.
These blocks of limestone themselves contain mostly articulated, and some disarticulated fish, including Semionotus, Redfieldius, and Ptycholepis (Figure 21) The presence of coprolites suggests the presence of coelacanths yet to be found. The semionotids comprise a species flock with most variation being in overall body shape and the morphology of the series of spined scales, called dorsal ridge scales along the dorsal midline (Figure 14). In fact the name Semionotus is derived from "signal back". Preservation is often exquisite and with chemical preparation extremely fine details can be seen. In chemical preparation, the side of the fish exposed upon splitting the rock is embedded in a resin such as epoxy or polyester and the maturix is subsequently removed by dissolution in acetic acid, leaving the bone adhering to the plastic. McCune recorded six species in the Feltville (McCune et al., 1984; Olsen et al., 1989).
The origin of the carbonate so prevalent in the Vosseller, Cataract Hollow, and Feltville in general is worth commenting on because such carbonate rich beds are virtually absent from the rest of the Newark basin. Carbonate and limestones are not at all uncommon in lakes, and such famous units as the Green River oil "shales" are in fact carbonates. The carbonate was mostly derived from biologically mediated chemical precipitation in the upper part of the water column, rather than from the tests of organisms. As discussed above, the unusual amount of carbonate in the Feltville and in fact in all of the post-initial CAMP basalt flows in central Pangea may relate to weathering of the CAMP basalts themselves under super-greenhouse conditions in the first 100 ky after initiation of ETE.

STOP 3. Lower Feltville Formation (Washington Valley Member) Type section.
Stratigraphic Units: Lower Feltville Formation, Washington Valley Member, Orange Mountain Basalt
Age: Latest Triassic (Latest Rhaetian) to ?earliest Jurassic (201.3 Ma)
Main Points:
1. More expanded section of Washington Valley Member
2. Best exposure of Cataract Bed and superposition of Vosseller bed.
3. Fissures in Orange Mountain Basalt
4. Copper at contact with Orange Mountain Basalt
5. First 100 ky after initiation of ETE
6. Limestones as products of super-greenhouse
7. In situ Clathropteris
9. Dinosaur tracks
Walk southeast and then southwest to the beginning of the loop near the end of Cataract Hollow Road about 2090 ft from the parking area. At the trail head, follow trail to southeast 330 ft and then about 600 ft to the northeast along the raised path (old canal levy) to Station 1 from where we will proceed to 3 additional stations to cover the stratigraphy at the type section of the Feltville Formation (Figure 19). Feltville is the name of the abandoned village of Feltville along Cataract Hollow Road, now part of the Watchung Reservation of the Union County Department of Parks and Community Renewal.
Station 1 at about 40° 40.747'N, 74° 22.718'W is an outcrop of pink, gray, and white limestone interbedded with red siltstones and fine sandstones. This is the best vertical outcrop of the Cataract Hollow Bed and its type section. Fragmentary to articulated fish and occasional coprolites occur in the lower laminated part of the limestone. The fish bones and scales are pink and dark brown. The upper carbonate beds at this station are calcarenites that grade into the overlying red beds. The laminated and laterally continuous nature of the base the Cataract Hollow Bed as well at the articulated fish shows that it was deposited in quiet water, below wave base, generally lacking oxygen in contrast to the bed at Stop 1.
