NYSGA 1978
NEW YORK STATE GEOLOGICAL ASSOCIATION
GUIDEBOOK
50th Annual Meeting
SYRACUSE, NEW YORK
23-24 September 1978
Daniel F. Merriam, editor
Department of Geology
Syracuse University
INTRODUCTION
It is appropriate that the Golden Anniversary meeting of the NYSGA be held at Syracuse University. Syracuse has been involved actively in Association activities since the beginning. As secretary, Harry N. Eaton of SU issued the announcement of the first meeting to be held at Hamilton College in April of 1925. He then was president the next year as Syracuse served as host.
In 1937 SU was host for the 13th meeting with Louis W. Ploger president. Again in 1950 Ploger served as president as Syracuse hosted the 22nd annual meeting on the Silver Anniversary of the formation of the Association (1925-1950). John J. Prucha organized the 36th meeting in 1964.
Syracuse is always proud and pleased to host the Association that may be the oldest organized state intercollegiate geological group in the country. The Association has grown considerably in size and stature from that first meeting 53 years ago (see paper by Lowe and Wolff on history of the Association in this volume). There is no record of the number of attendees but the meeting consisted of a few pages of handouts for the one field trip following a previous evening dinner and lecture. This loose organizational arrangement was successful in the early years and continued until 1953 when Kurt E. Lowe was elected first permanent secretary of the Association. The secretaryship provided a stability and continuity needed for the Association and beginning in 1956 guidebooks for each meeting were kept in print for sale. Lowe was followed in office by Philip Hewitt in 1968 (now the office was termed executive secretary), D.F. Merriam in 1972, and Fred Wolff in 1977. The Association affiliated with the American Association of Petroleum Geologists in 1974.
The Association grew in permanency and organization (it now had a constitution) so did the size of the guidebooks. From a few pages in 1925 to 425 pages in 1977. Subject matter was expanded until today the guidebooks provide one of the most important sources of information on the geology of New York State.
The offerings this year are no exception. In addition to write ups and roadlogs for the 17 trips, background papers on selected subjects are included. Of special importance are the two papers on the history of geology in New York by Don Fisher of the NY State Geology Survey and on the history of the Association by Kurt Lowe and Fred Wolff. These contributions undoubtedly will serve as standard references for years to come.
Each of the authors are to be thanked for their contribution. It is their collected efforts that made this publication possible. A different procedure was used this year on preparing the papers for inclusion in the guidebook. Each author was asked to provide finished copy for direct reproduction. Although this method has its problems (but all publication methods do), it allows authors greater flexibility and the possibility to make last minute changes. It also speeds up production time and reduces costs.
Many people have cooperated in putting on this meeting. Janice Patak assisted in typing, editing, and proofreading material for the guidebook and helped in a variety of other ways. Beverley O'Brien and Debby Blose also have assisted in preparing material and making arrangements. All of the faculty and students of the Department of Geology at SU have given considerable time and effort in preparing for the meeting. Credit for success of the meeting goes to the entire Department.
Dewey Hale of the Syracuse Chamber of Commerce provided material and advice in making arrangements. Owen Muir of the Treadway Inn helped with the housing. Elmer Foote of the SU press assisted with the printed material. Many individuals and other Departments at Syracuse University cooperated in the logistical arrangements.
Last but not least Fred Wolff lent his support for the entire year of preparations. This was most appreciated.
So here are the results for the golden anniversary volume. May the next 50 years of the Association be equally successful and rewarding to those involved and interested with the geology of New York State.
D.F. Merriam, President
New York State Geological Association
Syracuse, NY 13210

A1: DEFORMATION STRUCTURES IN LOWER PALEOZOIC ROCKS, NORTHWESTERN NEW YORK
Brian G. Barber and John T. Bursnall
Department of Geology
Syracuse University
Syracuse, NY
INTRODUCTION
This field trip is concerned with the nature and origin of some deformation structures within lower Paleozoic cover to Precambrian basement in the vicinity of Theresa, New York (Fig. 1). Many of the structures suggest localized mobility within the basement that generated instability within the cover rocks - both during and at some time following their deposition.
All of the main stops will be within the Potsdam Sandstone (Upper Cambrian) and the Theresa Formation (lower Ordovician). A cursory examination of some of the Precambrian gneisses also will be made.
The Potsdam Sandstone in the Theresa area lies with marked angular unconformity on a Precambrian sequence of marble and quartzo-feldspathic gneisses. The sub-Potsdam surface in places is rugged with a relief in excess of 70 ft although some of this relief may be due to penecontemporaneous faulting during sedimentation (Stops 2 and 3). The relict topography in part may be due to differential erosion of alternating zones of marble and quartzo-feldspathic gneisses because in some areas the marble underlies marked topographic depressions. Where observed, the lowermost Potsdam occurs above an approximately 3-ft thick weathered zone of the basement rocks (Barber, 1977). The Potsdam Sandstone in this area typically consists of a buff to light-gray, thin-bedded to massive, silica-cemented, medium-to fine-grained orthoquartzite; minor amounts of detrital feldspar, mica, and tourmaline occur but rarely exceed 3 percent of the mode. It lacks the pink coloration of the lower parts of the formation in the north (Kirchgasser and Theokritoff, 1971; Selleck, 1978).
The irregular topography on the Precambrian profoundly influenced Potsdam sedimentation. Lowermost Potsdam rocks occur in depressions of the basement surface and these areas are characterized by syndepositional deformation structures. Rapid and large changes in thickness, breccia slides, and minor faulting suggest active faulting during deposition (Stops 2, 3 and 5). At least one of these areas is on strike with NE-trending faults within the basement to the north (R.V. Guzowski. 1977, pers. comm.; Barber, 1977; Buddington, 1934).
The overlying lower Ordovician Theresa Formation ranges in composition between dolomitic limestone to quartz sandstone, the latter being concentrated in the lower 5 to 10 ft of the formation (Stop 1). Calcite sandstones locally occur within the succession. Typically, the Theresa is thinly bedded and light gray. Convolute lamination is a locally abundant feature.
In the central part of the area (Fig. 1), Theresa limestones outcrop as outliers capping elongate low-amplitude domal folds. These are best observed within a 3-5 mi wide NNE-trending zone extending from Perch Lake in the south to Butterfield Lake in the northern part of the area. The boundaries of this zone are marked imprecisely by NNE-striking probable fault zones within the basement. The effect of these on the Potsdam-Theresa sequence is seen as instability during sedimentation in the east
(see previous discussion) and in post-depositional folding throughout the zone. The latter is particularly well developed in the central and western parts of the zone within the structurally higher Theresa Formation.
Fold-producing post-Ordovician deformation has been described from the succession to the north, in the St. Lawrence Valley (Chadwick, 1915) and post-Potsdam mineralization along veins and joints throughout the region close to the contact with the Precambrian attests to Phanerozoic thermal reactivation of parts of the basement (B.W. Selleck, 1978, pers. comm.). This may have been accompanied by major faulting that deformed the overlying cover. No faults of regional extent have been observed to cut the cover rocks in the Theresa area (Barber, 1977).