To the southeast, on the opposite side of Blue Brook is a ravine that cuts down down the dip-slope of the Orange Mountain Basalt. Thin to thick-bedded red siltstones of the basal Feltville Formation fill what is clearly a fissure in the basalt. Such fissures are common in the Orange Mountain Basalt and can cut down through much of the Formation, as seen at various quarries. In Nova Scotia, such fissures contain tetrapod bones, and it quite likely they do here as well, although this site has not been sufficiently prospected.
Proceed 500 ft northeast to bluff on west side of southeast flowing tributary (out of Cataract Hollow) to east-facing bluff that is Station 2.
Station 2 at approximately 40° 40.822'N, 74° 22.718'W is an outcrop of poorly exposed black laminated carbonate and mudstone of the Vosseller Bed and surrounding gray clastics. Careful examination of the geometric relationship between this outcrop and Station 1 shows that this bed in superposition to the Cataract Hollow Bed, but this can be seen unambiguously at Station 4. Proceed southeast along the trail 270 ft crossing the small south-flowing tributary at Cataract Hollow and proceed about 620 ft to trail heading east up the slope (noting limestone of the Cataract Hollow Bed in the path). Continue 250 ft east to Station 3.
Station 3 is at about 40° 40.860'N, 74° 22.718'W and consists of an outcrop extending from this ridge to the stream below and to the south. The contact between the Orange Mountain Basalt and the overlying Feltville is nearly at stream level and the overlying beds consist a nodular limestone succeeded by the transgressive portion of a Van Houten cycle bearing the Cataract Hollow Bed, the Cataract Hollow Bed itself and the overlying regressive red beds of the cycle, which we saw better exposed at Station 1. The larger blocks of the nodular limestone are very fine-grained and contain darwinulid ostracodes. The gray sandstones and siltstones of the transgressive portions of the cycle conatin plants in groth position including the horsetail Equisetites and the fern Clathropteris as well as dinosaur footprints. The Cataract Hollow Bed is deeply weathered here and invaded by modern tree roots, and the overlying beds are highly weathered. Just upstream from this station is the old copper mine described by Manspeizer (1980) at this site. I do not think there is evidence of intrusion here and the thermal maturity of the organic material here is not elevated. Proceed north and down the slope about 150 ft to path and walk about 960 ft northeast to Station 4 on the bluff on the north side of the west flowing tributary. Station 4 is at about 40° 41.015'N, 74° 22.718'W and has good outcrops of the Lake Surprise Bed, Vosseller Bed, through the Trailside Bed and then poor outcrops down through the Cataract Hollow Bed. It was at this site that I was able to confirm the superposition of the Vosseller and Cataract Hollow beds by digging for the latter after seeing the ACE cores. The Trailside Bed consists of purple and gray siltstomnes containg abundant Brachyphyllum. The cyclostratigraphic equivalent Stagecoach Road bed of the Shuttle Meadow Formation is a black calcareous mudstone with whole fossil fish and conhcostracans. The Lake Surprise Bed is a finely laminated black shale bed here with partly articulated Semionotus. The Vosseler bed is unfortunately very weathered and crumbly, although I have found articulated fish in it here.