STOP 1. Junction Rt I-81 and Rt NY 411
The lowermost part of the Theresa Formation is exposed on both Sides of this road cut in the hinge zone of an elongate, NE-trending dome (Fig. 2). It is typical of many of the upright to steeply inclined gentle anticlinal folds in the region that occur as relatively high ground separated by broad synclinal or undeformed rock underlying the intervening low and usually poorly drained ground. This 'first order' topography is characteristic of the western and central parts of the area. The fold trends N33°E, and the hinge line plunges NE at approximately 12° at this locality. The interlimb angle is around 160 and no measurable layer thickness variation occurs across the fold.
To the south the hinge-zone widens and extends for at least a mile. Minor folds are present in a relatively flat-lying axial zone.
Three recognizable but dispersed joint sets traverse the fold with mean trends of N74°E, N46°E, and N50°W (Barber, 1977). Probably only the N46°E set is related directly to folding because on rotation of the beds to the horizontal their poles develop a tight zero plunge cluster whereas the remaining two sets become more dispersed. On the northwestern limb, joints of this set dip steeply to the southeast whereas on the southeastern limb, dips are steeply to the northwest; they probably are extensional 'ab' fractures developed during the folding process. The N74°E and N500W post-date folding.
Other features at this locality include: low-angle joints striking NE within the hinge zone suggesting a compressional origin for at least parts of the fold; and a calcite-pyrite mineralization in places occurring along joints of the N74°E set.
The origin of the folds of the type represented at this locality is enigmatic. They are, however, unlikely to be syndepositional and a glacial origin is not convincing because glacial striae throughout the area do not hold any systematic relationship to fold trends. The present evidence indicates a tectonic origin, either as localized deformation within the Lower Paleozoic rocks resulting from faulting within the basement or from concentration of strain at abrupt changes in relief, and therefore a probable thickness variation in the Potsdam Sandstone. Relatively high strain at the Potsdam-Theresa boundary or within the transitional zone between the two lithologically distinct formations has not been supported by the limited observations possible at this stratigraphic level. The regional shortening required for such low-amplitude folds is extremely small.
A comparison with a fold of known glacial origin (Stop 5A) will be made following Stop 5.

STOP 2. English Settlement Road
Exposures are of Potsdam Sandstone typical for this area (Fig. 3). Hematite staining has accented crossbedding, minor slump structures and small-scale lamination. In some occurrences, however, the staining is independent of any internal structure and may be described as 'liesegangbanding'.
Bedding is folded in a manner typical of the lower part of the Potsdam Formation. Hinge lines are tenuous and variable in orientation, and individual beds thicken and thin greatly through short distances. The most obvious fold at this locality is one of a series of irregular gentle undulations of bedrock, between which are small areas underlain by Grenville rocks or horizontal Potsdam strata. The hinge-line of the fold trends approximately N40°E. Other folds in the area exhibit a similar trend wherever hinge lines can be determined accurately (Fig. 3).
The railroad cut transects the southern end of the fold at an oblique angle, and expresses a hinge-zone as well as the northwestern limb. The central part of the fold is comprised of horizontally bedded Potsdam and shows no evidence of deformation. On the limb, however, are a number of features indicative of pre-induration deformation. Approximately 10 ft from the northern end of the outcrop, a massive sandstone layer abruptly deflects downwards and terminates against an adjacent underlying layer. Overlying layers exhibit annealed fractures and lumpy, contorted bedding as they form a flexure over the zone. The flexure has been propagated to the top of the exposure.
Strata to the south, for a distance of approximately 65 ft, form the fold limb, which dips between 5° and 10° toward the northwest. The sandstone is cut by fractures, some of which are differentially weathered normal faults of small displacement (usually less than 0.5 in) that dip to the northwest. Some of these are filled with granular quartz.
On the limb, beds pinch and swell and may change from massive to shaly character through distances of 10 ft or less. Most crossbedded layers are thin and crossbeds are planar.
A major slump structure occurs near the fold crest (partially obscured by a pine tree). At the lower part of the outcrop, a portion of a large slump block is exposed. Poorly layered sandstones within and adjacent to the block are separated by a narrow zone of homogeneous disturbed sandstone.
The abundance of features indicative of soft-sediment deformation suggests that these folds, which generally occur adjacent to topographic highs of the basement, formed by rapid downslope movement during and closely following sedimentation.

STOP 3. Theresa Village
This outcrop is located on the Theresa side of the Rt NY 26-411 bridge over the Indian River. At the cliff face on the south side of the road, Potsdam Sandstone overlies an exposure of weathered basement gneiss. The effects of initial dip are evident here as the Potsdam offlaps a knob of Precambrian rock. Irregular bedding, numerous minor unconformities and evidence of soft-sediment deformation characterize the outcrop. Where the Precambrian core has been eroded, ripples are exposed within the Potsdam that probably formed as a result of slow downslope movement of unconsolidated sediment.
Large slump blocks are exposed in the cliff face adjacent to the sidewalk. Each block is set in a matrix of sandstone that exhibits small-scale contorted laminae or is accented by hematite. The interface between block and matrix tends to be sharp, and suggests slumping of partially consolidated sediments in areas of steep paleoslope.

STOP 4. Ritchie's Farm
The high ground behind the farm buildings is comprised of variably bedded, buff-colored, lower Potsdam Sandstone that forms a broad structural basin toward the north. It is typical of all the outliers of Potsdam Sandstone in the region and its relationship to underlying Grenville. Whether this and other basins of similar type are primary is uncertain. Calculations of thickness variations in individual beds is not possible through lack of exposure.
The dominant joint sets in the Potsdam at this locality are nearly vertical and trend N42°W and N81°E, whereas those in underlying Grenville gneiss trend between N42°E and N66°E and dip southeast between 57° and 70°. The strike of these joints tends to be parallel to the strike of the main foliation, whereas dip of these same joints tends to be perpendicular to the foliation. The foliation in coarsely crystalline quartz-biotite-plagioclase (?oligoclase) gneisses, visible a few yards downhill from the Potsdam contact, strikes N68-84°E and dips northwest between 39° and 43°. This trend is consistent for all exposures of Precambrian rock adjacent to this and other nearby outcrops.

STOP 5. North of Redwood, Rt NY 37
A major basement fault with relative displacement down to the northwest is inferred to underlie the valley immediately west of the hill (Fig. 4). The hill is comprised of a structural basin containing Potsdam Sandstone similar to that at the previous stop. At the roadcut. Potsdam beds strike N41°E and dip gently southeast. They consist of both evenly and irregularly bedded sandstone containing "liesegang" type banding, conglomeratic zones and numerous soft sediment deformational structures. A large cone-shaped concretion of the type described by Dietrich (1953) is well exposed in the outcrop. The structure seems to consist of a cone within a cone, with the axis of the inner cone being somewhat offset from that of the larger, outer cone. The angular relations between bedding planes and sides of the outer cone, which is approximately 7-8 ft in diameter at the top of the outcrop, indicate that the cone may have been tilted concurrently with tilting of the bedding. Therefore, rotation of the Potsdam beds followed at least partial compaction and lithification. Dietrich ascribed the formation of these structures to slumping of semi-consolidated sands into solution cavities in underlying Grenville marble. Within and along the margins of the structure, the sandstone is chaotically bedded, and contains numerous healed fractures and small slump blocks. These conical or cylindrical structures occur elsewhere in the area, and although they suggest the importance of soft-sediment deformation, this is the only one that occurs in tilted strata.