STOP 4. Upper Feltville Formation and Preakness Basalt, William Paterson University.
Stratigraphic Units: Upper Feltville Formation, Preakness Basalt (flows 1 and 2)
Age: Earliest Jurassic (201.1 Ma)
1. Upper sandy Feltville Formation
2. Contact between Feltville and Preakness Basalt
3. Basal pillowed flow of Preakness Basalt (P-1)
4. Flow P-2 of Preakness basalt with low paleomagnetic inclinations
5. Largest single flow in world?
6. CO2 sequestering possibilities in basalt
Walk west from parking area about 290 ft to entrance to abandoned quarry on south side of West Overlook Ave head towards stream walking about 300 ft to open area of the old quarry.
Manspeizer (1980) described this locality in that year’s NYGSA guidebook noting the three basic units present. The upper Feltville Formation, a lower pillowed flow of the Preakness Basalt and a second massive and highly fractured flow of the Preakness Basalt. The Feltville Formation exposed in the old quarry and adjacent stream consists of interbedded tan and red sandstones and red and gray and purple siltstones. The latter contain sporomorphs and conifer fragments. In terms of the cyclostratigraphy of the Feltville this sequence is the interval of maximum precessional variability in the 100 ky cycle exhibiting the lowest precessional variability of its 405 ky cycle. The contact with the Preakness has a cyclostratigraphic age of about 201.1 Ma.
The basal flow of the Preakness as exposed here consists of a complex of pillowed basalts and the more massive flow lobes that fed the pillows all of which show considerable vesicularity. This is Preakness flow P-1 of Tollo & Gottfried (1992) and is a distinct and mappable unit extending at least from the ACE core transect to the north to near the border fault. It seems to absent from at least West Orange (I-280) to near Somerville, NJ, but reappears along I-275 at Pluckemin, NJ. I (Olsen, 1980a, 1980d) described outcrops of the lower flow but did not different it from the overlying flow P-2 of Tollo & Gottfried (1992). At this locality there is little or no visible metamorphic effect on the underlying Feltville Formation, which to be expected because P1 was extruded into water, presumably as deep as the thickness of the pillowed flow itself.
Proceed from the quarry up the hill on the north to West Overlook Avenue and then to the west to exposures of basalt. The contact between P-1 and Tollo & Gottfried’s (1992) flow P-2 can be seen here. P-2 is the very thick flow that is present all over the entire extent of the Preakness Basalt and is characterized by having an intense splintery or prismatic fracture (Faust, 1975) and gabbroid layers (Puffer & Volkert, 2001). Prévot & McWilliams (1989) noted that this flow has unusually low magnetic inclinations compared to the other Newark basin flows. They also found the same low inclinations in the second flow of the Hartford basin Holyoke Basalt and the Deerfield basin Deerfield Basalt. Hozik (1992) showed that the Sander Basalt shared the low inclinations unlike all the other basalts of the Culpeper basin. All of these low-inclination flows have the same chemistries (Puffer, 1992, 2003) and all have gabbroid segregations and all but the Deerfield Basalt have the characteristic splintery fracture. In the Hartford and Deerfield basins, a flow of similar chemistry but having a tendency to be pillowed is present below the flow with the low inclinations. As pointed out by Prévot & McWilliams (1989) these directions would seem to indicate correlation, and correlation within the time frame of secular variation, suggesting that these flows represent the same eruptive event of no more than 10s or 100s of years. The Sander flow with the low inclinations is over 200 m thick, and P-2 of the Preakness Basalt is more than 90 m thick, and if the flow extended from Massachusetts to Virginia, it would be on of the largest lava flows known on Earth. In terms of environmental effects, it is surely the rate as well as the magnitude that matters, and the eruption of this flow, if it was indeed one eruption, would have had significant environmental effects. The largest single flow of the Columbia River Basalt is on the order of 5000 km3 (Tolan et al., 1989), but if the Preakness and equivalents averaged 100 m in thickness, spanned 800 km along strike, and were 100 km wide prior to erosion, it would have a volume of 8000 km3. This does not include the area spanned by dikes of the same composition that extend well into Canada (McHone, 1996).
Flow P-1 is highly vesicular at this locality, and P-2 has very significant fracture porosity and permeability. As previously discussed, Goldberg et al. (2009) argue that carbonation reaction in porous zones of basalt could provide a significant locus for carbon sequestration. The large amount of porosity and permeability is obvious here, but whether that holds at depth has yet to be demonstrated.