A2: THE STRUCTURAL FRAMEWORK AND PETROLOGY OF THE SOUTHERN ADIRONDACKS
James McLelland
Department of Geology
Colgate University
Hamilton, NY
Ennis Geraghty
97B Shafer Road, Apt. 1B
Albany, NY
with a section on Ledge Mountain by
Gary Boone
Syracuse University
Syracuse, NY
INTRODUCTION
The area referred to as the southern Adirondacks is shown in Figure 1. Within this region, the Precambrian is bounded approximately by the towns of Lowville and Little Falls on the west and Saratoga Springs and Glens Falls on the east.
Mapping in the southern Adirondacks was done first by Miller (1911, 1916, 1920, 1923), Cushing and Ruedemann (1914), Krieger (1937), and Cannon (1937); more recent investigations were undertaken by Bartholomew (1956), Thompson (1959), Nelson (1968), and Lettney (1969). At approximately the same time Walton (1961) began extensive field studies in the eastern portion of the area (Paradox Lake, etc.), de Waard (1962) began his studies in the west (Little Moose Mt. Syncline). Subsequently de Waard was joined by Romey (de Waard and Romey, 1969).
Separately and together, Walton and de Waard (1963) demonstrated that the Adirondacks are made up of polydeformational structures, the earliest of which consist of isoclinal, recumbent folds. Their elucidation of Adirondack geology set the tone for future workers in the area. In this regard one of their most important contributions to the regional picture was that the stratigraphy of the west-central Adirondacks is correlative with that of the eastern Adirondacks.
Beginning in 1967 McLelland (1969, 1972) initiated mapping in the southernmost Adirondacks just to the west of Sacandaga Reservoir. This work was extended subsequently north and east to connect with that of Walton and de Waard. Geraghty (1973) and Farrar (1976) undertook detailed mapping in the eastern half of the North Creek 15' quadrangle. This tied into investigations in the Brandt Lake region by Turner (1971). Recently, Geraghty (1978) completed a detailed study of the structure and petrology in the Blue Mt. Lake area. The foregoing investigations have increased our knowledge of the southern Adirondacks, and this field trip is designed to show as many examples of the region's structure, lithology, and petrology as time allows.

A2: THE STRUCTURAL FRAMEWORK AND PETROLOGY OF THE SOUTHERN ADIRONDACKS

STOP 1: Large roadcut on north shore of Lake Durant.
This location is the type section of lake Durant Formation (D. de Waard, 1970, pers. comm.).
This stop has been described by de Waard (1964b) as follows: "The section of diverse, layered metamorphic rocks includes pink and greenish leucocratic gneisses with thin metabasic layers, marble, and calc-silicate rocks. The section forms part of the supracrustal sequence which overlies the leptites of the Wakely nappe exposed in the hills visible towards the south across the lake. and which underlies the Blue Mountain charnockite sequence towards the north. Lineations on foliation planes indicate a 30° NE plunging fold axis. The intrusive nature of marble into boudinaged layered gneiss is shown on the west end of the north side of the read cut."
Outcrop mapping to the east and south has revealed that the Lake Durant Formation contains large amounts of hornblende granitic gneiss and biotite-hornblende granitic gneiss both above and below the well-layered sequence exposed in the type section at Lake Durant. In addition, a distinctive rock sequence of biotite granitic gneiss (bottom), calc-silicate rock, and platy-quartz gneiss (top) makes up the basal portion of the Lake Durant Formation in areas to the south.

STOP 2.: Ledge Mt.
Hike 1 mi east through open woods, to well-exposed south-facing cliffs. This is on the southward culmination of the recumbent Ledge Mountain antiform. Quartz-sillimanite lenses increase in size and relative amount from west to east. until they assume the proportions of major layering in the gneiss. Kyanite occurs here in two feldspar-rich portions of the gneiss. We have sought more, without success. If you should discover additional kyanite, PLEASE OBSERVE PETROLOGIC ETIQUETTE OF PHASE PRESERVATION: NOTIFY TRIP LEADER, WHO WILL OFFER SUITABLE REWARD. Note different proportions of magnetite, garnet, and biotite in feldspathic portions of gneiss, as well as in pegmatite. The structural relationships of pegmatite to host gneiss also differ. Note in Figure 21A that biotite compositions within garnet porphyroblasts are Mg-richer and Al-poorer than "Free" matrix biotite. Also, of the four plagioclase-garnet equilibria shown in Figure 21B (representing five pairs), all represent 'probed rims of grain pairs each of which is in mutual contact. The highest-P boundary is that calculated for a relatively large plagioclase grain within a garnet porphyroblast; the others are of small plagioclases within garnet porphyroblasts, and of "free" plagioclases against garnet rims.
It is deduced from these relationships. and from ubiquitous but small-scale late corona structures of albite on magnetite, that the path of P-T change was prograde along a geothermal gradient which penetrated the kyanite field, followed by partial melting and decrease of lithostatic pressure into the sillimanite field and retrograde cooling within that field, with residual kyanite being trapped within feldspar-rich (solidus?) portions of the gneiss.

STOP 3: Scenic overlook on E side of Route NY 30.
Mountainous area to the southeast is part of the Thirteenth Lake complex, cored by anorthosite and charnockite. Overlying gneisses dip to the north (left) and west (towards us) off the complex. To the south metasedimentary rocks dip to the northeast off of Snowy Mountain dome (not visible), which also is cored by anorthosite and charnockite.
Walk south on highway NY 30 to roadcut on west side of road. This roadcut is composed of a distinctive "diopside-clot" gneiss and is situated close to the axial core of the Crow Hill synform. The rock is a zircon-apatite±plagioclase±calcite±garnet-sphene-scapolite-clinopyroxene-quartz-microcline granulite. It is part of the distinctive basal portion of the Lake Durant Formation.
Chemical compositions of scapolite and clinopyroxene from this unit at another location were determined by electron-probe microanalysis to be Me69, and salite, (CaO.93,NaO.06)0.99(M90.62,FeO.39,MnO.Ol,Al0.02)1.04(Si1.96 Al0.04)2O6, respectively. Plagioclase composition is oligoclase, An21, based on petrographic determinations using the zone method of Rittman.