STOP 5. Middle Towaco Formation, The Glen, Pompton, NJ.
Stratigraphic Units: Middle Towaco Formation, Colfax, The Glen, and Pines Lake Beds
Age: Early Jurassic (200.8 Ma)
1. Classic 19th century site never exploited
2. Well developed cyclcity
3. Basin margin facies
4. Lower trophic levels well represented
5. Species flocks of semionotid
6. Tracks
7. Pompton Tuff
8. Size of lakes
The Glen is a community reserve managed by the Pines Lakes Association. Visits to this site should always be coordinated through them.
About 65 m of the middle Towaco Formation extensively outcrops along the creek and its tributaries joining Pines Lakes and Pompton Lake (Figure 22), including the top of one Van Houten cycle, two complete cycles, and the lower half of another. Three deep-water units of the upper three successive Van Houten cycles outcrop in their entirety, with the cycles averaging about 25 m thick. These three beds are termed in succession, the Pines Lake Bed, the Glen Bed, and the Colfax Bed, corresponding to the designations P-5, P-4, and P-3 in Olsen et al. (1989) and papers by McCune, respectively.
The Glen was made known as a fossil locality by W. C. Redfield (1842) who reported on the lower two shales in succession producing fossil fish and intermediate strata producing reptile tracks. It is worth mentioning that William C. Redfield, was the first president of the American Association for the Advancement of Science in 1848 and great grandfather of Alfred C. Redfield of Redfield Ratio fame.
From the parking area, walk 0.2 mi southeast across bridge and turn west into woods to the west at the small tributary to the main stream. Proceed down hill about 135 ft along tributary to Station 1.
Station 1 is at approximately 40° 59.467'N, 74° 16.083'W. Exposed in the small run is the lowest deeper water unit, the Pines Lake Bed (P-5). This unit lies on gray sandstones and conglomerates with organically preserved roots, which in turn lie on red clastic rocks. The Pines Lakes Bed is a laminate, but is not microlaminated and has rare whole fish and fish fragments. The most distinctive aspect of the bed is the presence of stromatolites around trees (Figure 23). These have been termed arboreal stromatolites by Whiteside (2004), which were a part of the assemblage of lacustrine primary producers. The Pines Lake Bed is presumably the lower of the two beds described by Redfield (1842), although he gives the distance to the next fish-bearing unit is 60 m (200 ft) while it is certainly closer to 25 m. Proceed downstream about 150 ft south to near where the stream turns west and then northwest to Station 2.
Station 2 is at about 40° 59.442'N, 74° 16.080'W. We have passed up section through gray mudstones, sandstones and minor conglomerate into reddish thin-bedded siltstones and very fine sandstones with abundant dinosaur footprints. Proceed downstream about 200 ft.
Station 3 is at 40° 59.454'N, 74° 16.116'W. Upsection from Station 3 we pass into presumably fluvial red sandstones and minor mudstones comprising the shallow water portion of the lower Van Houten cycle. The upper beds of this red sequence becomes finer grained and more highly organized. This red sequence is the interval mentioned by Redfield (1842) as being quarried by Peter M. Ryerson, Esq., of Pompton, NJ. This interval produced several dinosaur tracks, all brontozooids.
Continue downstream about 500 ft.
Station 4 is at approximately 40° 59.532'N, 74° 16.164'W at the point that the bluff comes down to near the level of the creek. Here, The Glen Bed is exposed at an accessible level. This is the upper fish-bearing unit mentioned by Redfield (1841). It is also the site of a quarry opened in 1980 by McCune and PEO, and excavated by Amy R. McCune (McCune, 1982, 1986, 1987a, 1986b, 1990, 1996, 1997, 2004).
The lower transgressive portion of this Van Houten cycle (paraphrased from Olsen et al., 1989) is characterized by an overall fining-upward trend from wavereworked conglomerates into oscillatory rippled sandstones and siltstones. The high-stand sequence begins with oscillatory-rippled siltstones, passes rapidly into laminated siltstones with pinch-and-swell laminae, and then up into a thick microlaminated interval showing silt-carbonate couplets and many sub-millimeter to decimeter thick graded distal lacustrine turbidites. One turbidite has rare 1-2 cm diameter pebbles at its base. The total organic carbon content of these beds is relatively low compared to the finer facies of the Towaco, averaging less than 2% by weight. Complete, well-preserved fossil fishes are abundant in these beds (see below). The transition into overlying non-microlaminatcd silts is abrupt, as is the correlative disappearance of fish.
A peculiar feature of several decimeters of this sequence is the presence of white to tan irregular flattened objects in some of the finest microlaminated beds. Many shapes have cuspate edges or apparent holes, while others are more rod, vermiform, or even hairlike (Figure 24). The simplest explanation of this material is that it represents devitrified and flattened tephra, largely pumice particles that fell into the lake or were washed in from accumulations along shore. The latter interpretation makes more sense because these particles are so abundant on so many laminae. However, the presence of such foamy pyroclastics implies silicic eruptions which have not yet been documented in the CAMP