STOP 4: Anorthosite-charnockite suite of rocks
Described by de Waard (1964) as follows: "Large road-cut on the hill 0.4 miles southwest of the intersection of highway 30 with the lake shore road through Sabael. Anorthosite at the lower end of the outcrop is overlain by metanorite (unfoliated andesine-pyroxene-hornblende gneiss) which is in turn overlain by streak andesine-pyroxene-hornblende augen gneiss. Both "Marcy-" and "Whiteface-" type anorthosites are present. The grain size of metanorites ranges from coarse to fine, and the original texture of the rock is preserved to various degrees in different parts of the exposure. Several small amphibolite (metadolerite) lenses may be observed in the streak gneiss. Foliation is nearly horizontal. Walk up the steep hillside above the road to see massive ledges of anorthosite, metanorite, and a rock which is texturally and compositionally intermediate between these two types."
The origin of, and relationships within, the anorthosite-charnockite suite of rocks has been debated for decades. Those favoring a comagmatic association have tended to postulate a dioritic parent magma which yields plagioclase (anorthositic) cumulates and charnockitic residua (de Waard and Romey, 1969). Those who do not accept a comagmatic relationship between these rocks, have generally postulated a parent of gabbroic anorthosite composition (Buddington, 1972). A variant of the gabbroic anorthosite parent is the high-alumina basalt of Morse (1975).
The snowy Mt. Dome is the type area of de Waard and Romey's (1969) comagmatic differentiation process. By detailed mapping beginning at the core of the dome, they showed that there exists an outward gradation from central anorthosite through metanorite, to noritic augen gneiss, to charnockitic gneisses (see Fig. 22). This they interpreted as reflecting a differentiation sequence and variation diagrams were constructed to portray these trends.
A critical aspect of the compositional variation within this suite is that grains (xenocrysts) of andesine occurs within the charnockitic rocks. These xenocrysts increase in abundance as the anorthositic core rocks are approached. Concomitantly the amount of K-feldspar and quartz decrease. Although these changes do result in a gradation of rock types, the transition seems to be mechanical rather than chemical. This is suggested by the constancy of xenocryst composition and the widespread presence of cross-cutting relationship between end-member rock types.
Based upon field and chemical data Buddington (1939, 1972), suggested that the charnockitic rocks are distinctly later than, and unrelated to, the anorthositic rocks. He presented variation diagrams of major oxides demonstrating that the anorthositic and charnockitic rocks follow separate differentiation trends and that discontinuities exist between their paths. Simmons (1976) and Goldberg (1977) have studied trace element and REE patterns in Adirondack anorthosite-charnockite lithologies and concur with Buddington that the two are unrelated. They also show that a gabbroic anorthosite parent is consistent with their trace-element studies. Simmons suggests that such a parent can be produced from dry melting at high load pressure of a gabbroic source rock. Figure 23 shows Emslie's (1971) results for such a system at P = 15 Kb and at 1 atm. The minimum melt generated at 45-50 km is essentially a gabbroic anorthosite. As it rises the field boundaries move so as to enlarge the domain of plagioclase crystallization. In this manner anorthosites may result from reasonable petrogenetic processes.
The origin of the charnockitic rocks in the suite remains largely unresolved. Buddington (1972) suggests that they represent an independent magma series in which contamination of granitic magma by garnetiferous amphibolite has been important. Husch, Kleinspehn, and Mclelland (1975), as well as Isachsen, McLelland, and Whitney (1975), have suggested that the charnockite-mangerite envelope results from fusion of quartzo-feldspathic country rocks of the intruding anorthositic magma (crystal mush ?). Early in the process the anorthositic rocks attain complete crystallization and are subsequently intruded by the lower melting temperature quartzo-feldspathic lithologies. Wiebe (1975) has suggested a similar mechanism for adamellites near Zoar (Nain), labrador. All fusion models of this sort depend critically on the initial temperature of the charnockitic rocks and the heat budget within the system. Although the lack of data on heat capacities, heats of fusion. etc. preclude detailed calculations, it does seem possible that at 8-10 Kb anorthositic intrusives with temperatures of 1200-1300°C can melt substantial quantities of quartzo-feldspathic gneisses initially at 800°C. Whether or not this mechanism actually operates is a question deserving of extensive research. It is certainly consistent with field evidence suggesting that stratigraphically continuous units undergo increasing anatexis as anorthositic rocks are approached. Some examples of this anatexis will be seen at Stop 7.

Charnockites of the Snowy Mt. Dome.
These type "a" quartzo-feldspathic gneisses tend to be more massive than charnockites higher in the sequence. They also contain xenocrysts of andesine. de Waard and Romey (1969) believed that these charnockites were comagmatic with the anorthosites of the Snowy Mt. Dome. Buddington (1963) has argued that they are later than the anorthosites. Isachsen, McLelland, and Whitney (1975) suggested that these, and similar, charnockites are the products of melting accompanying intrusion of the anorthosites into quartzo-feldspathic country rocks. Rb/Sr whole rock ages obtained by Hills and Isachsen (l975) yield results of ˜1.2 by and do not suggest that these charnockites are part of an "older" basement complex.

Lake Durant Fm. and the Lower Marble
The lower Lake Durant Fm. and the Lower Marble are exposed in this general vicinity.

Contact of the Lower Marble with the Lake Durant Fm.

Contact of the Lake Durant Fm. with the Upper Marble.

Passing through thick charnockite layer in the Upper Marble.

Passing through units of the Upper Marble.
Generally low dips have resulted in broad exposure of this unit. Note horizontal foliation in some roadcuts.

Cross contact with Blue Mt. Fm
Cross contact with Blue Mt. Fm. which cores a local F2 syncline.

Contact of Blue Mt. Fm. with Upper Marble.
Passing into the southern limb of the F2 syncline.

Garnetiferous amphibolite in Upper Marble
Long roadcuts of garnetiferous amphibolite in Upper Marble. Some garnets attain diameters of 5-6", A large pegmatite is also present. Note that this outcrop sits astride the hinge line of an F2 anticline.

Contact of Upper Marble amphibolites and Blue Mt. Fm.

Charnockites of Blue Mt. Fm.