Sandstone and conglomerate at the transition into the strongly regressive and lowstand portions of the cycle exhibit features suggesting wave-reworking (Smoot, 2010), including virtually all the features described by LeTourneau (1985a,1985b), such as oscillatory ripples, "fitted fabric" of pebbles and cobbles, oriented plant debris. and wellsorted layers and patches of sand, granules, and pebbles. Also present are small lenses of oscillatory-rippled sandstone nestled in well-sorted conglomerate beds. Organicallypreserved roots, and dinosaur footprints are present. Higher in the low-stand interval, the conglomerates appear fluvial in origin, although they remain to be examined in detail. These are comprise the thick sequence of conglomerate (Figure 22) referred to by Redfield (1842) as the, "variegated calcareous conglomerate" of Rogers.
Decimeter-scale folds are prominent in the microlaminated portions of this cycle. They could be subaqueous slump folds, but additional work done by McCune and PEO in the early 1980s, shows they are nappe-like drag folds of thrust faults propagating upward through major portions of the microlaminated unit. These folds show large amounts of thickening in their hinges, which are often cut by small faults. The fault-adjacent limbs are often sheared out, although completely oveturned bedding is locally present. Fish are deformed within these folds, shortened where they are perpendicular to the fold axis and elongated when they are parallel to it (Figure 25). The thrusts themselves are slickensided and sometimes polished, and they sole into bedding plane shear zones. The ductile behavior of the beds and the extremely low thermal maturity of the contained hydrocarbons (Pratt el al., 1988) demands that this thrust faulting and folding be early in the burial history of the units, prior to complete lithification, but after significant burial. An implication of these folds is that the deepwater unit is considerably structurally thickened.
On the basis of the collection of over 1700 fish made here (Figure 26), McCune described 21 species of Semionotus from the microlaminated deep-water part of this cycle, and suggested that a large proportion of them might have evolved in situ, endemic to this single lake, analogous to the endemic cichlid fishes of the African great lakes. McCune surveyed more than 2000 museum specimens from 45 localities in eastern North America and showed that six of the species in the Glen Bed were not found in deposits equal in age to or older and thus evolved within the lake level rise and high stand of the Glen Bed, with eight species occurring in older deposits and plausibly supplying the colonizing species. The evidence for seven species was equivocal. McCune (1990) showed that about 5.5% of the specimens have anomalous dorsal ridge scale patterns mixed in with otherwise stereotypic dorsal-ridge-scale patterns, and that dorsal-ridgescale anomalies are significantly more frequent in older than in younger sediments of the Glen Bed, which she interpreted as being the result of relaxed selection during the early colonization of the lake. Results of McCune’s analysis from the Glen Bed are shown in Figure 27.
Proceed over the ridge in which the quarry is located and walk about 240 ft to the west to the large north-northwest-flowing tributary to the main creek and then proceed about 360 ft south-southwest along the tributary to the large outcrops of the Colfax Bed laminite.
Station 5 is at about 40° 59.454'N, 74° 16.164'W. Here are outcrops of the Van Houten cycle bearing the Colfax Bed. The Colfax bed is similar to the Glen Bed. It is, however, much less studied. The lower few meters of the laminite have more silt and are thrown into even more folds than are present in the Glen Bed. Fish are not abundant in the Colfax Bed, but this could be because so much of the outcrop is deformed. So far only semionotids have been found.
This is the type section of the Pompton Tuff. After discovery of the small airfall ash in the East Berlin Formation (Olsen et al., 2005), I hypothesized it should be present in the Towaco Formation in the Colfax Bed, based on correlations described by Olsen et al., (1989) and Olsen et al., (1996b). Despite the fact that I had examined the Colfax Bed many times in the last 30 years, I had not noticed any ash layer. However, once knowing where to look, Gustaf I. Olsen and I found it on October 9, 2008 at this site (Figure 28). The ash is thus named after this locality, the Pompton Tuff. Subsequently, I examined the same cycle in the ACE cores and identified the tuff in ACE cores C-128 and PT-14. In the Hartford basin there are abundant conchostracans belonging to the genus Bublimnadia. Conchostracans had never been found in the Towaco Formation before but careful examination of the microlaminated interval in the homotaxial position above the Pompton Tuff revealed the same forms (Figure 29). These are representative of the lower trophic levels of consumers.
The extreme similarity in details of the Colfax Bed in terms of lake level phase, conchostracans, and the position of the Pompton Tuff in the correlative Westfield Bed in the Hartford basin would seem unusual in two isolated lakes with separate watersheds. Such similarity would not be surprising if the Colfax and Westfield beds were deposited by the same lake. If they were the deposited by the same lake and this lake extended to the Culpeper basin, it would be larger than the American or African great lakes, or Lake Baikal, as previously discussed.

Extensive exposures of Passaic Formation conglomerates.

Exposures of Palisade diabase.

Continue to follow US-9W S following strike of the Palisade sill.

5: GEOCHEMICAL CHARACTERIZATION OF NEW YORK CITY SCHIST FORMATIONS
John H. Puffer
Department of Earth & Environmental Sciences
Rutgers University
Newark, New Jersey, 07102
Alan I. Benimoff
Department of Engineering Science and Physic
College of Staten Island
2800 Victory Boulevard
Staten Island, NY 10314
Jeffrey Steiner
Department of Earth and Atmospheric Sciences
City College of New York
138th and Convent Avenue,
New York City, New York 10031
Abstract
New geochemical analyses of bedrock from Manhattan, New York support a more widespread distribution of the Manhattan Schist than indicated on recent geologic maps of New York City including Schuberth (1967); Baskerville (1994); Merguerian and Merguerian (2004) and Brock and Brock (2001). The 39 samples of schist from outcrops and roadcuts across all of Central Park, Manhattan plot as a single coherent population on all major element and trace element variation diagrams. Plots of K2O/Na2O vs. SiO2 and K2O/Na2O vs. SiO2/Al2O3 on the tectonic setting discrimination diagrams of Roser and Korsch (1986) are consistent with a passive margin to active continental margin depositional setting. Major elements also plot within the compositional field of the Martinsburg Formation, an Ordovician, largely continental shelf meta-pellite and a probable stratigraphic correlative of Manhattan Schist. In addition, samples mapped as Hartland Formation collected west of Central Park along the Hudson River plot within the continuum of the Central Park samples. An arc detritus depositional setting as generally proposed for Hartland deposition is notably un-represented throughout Manhattan. However, east of Manhattan, particularly Pelham Bay, an arc signature is seen. Our geochemical data together with ambiguous Hartland/Manhattan schist petrology underscores the need to establish a reliable mappable criteria capable of distinguishing Hartland from Manhattan schists.
There are currently at least four competing geologic maps of New York City that present highly differing formation distributions, particularly Manhattan Schist and Hartland Formation. In addition each of four competing maps including Schuberth (1967); Baskerville (1994); and Merguerian and Merguerian (2004) and Brock and Brock (2001) present highly differing tectonic and stratigraphic interpretations. Our chapter is not an attempt at re-mapping New York City but simply offers some overdue geochemical characterizations of Manhattan and Hartland formations that may be used to refine future mapping.
The status of New York City geology has only become more confusing during recent years. Currently there is no consensus on the age, the provenance of the sedimentary protoliths, or the formation identification of most schist outcrops in Manhattan despite good exposure and extensive studies by countless geologists. We will, therefore, be unable to provide a consensus answer to the most basic questions at some of the outcrops that we visit on this field trip, such as "What formation is this and how old is it?" However, we will be able to provide some of the first geochemical data on each of the outcrops we visit together with some geochemical based stratigraphic correlations and some geochemical constraints on the provenance of the sedimentary provenance.

STOP 1. Central Park
No rock collecting is permitted so don’t even bother to bring your rock hammer. However feel free to pick up loose samples and examine them with your hand lens. We will spend one hour at this stop. The bus cannot wait for stragglier.
The outcrops near 59th Street. along the southern portion of Central Park have been described as Cambrian Manhattan Formation by Schuberth (1967), (Fig. 1); as Cambrian-Ordovician Hartland Formation by Baskerville (1994), Fig. 2); as Cambrian-Ordovician Hartland Schist by Merguerian and Merguerian (2004), (Fig. 3); and as Late Proterozoic Manhattan Schist by Brock and Brock (2001), (Fig. 4). Still other options have been published and we encourage lively debate, but please leave your rock hammers in the bus.
Most of the outcrops of Central Park are roche moutonnée that were cut by a thick ice sheet into bedrock during the Pleistocene. Glacial polish and striations are clearly visible.
The large outcrop near 59th Street is a biotite-muscovite-garnet-plagioclase-sillimanite schist that is intersected by common pegmatites and amphibolite layers that are approximately conformable to the rock foliation.
Please note the mineralogy and texture of this rock because we will compare it with outcrops from further north into Central Park and elsewhere on the trip. But please be mindful of the time and try not to wander too far north into the park.

STOP 2. Riverside Park (Boat Basin)
The outcrops near 82nd Street just north east of the Boat Basin have been described as Cambrian Hartland Formation by Schuberth (1967), (Fig. 1); as Cambrian-Ordovician Hartland Formation by Baskerville (1994), Fig. 2); as Cambrian-Ordovician Hartland Schist by Merguerian and Merguerian (2004), (Fig. 3); and as Ordovician Pelham Bay-Type Hartland Formation by Brock and Brock (2001), (Fig. 4). The exact outcrop location appears on the map by Baskerville (1994) and includes strike and dip data as do all of his outcrop locations.