Cross into Upper Marble

STOP 5. 3.3 miles east of Speculator, New York.
The Upper Marble Fm. is exposed in roadcuts on both sides of the highway. These exposures show typical examples of the extreme ductility of the carbonate-rich units. The south wall of the roadcut is particularly striking, for here relatively brittle layers of garnetiferous amphibolite have been intensely boudinaged and broken. The marbles, on the other hand, have yielded plastically and flowed with ease during the deformation. As a result the marble-amphibolite relationships are similar to those that would be expected between magma and country rock. Numerous rotated, angular blocks of amphibolite are scattered throughout the marble in the fashion of xenoliths in igneous intrusions. At the eastern end of the outcrop tight isoclinal folds of amphibolite and metapelitic gneisses have been broken apart and rotated. The isolated fold noses that remain "floating" in the marble have been aptly termed "tectonic fish." The early, isoclinal folds rotate on earlier foliation.
Features such as those seen within this roadcut have led this writer to question the appropriateness of assigning an unconformity to the base of the lower Marble Fm. Tectonic phenomena in rocks of high viscosity contrast can account for the fact that the marbles are able to come into contact with a variety of lithologies.
A variety of interesting lithologies are present in this roadcut. The marble itself contains diopside (now serpentinized), tremolite, tourmaline, graphite, sphene, phlogopite, and a variety of pyrites. Interesting reaction rims, or selvages, exist between the marbles and quartz-rich boudins. Presumably these selvages reflect the influence of compositional gradients during metamorphism. Quartz and calcite coexist in these rocks, and wollastonite is not known to occur at this location.
Most of the amphibolites in the outcrop are highly garnetiferous and some layers seem to contain 60-70 percent garnet. The garnets are almandine-rich and are similar to those at Gore Mt. However, it is not known whether these amphibolites represent metamorphosed sedimentary or igneous rocks. Note that a number of the garnets are separated from surrounding hornblende by narrow light colored rims. These consist of calcic plagioclase and orthopyroxene and represent products of the reaction:
Garnet + Hornblende = Orthopyroxene + Calcic Plagioclase + Water.
This reaction is characteristic of the granulite facies wherein the association garnet + hornblende is unstable (de Waard, 1965a, 1965b).
Also present in the outcrop are various layers rich in calc-silicates. One of these contains coarse, pale diopside crystals several inches across. Others consist almost entirely of green diopside. Tremolite also occurs in some layers. Rusty weathering, metapelitic units are rich in graphite, calc-silicates, and pyrite. Neither grossular nor scapolite seems to have developed here.
Near the west end of the outcrop a deformed layer of charnockite is well exposed. In other places the charnockite-marble inter-layering occurs on the scale of one to two inches.
Exposed at several places in the roadcut are striking, cross•cutting veins of tourmaline and quartz displaying a symplectic type of intergrowth. Other veins include hornblende and sphene-bearing pegmatites.
Usually included in the Upper Marble, but not exposed here, are quartzites, kinzigites; sillimanite-rich, garnetiferous, quartz-microcline gneisses; and fine-grained garnetiferous leucogneisses identical to those characterizing the Sacandaga Fm. These lithologies may be seen in roadcuts 0.5 mi to the south.
Almost certainly these marbles are largely of inorganic origin. No calcium carbonate secreting organisms seem to have existed during the time in which these carbonates were deposited (> 1 by ago). Presumably the graphite represents remains of stromatolite-like binding algae that operated in shallow-water, intertidal zones. If so, the other roadcut lithologies formed in this environment as well. This seems reasonable enough for the clearly metasedimentary units such as the quartzites and kinzigites. The shallow-water environment is much more interesting when applied to the charnockitic and amphibolite layers. The fine-scale layering, and ubiquitous conformity of these, strongly suggests that they do not have an intrusive origin. Perhaps they represent the metamorphosed products of volcanic material in a shelf-like environment. Such intercalation is now occurring in many island arc areas where shallow-water sediments cover, and in turn are covered by, ash and lava. Alternatively they may represent metasediments.

STOP 6: Core rocks of the Piseco Anticline.
Hinge line of Piseco Anticline near domical culmination at Piseco Lake. The rocks here are typical quartzo-feldspathic gneisses "a" such as occur in the Piseco Anticline and in other large anticlinal structures, for example Snowy Mt. Dome, Oregon Dome.
The pink "granitic" gneisses of the Piseco Anticline do not exhibit marked lithologic variation. Locally grain size is variable and in places megacrysts seem to have been largely granulated and only a few small remnants of cores are seen. The open folds at this locality are minor folds of the F2 event. Their axes trend N70W and plunge 10-15' SE parallel to the Piseco Anticline.
The most striking aspect of the gneisses in the Piseco Anticline is their well-developed lineation. This is expressed by rod, or pencil-like, structures. These may consist of alternating ribbons of quartzite, quartzo-feldspathic gneiss, and biotite-rich layers. In many instances these ribbons represent transposed layering on the highly attenuated limbs of early, isoclinal minor folds. Near the northeast end of the roadcut such minor folds are easily seen due to the presence of quartzite layers in the rock. Slabbed and polished specimens from this and similar outcrops demonstrates that these early folds are exceedingly abundant in the Piseco Anticline. Examination of these folds shows that the dominant foliation in the rock is axial planar to them. Similarly, layer transposition is related to flattening parallel to the axial planes of the early folds. The intersection of this axial plane foliation and compositional surfaces helps to define the strong lineation in the outcrop. Also present is an earlier foliation subparallel to the one associated with the visible folds. Again intersections between these foliations, compositional surfaces, etc., result in a strong intersection lineation. In addition to this a number of rod-like lineations are probably the hinge line regions of isoclinal minor folds which are difficult to recognize because of relative lithologic homogeneity. Lineation in the outcrop is intensified further by the fact the upright and relatively open F2 folds are coaxial with F1. Thus the intersection of the F2 axial planar foliation with earlier foliations results in a lineation parallel to the F2 trend. Moreover, F2 minor folds may be of the crenulation variety and their sharp hinge lines define a lineation in the earlier foliation. As described previously. a number of parallel elements combine to produce an extremely strong lineation in the Piseco Anticline. Past observers have remarked that the lineation appears to be the result of stretching parallel to the long axis of the Piseco Dome. However, the lineation is probably unrelated to "stretching" and is explained more realistically as an intersection lineation of planar fabrics. Moreover, the intensity of the lineation is more the result of the early recumbent folding and flattening than it is of the later, coaxial F2 Piseco Anticline.

Red-stained quartzo-feldspathic gneisses "a"
On both sides of Rt. NY 10 are red-stained quartzo-feldspathic gneisses "a" that have been cataclastized by a large N20E fault zone. For the next 5.5 mi we shall pass through a number of road-curves as Rt. NY 10 makes its way through the core rocks on the south limb of the Piseco Anticline.

Cross into the Sacandaga Fm.

Parking area on east side of highway.
The rocks here are quartzo-feldspathic gneisses believed to be part of the Sacandaga Fm.

STOP 7: Lake Durant and Sacandaga Fms.
Lake Durant and Scandaga Fms. intruded by anorthositic gabbros and gabbroic anorthosites.
These roadcuts are located on Rt. NY 10 just south of Shaker Place.
The northernmost roadcut consists of a variety of metasedimentary rocks. These lie directly above the Piseco Anticline and are believed to be stratigraphically equivalent to the Sacandaga Formation. The outcrop displays at least two phases of folding and their related fabric elements. These are believed to be F1 and F2. A pre-F1 foliation is thought to be present. Both axial plane foliations are well developed here. Several examples of folded F1 closures are present and F1 foliations (parallel to layering) can be seen being folded about upright F2 axial planes.
Farther to the south, and overlooking a bend in the west branch of the Sacandaga River, there occurs a long roadcut consisting principally of pink and light green quartzo-feldspathic gneisses belonging to the Lake Durant Fm. About half-way down this roadcut there occurs a large and impressive boudin of amphibolite and diopsidic gneiss. To the north of this boudin the quartzo-feldspathic gneisses are intruded pervasively by anorthositic gabbros, gabbroic anorthosites, and various other related igneous varieties. At the north end of the cut and prior to the meta-stratified sequences these intrusives can be seen folded by upright fold axes. They are crosscut by quartzo-feldspathic material.
Within this general region the lake Durant Fm. and other quartzo-feldspathic gneisses seem to have undergone substantial anatexis. This is indicated by the "nebular" aspect of the rocks. Good examples of this are seen in the manner in which green and pink portions of the quartzo-feldspathic gneisses mix. Note also the clearly cross-cutting relationships between quartzo-feldspathic gneiss and mafic layers at the south end of the roadcut. Here it seems that mobilized lake Durant is cross-cutting its own internal stratigraphy. Also note that the quantity of pegmatitic material is greater than usual. This increase in anatectic phenomena correlates closely with the appearance of extensive metagabbroic and metanorthositic rocks in this area. We believe that these provided a substantial portion of the heat that resulted in partial fusion of the quartzo-feldspathic country rock.

Excellent examples of anorthositic gabbros
Roadcut on west side of highway shows excellent examples of anorthositic gabbros intrusive into layered pink and light green quartzo-feldspathic gneisses. The presence of pegmatites and cross-cutting granitic veins is attributed to anatexis of the quartzo-feldspathic gneisses by the anorthositic rocks.

Fine-grained metagabbro on west side Rt. NY10.

Excellent roadcut in coarse anorthositic gabbro.
Ophitic to sub-ophitic texture well preserved. Garnets are sporadically developed and tend to be associated with coarse gabbroic pegmatites showing mineral growth perpendicular to contacts. Compositional layering may be primary.

Small cut in megacrystic granitic gneiss on east side of highway.

Begin half-mile of roadcuts
Begin half-mile of roadcuts exhibiting intrusion of quartzo-feldspathic gneisses by members of the anorthositic gabbro suite, several phases of which seem to be present and in cross-cutting relationships. Source metasedimentary areas may be xenoliths. Pods of megacrystic gneiss may be anatectic in origin.

Kennels Pond - Avery's Fishing Site.

Lake Catherine to east of highway
Lake Catherine to east of highway; metasediments intruded by anorthositic gabbros in roadcut on west.

Avery's Hotel on west of highway at top of hill.

STOP 8. Kinzigites
On the west side of Rt. NY 10 is a rounded roadcut consisting of typical examples of sillimanite-garnet-biotite-quartz-oligoclase gneisses (kinzigites). These rocks are widespread south of the Piseco Anticline and are thought to represent meta-pelites associated with a locally deeper sedimentary basin in this region. Throughout the Adirondacks kinzigites are rich in white pods and lenses consisting of perthitic feldspars, garnet, and quartz. These are believed to be anatectic in origin. These anatectic areas seem to pre-date F1. In places they exhibit the pre-F1 foliation. Locally they show "fishhook-like" terminations suggesting that they have been involved with substantial transposition.
The kinzigites at this locality have been intruded by anorthositic gabbro which may be seen at the north end of the roadcut. The gabbroic rocks seem to gently transect the earliest foliation but have been involved in all other deformations.
Towards the southern end of the roadcut several generations of minor folds may be seen together with their associated foliations. The earliest recognizable folds have near-horizontal axial planes where they are located on the hinge lines of the upright set of folds that dominates the outcrop. The older set seems to fold a foliation and is assigned to the F1 generation. This requires that the dominant, upright set with its steep foliation belongs to the F2 generation of folds. If this is so we note that the F2 -related axial plane foliation can be locally intense. There seem to be two generations of garnet within most kinzigites. One may be flattened in the plane of foliation and may have formed by an amphibolite facies reaction similar to:
biotite + muscovite + quartz ----> garnet + K-feldspar + H2O
(Engel and Engel. 1962). The later generation of garnets grow across foliation planes and in several areas form coronitic rims around sillimanite. These garnets are believed to result from a reaction of the following type:
sillimanite + (Fe,Mg,Ti)Biotite + Quartz-> (Fe,Mg)Garnet + Ti-Biotite ± Ilmenite + H2O

Steeply dipping kinzigites with white, anatectic layers.

Extremely garnetiferous kinzigites.

Crossing Swamp.

Contact between Sacandaga Fm. and Rooster Hill Fm.
Crossing swamp that marks contact between the Sacandaga Fm. and megacrystic gneisses of the Rooster Hill Fm.

Megacrystic gneisses of Rooster Hill Fm.

Kinzigite in Rooster Hill Fm.

Type locality of Rooster Hill Fm.
North end of Stoner Lake. Type locality of Rooster Hill Fm. The Rooster Hill Formation is characteristic of a wide spread lithology throughout the Adirondacks. Its most characteristic feature is the presence of striking 1-4" megacrysts of K-feldspar, These are almost always flattened within the plane of foliation. Nonetheless, a number of these megacrysts preserve evidence of approximately euhedral crystal outline.
Compositionally the Rooster Hill megacrystic gneisses consist of orthopyroxene, garnet, hornblende, biotite, perthitic microcline, some plagioclase (oligoclase), and quartz. An igneous analogue would be quartz monzonite.
The parentage of the Rooster Hill megacrystic gneisses is obscure. It is not known whether the megacrysts are phenocrysts or porphyroblasts. The fact these lithologies are conformable with the enclosing stratigraphy over broad areas is consistent with a metastratified origin but does not rule out intrusion as sills. The lack of substantial banding across units thousands of feet thick is less consistent with a metasedimentary origin than with an igneous one. However, the problem remains unresolved and requires further research. Regardless of parentage, the Rooster Hill Fm. seems to correlate with the Blue Mt. Fm.

Contact of Rooster Hill Fm. and Peck Lake Fm.
Crossing contact of Rooster Hill Fm. and kinzigites of the Peck Lake Fm. Near the contact the Rooster Hill megacrystic gneisses become equigranular. This is probably due to cataclasis.

Kinzigites in the Peck Lake Fm.

A3: FAUNAL ASSEMBLAGES IN THE LOWER HAMILTON GROUP IN ONONDAGA COUNTY. NEW YORK
J.C. Brower, O.B. Nye, Jr., R. Belak, E.F. Carey, H.E. Leetaru, M. MacAdam, S.A. Millendorf, A. Salisbury, J.A. Thomson, P.O. Willette, S. Yamamoto
Department of Geology, Syracuse University, Syracuse, NY
This report summarizes a quantitative study of the paleoecology of the lower Hamilton Group in Onondaga County. This paper describes the faunal elements recognized and the ecological categories into which the taxa were grouped. The study confirms and extends the important works of Cooper (1930. 1933). Information concerning the multivariate statistical techniques, sedimentological data, and detailed analysis of the environments studied will be published elsewhere.
In Onondaga County the Hamilton Group directly overlies the Seneca limestone of the Onondaga Formation. Samples were taken from the Marcellus Formation, Skaneateles Formation, and the lower portion of Ludlowville Formation (Fig. 1). Although Rickard (1975, p. 6) notes that the Cherry Valley merges with the Seneca Member of the Onondaga limestone in the western part of the State, we have followed the traditional course in treating the Cherry Valley with the Hamilton Group.