STOP 3. City College Campus and St. Nicholas Park (lunch)
Box lunches will be provided for all that have ordered them. While you are eating please examine any of the excellent exposures of Manhattan Schist throughout St. Nicholas Park adjacent to the campus of The City College but please don’t wander too far off.
There is a general consensus that the outcrops exposed on the campus of the City University of New York (The City College) and along the St. Nicholas Park hill-side adjacent to the campus are Manhattan Schist (Figs 1-4). Samples observed here can, therefore, be thought of as a Manhattan Schist standard for comparison with other field trip stops.
St. Nicholas Avenue at the base of St. Nicholas Park marks the boundary between the Manhattan Schist on the west and the Inwood Marble on the East. The topography marking the highlands, locally Sugar Hill, has long been considered the result of differential erosion that sculpted the softer marble unit at the base. However, the downward-stepping outcrops that can easily be traced in the Park may represent an imbricate structural system that down-drops the schistose unit eastward.

STOP 4. Pelham Bay (Bronx, NY) Park in Beach Parking Lot
Walk to north end of the beach and outcrops are at shoreline at Latitude 40.870095°; Longitude -73.783833°
The structural geology and petrology of Pelham Bay Park has been described by Seyfert and Leveson (1968). They used the New York State geological map by Fisher et al. (1961) as their source of stratigraphy which had designated the Pelham Bay rocks as "…undivided schists and gneisses of unknown age". Seyfert and Leveson (1968) divided the Pelham Bay rocks into a "Felsic Unit" consisting of felsic quartz-plagioclase-biotite-gneisses and biotite-sillimanitic schists and a "Mafic Unit" consisting of amphibolites, plagioclase-biotite gneiss and minor calcite-rich layers and plagioclase-rich layers. They also describe several pegmatites within both units.
Some of this wide range of lithologies including pegmatites, pegmatite border zones, and the unusual calcite-rich layers were chemically analyzed with accompanying mineral modes (Seyfert, 1968). However, about 85% of their map of Pelham Bay Park consists of the "Felsic Unit". It is difficult to determine which lithology typifies the Felsic Unit but seems to fall somewhere close to an undefined boundary between schist and gneiss. In general the Felsic Unit is largely a biotite- plagioclase-quartzsillimanite-muscovite-garnet rock that mineralogically overlaps most of the schists of Manhattan. Microcline is notably absent or only a minor component of most of the rock but is a major component of some of the pegmatites. The microcline rich pegmatites appear to be discordant intrusions that intersect the foliation of the host rocks. A plagioclase rich generation of pegmatites is approximately equally common but is generally concordant to the foliation of host rocks that are also plagioclase rich and depleted in microcline.
Chemical analyses of the felsic unit members including plagioclase-biotite gneiss containing 64 % plagioclase and 35 % biotite and sillimanite schist containing 27 % plagioclase 43 % biotite and 11.5 % sillimanite (Seyfert, 1968) appear in Table 4.
Most of the exposed rock of Pelham Bay is a lighter shade of gray and not as reddish compared to Manhattan Schist. However, we find that fresh broken surfaces are difficult to distinguish from Manhattan Schist and are equally difficult to distinguish petrographically in thin section. We therefore invite all field trippers to carefully compare Pelham Bay rock with Manhattan rock. If any of you find any consistent mappable distinctions please share them with the rest of us.
One possible distinction may be contrasting plagioclase/biotite ratios. In general the plagioclase/biotite ratio of the average Pelham Bay rock is higher than typical of the schists of Manhattan. This elevated ratio is reflected in the contrasting (although overlapping) Na/K ratio of the analyzed rocks (Fig. 6). The plagioclase/biotite ratio may, therefore, be one of the few ways to map Hartland/Manhattan boundaries although, again, overlapping values do not permit definitive conclusions. As previously stated, sodic enrichment is an important characteristic of calc-alkaline lithologies such as the andesitic volcanicarc lithology proposed for the protolith of the Hartland Formation.