A3: FAUNAL ASSEMBLAGES IN THE LOWER HAMILTON GROUP IN ONONDAGA COUNTY. NEW YORK

STOP 1: Top of the Onondaga Limestone
Top of the Onondaga Limestone and basal Union Springs Shale displaced by a small thrust fault.
The upper 8 ft of the Onondaga Limestone and about 10 ft of the Union Springs Shale are exposed on the side of the deep drainage ditch on the east side of the road. Exposures of the top contact of the Onondaga such as this are rare.
The Union Springs is the basal member of the Marcellus Formation. The three pelagic assemblages characterized by Styliolina fissurella, Pterochaenia fragilis, and Leiorhyncus limitare occur in the Union Springs.
At the south end of the drainage ditch a thrust fault with a throw of about 5 ft cuts the top of the Onondaga but is absorbed in the Union Springs Shale above by complex crumpling and jointing.

STOP 2. Chittenango and Cardiff shales.
The Chittenango and Cardiff Members of the Marcellus Formation are exposed at this stop. Both are sparsely fossiliferous, but representatives of the wood assemblage and the Leiorhynchus assemblage as well as scattered fish scales and pyritized cephalopod shells occur.
This shale is quarried by the Alpha Portland Cement Company for use in cement manufacture at its Jamesville plant. Although these shales are similar in appearance, they can be distinguished easily by their streaks. The Chittenango Shale, because of its relatively high content of carbonaceous matter, streaks brown when scraped by a hard object such as a geologic hammer, whereas the Cardiff streaks light gray. Examination of drill core from several test holes has shown that the change in color of the streak takes place within a vertical interval of 3 ft. The contact is placed where, in going downward, the streak becomes distinctly brown. Located in this manner, the contact is near the top of the lower face, 5 to 6 ft above the upper layer of large septarian concretions. Many of the septarian concretions in the upper part of the Chittenango are several ft across. The Cardiff shale on the other hand has only a few concretions and these are seldom more than 6 inches in diameter. The cracks within the septarian concretions commonly contain calcite, ferroan dolomite, and white, platy barite. Small crystals of barite with some pyrite also coat joint surfaces in the shale in places.

View of Allied Chemical Corp., Solvay Process Division Quarry on left.

STOP 3: Monocline in the Onondaga
Monocline in the Onondaga Limestone and exposures of the Union Springs Shale, Cherry Valley Limestone, and Chittenango Shale Members of the Marcellus Formation.
Walk south up the stream for about 500 ft to where the top beds of the Onondaga Limestone exposed in the stream bed dip northward due to the presence of a monocline that strikes about N70°W. This monocline probably grades into a thrust fault in the Solvay Process Division's quarry. Solution-widened tension joints are well-developed in the limestone on the monocline.
Continue up the stream to where it forks. About 15 ft of Union Springs Shale and about 3 ft of Cherry Valley Limestone are exposed at a small waterfall on the left branch not far from the fork. The Union Springs consists of black shale with numerous thin beds of black limestone. Styliolina fissurella, a small mollusk, shaped similar to a pencil point, is abundant in the shale of the upper part of the member. The Cherry Valley limestone forms the lip of the falls. It is characterized by a mixed pelagic and bottom dwelling fauna which includes cephalopods, the coral, Aulopora, brachiopods, trilobites, and crinoids. The basal few feet of Chittenango Shale, exposed in the stream bank above the falls, contains one or more thin beds of black limestone. Numerous Styliolina fissurella can be seen on the bedding surfaces of some of the shale.

STOP 4: Pompey Quarry
About 15 ft of the Pompey Member (Skaneateles Formation) is exposed here. The Pompey is a rather clean, coarse siltstone to fine sandstone which is crossbedded and may display current ripples. The Actinopteria and the Zaphrentid coral assemblage can be examined here. Each is concentrated usually along single bedding planes. Although the Zaphrentids usually are lying on their sides, they may be in growth positions.

STOP 5: Skaneateles Formation
Road cut in the Pompey, Delphi Station, and Mottville Members of the Skaneateles Formation. This cut exposes about 115 ft of the Pompey, Delphi Station, and Mottville Members. The 8 ft of siltstone at the top of the cut is Cooper's Eunella-Nyassa zone that marks the top of the Pompey, the same unit that forms the lip of Pratts Falls. The siltstone grades downward into gray shale.
The contact between the Delphi Station and the Pompey Members is not located easily and is one of the problems to be considered at this stop.
The Mottville is a fine-grained silty, somewhat calcareous, gray shale. Only the uppermost few feet can be seen here. The Tropidoleptus carinatus assemblage has been collected at this locality.
The overlying Delphi Station is a dark-gray, fine-grained shale with smaller amounts of calcium carbonate but more organic matter than the underlying Mottville. The relatively diverse Nuculoidea-Bembexia assemblage occurs here.
In the top-most Pompey Member, the muds of the Delphi-Station are replaced by current-rippled crossbedded siltstones. The Nuculoidea-Bembexia assemblage occurs in the lower portion to be replaced by the Actinopteria assemblage in the upper portion.

STOP 6: Delphi Station and Pompey Members
Delphi Station and Pompey Members of the Skaneateles Formation.
Observe the upper beds of the Pompey Member exposed near the top of the falls. Walk right on path along the edge of the gorge to where the falls can be observed.
The top 60ft of the falls is Cooper's (1930, Am. Jour. Sci. v. 19) type section of the Pompey member. The resistant siltstone beds that form the lip of the falls are his Eunella-Nyassa zone that marks the top of the Pompey, distinguished by the presence of Eunella lincklaeni, Athyris cora, and Nyassa arguta. The lower part of the falls exposes the upper part of the Delphi Station Member. The Mottville Member which underlies the Delphi Station is exposed a moderate distance downstream from the falls.

STOP 7: Small shale quarry
Small shale quarry in the Butternut Member of the Skaneateles Formation.
The Butternut is a bioturbated silty shale which contains the Leiorhynchus laura assemblage. This assemblage also occurs in the thin-bedded siltstones and silty shales of the Mottville and Delphi Station.

STOP 8: Otisco Member of the Ludlowville Formation.
Stop opposite the yellow brick house. Walk about 100 ft up the hillside on the west side of the road to exposures of siltstone strata that form a bench on the hillside. This is the siltstone platform on which the Staghorn Point coral biostrome was formed. It is about 50 ft above the base of the Otisco Member of the Ludlowville Formation and is an important horizon marker in the Syracuse area.
In the upper siltstone beds are numerous molds of corals representative of the Otisco coral assemblage.
In the lower siltstone platform, are several think discontinuous fossil-rich layer which contain members of the Mucrospirifer mucronatus assemblage.

STOP 9: Road cut in the Centerfield Member
Road cut in the Centerfield Member of the Ludlowville Formation. About 6 ft of the relatively clean, crossbedded fine sandstones of the Centerfield are exposed. Both the Mucrospirifer mucronatus assemblage which occurs concentrated along bedding planes and small patches of the Zaphrentid coral assemblage can be examined here. Glacial striae can be seen at the top of the outcrop.