6: RESULTS (OR CONSEQUENCES) OF REMEDIATION AT LEMON AND MILL CREEK SITES, STATEN ISLAND, NEW YORK
Peter G. Crowley and William G. Wallace
Department of Biology
College of Staten Island
2800 Victory Boulevard
Staten Island, NY 10314
Lemon Creek and Mill Creek are two sites impacted by metals contamination. (See Figure 1.0) Both locations share common history in that they were active industrial sites for over one hundred years. Manufacturing operations ended at both locations and the buildings demolished. Development plans for the sites are still pending.
The S.S. White Dental Supply Company factory was located near Lemon Creek on the southern shore of Staten Island facing Raritan Bay. This facility manufactured dental instruments and amalgams from 1937 to 1986. Suspected contaminants include copper, lead, zinc, and mercury.
Mill Creek (AKA Nassau Creek) is a small tidally flushed creek located 3 km from the opening of the Raritan Bay. It is located adjacent to a facility that was previously used to recover metals from old telephone transmission cables. This facility closely resembled a smelting operation. The Tottenville Copper Company was located adjacent to Mill Creek in 1900. By 1941, the plant was operating as the Nassau Smelting and Refining Company. In 1971, it became the Nassau Recycling Corp where copper, lead and zinc were recovered from old telephone cables. This creek received effluent from the smelting facility for approximately 40 years (the mid 1930’s through the late 1970’s). As a result, the site received a Superfund designation for contamination. (EPA ID: NYD086225596)
The Mill Creek site is located on the western shore of Staten Island facing New Jersey. Mill Creek is located along the Arthur Kill Waterways known for frequent oil discharges by passing vessels.
For more than a century, chronic pollution from industrial facilities along the Arthur Kill has severely degraded its water quality (Crawford, etal., 1994). Furthermore, anthropogenic pollution has caused the fertile marshlands to deteriorate. Due to the potential toxicity and transference up the food chain, chemical pollution continues as a major concern in coastal ecosystems (Goto, Wallace, 2010).
Remediation efforts were conducted at both locations in 2000. These efforts consisted of removing contaminated soil. Both sites are still under investigation to determine the present contamination levels.
Live worms and grass shrimp samples were collected at both sites in 2007. Tissues obtained from these samples were used to compare body burdens of metals before and after remediation.
Shrimp and worms are used to assess the biological health of a wetlands site where contamination is suspected. Worms collected for this study live amidst the contaminated sediments. Shrimp live higher in the water column and are relatively mobile. Shrimp and worms take up pollutants internally during normal feeding. Once digested the pollutant is retained in tissues. Animals higher in the food chain have the ability to "accumulate" toxins by eating contaminated prey.

6: RESULTS (OR CONSEQUENCES) OF REMEDIATION AT LEMON AND MILL CREEK SITES, STATEN ISLAND, NEW YORK

STOP 1. Mill Creek
Mill Creek is located near the confluence of the Arthur Kill and the Raritan Bay has been polluted from historic smelting activities. The Tottenville Copper Company, a metal processing plant was established adjacent to Mill Creek in 1900. By 1941, the plant was operating as the Nassau Metals and Refining Company. Thirty years later the plant was renamed the Nassau Recycling Plant whose chief purpose was to recycle copper and zinc from old telephone cables.
Mill Creek runs through the property formerly occupied by the metals smelting and refining plant. The location is less pristine than the Lemon Creek site chosen for this tour. Our viewing site will be on Arthur Kill Road looking west toward New Jersey. (40˚31’12.15"N; 74˚14’23.24"W from Google Earth) The Arthur Kill, a 25-mile long tidal strait, runs northeast to southwest from Newark Bay to Raritan Bay and separates Staten Island from New Jersey. Despite improvements in recent years, levels of trace metals and PCB’s in some sediment remain high. Accidental discharge of petroleum products into the Arthur Kill is a chronic problem due to the number of oil transfer facilities. Although major oil spills occur infrequently, many small oil spills occur each year. These events are compounded due to the low flushing and increased residence time of water. Urban runoff containing petroleum products also adds to the burden on this system. Mill Creek is a typical marsh within the Arthur Kill system. Mill Creek is located just south of the Outerbridge Crossing on the New York side.

STOP 2. Lemon Creek
This site is located just northeast of the light tower in Figure 2.1 inside Lemon Creek Park’s 77 acres of narrow oak filled slopes that surround a sizable tidal marsh area. The creek and salt marsh represent the last remnants of a wetland system that flows through Bloomingdale Woods. Lemon Creek is one of a few relatively undisturbed tidal marshes on Staten Island. Our viewing site will be on a bridge on Hylan Boulevard, which runs across Lemon Creek. (40˚31’03.66"N; 74˚12’04.01"W from Google Earth).