A4: GEOMORPHOLOGY OF THE SOUTHEASTERN TUG HILL PLATEAU
Ernest H. Muller
Syracuse. NY
Few areas of comparable size in New York State are less accessible or less well known than the heart of the Tug Hill Plateau. The heaviest snowfalls in the eastern states make for brief growing seasons. Extensive tracts cleared and farmed in the past century have returned to second growth. The road net involves only jeep trails between a few broadly spaced transverse highways.
Although isolated by peripheral lowlands --the Black River Lowlands on the north and east, the Ontario lowlands on the west and the Oneida-Mohawk lowlands on the south --the Tug Hill is a crudely triangular outlier of the Southern New York Section of the Appalachian Plateaus Province. Rough accordance of summit elevations (e.g. 1960 ft at Gomer Hill. 1920 ft at Mohawk Hill) led Newell (1940) to relate physiographic history of the Tug Hill to that of the adjacent Appalachian Plateaus to the south, ascribing a major role to Tertiary peneplanation. Regional dip southwesterly away from the Adirondack Massif led Hanefeld (1960) to stress the cuestaform nature of the Tug Hill. The scarped east-facing border of the plateau contrasts with the gradual southerly and westerly dip slopes. Indeed both peneplanation and cuestaform development convey true, but incomplete impressions of the regional character of the Tug Hill subprovince. Each is incomplete in failing to emphasize the role of prolonged and repeated Pleistocene glaciation in isolating the plateau, in reducing summits and in shaping present topography. Perhaps because of the erodibility of underlying rocks, these effects are maximized in the southeastern portion of the plateau.
Rocks of Ordovician and Silurian age underlie the Tug Hill Plateau. At the base of the sedimentary section are carbonate rocks of the Trenton and Black River Groups which lie unconformably upon Precambrian metasediments of the Adirondack terrane. From Forestville north to Carthage, the contact between sedimentary and metamorphic rocks lies roughly along the course of the Black River and presumably exerted structural control upon development of the Black River Lowlands. Trenton, Utica, and Frankfort Formations of Ordovician age comprise the stepped and cuestaform eastern margin of the plateau. They also underlie the narrow, southeastern extension of the subprovince where regional dip approximates regional slope from the Black River to the Oneida-Mohawk Lowlands. As a result, Utica Shale underlies both northern and southern margins of this southeastern portion of the subprovince. The youngest Paleozoic strata of the plateau are the red and green sandstones and shales of the Medina Group which lie unconformably upon Queenston, Oswego and Lorraine rocks in the southwestern portion of the Tug Hill.
Knowledge of the geology of the Tug Hill has long been based chiefly on inference from studies in the peripheral lowlands. Surficial geology, for instance, was inferred from studies such as those of Taylor (1924), Stewart (1958) and MacClintock and Stewart (1963) in the St. Lawrence Lowlands; of Miller (1909a , 1909b), Fairchild (1912), Buddington (1934), Tyler (1938) and Force, Lipin, and Smith (1975) in the Black River Lowlands. Kaiser (1962) showed the responsiveness of glacial drift to immediate bedrock provenance and inferred prevailingly southeasterly glacial flow across the Tug Hill. Street (1966) on lithologic criteria delineated the interlobate area of rapid transition from characteristic eastern (Black River lobe) to western (Ontario Lobe) till in the area west of Ava. Jordan (1977, 1978) studied glacial deposits in the heart of the Tug Hill with a view to distinguishing relationships of wetland types to glacial geology. More specifically, published geologic information relating to the southeastern portion of the Tug Hill subprovince involves geologic mapping of the Remsen (Miller, 1909a), Oriskany (Dale, 1953) and Utica (Kay, 1953) quadrangles, surficial mapping by Wright (1972) and regional correlation by Fullerton (1971, in press).

A4: GEOMORPHOLOGY OF THE SOUTHEASTERN TUG HILL PLATEAU

Route follows the lowest of the Syracuse Channels
This route follows the lowest of the Syracuse Channels by which proglacial meltwater drained from Onondaga Trough east toward the Mohawk Valley. Exposures of Syracuse Formation in its type area are visible south of Erie Boulevard on right.

Floor of proglacial Lake Iroquois
Travel east across plainlands, the floor of proglacial Lake Iroquois. This area underlain by nonresistant Vernon Shale accounting for basin. Bedrock topography with local relief of 150 ft in next few miles is concealed by postglacial lake sediments.

Sandy, stone-free soil in fields on left.
Ephemeral strand line of low lake phase that succeeded Lake Iroquois in the Canastota mucklands is in trees at left. Dune modification of the back-shore sands is visible briefly and better developed along Chestnut Ridge Road which parallels the Thruway to the north.

Vernon Shale
Vernon Shale exposed in low roadside cut on right (south) side of eastbound lane, opposite Chittenango Service Area. For next several miles the strand of Lake Iroquois trends parallel to Thruway on the South.

Wampsville
One mile south of the Thruway, not readily visible is Wampsville, site of Madison County Courthouse. A well on the property of Hubbard Industries located near a Lake Iroquois spit, taps an artesian system at 90 ft and flows a reported 700 gallons per minute. Gravel pits south of Route NY 5 in Wampsville expose two impermeable lodgment tills with intervening permeable cobble gravel.

Iroquois barrier bar on right
Iroquois barrier bar on right about 0.2 m; before railroad underpass. Leave bed of Lake Iroquois.

Herkimer Sandstone of uppermost Clinton Group
Herkimer Sandstone of uppermost Clinton Group exposed south of eastbound lane discontinuously for 0.25 mi.

Descend and cross Oriskany Creek.
Roadcuts expose stratified drift indurated at base, overlying firm, dark-gray, silty clay till.

Whitestown Esker
Small gravel pit beneath power line was opened in the Whitestown Esker which parallels route on the right.

STOP 1. Stream cut bluff of Oriskany Creek
Stream cut bluff of Oriskany Creek, exposing intercalated lodgment tills and deformed lake sediments overlain by firmly cemented fluvioglacial gravel. The section records multiple oscillations of the Late Wisconsinan ice margin into pro-glacially impounded waters.

Stratified drift
A few exposures of stratified drift across Oriskany Creek on the right. Out of sight to the south, the Whitestown Esker leads to the kame moraine south of Oriskany which fronts on the Oriskany-Whitestown Sand Plain at approximately 550 ft above sea level. Numerous exposures in bluffs facing the Mohawk River show the Sand Plain to be underlain by 80+ ft of horizontally bedded sand and gravel, capped by 10 to 20 ft of coarse cobble gravel, in part firmly cemented with calcium carbonate.

Shale exposed in roadside ditches and gully at right.

Rise onto pitted outwash plain.
Irregular closed depressions due to melting of buried stagnant ice masses on both sides of road. Surface of undissected plain is about 525 ft above sea level, graded below the Oriskany-Whitestown Sand Plain. This surface is a sandur built where meltwater streams flowing along the margin of a progressively receding ice front spread onto the open valley floor.

Cobble gravel in a few low knolls
The extensive sand mantle gives way to cobble gravel in a few low knolls. East of the road, weak channel development trends ESE.

Marginal meltwater channel
A well-developed, flat-floored marginal meltwater channel 250-300 ft wide, and cut into Utica Shale opens onto the sandur west of Floyd. North of Floyd, rise on drift mantled slope which in places shows low constructional topography.

STOP 2. Gifford Hill Roadcuts
Exposure of multiple tills, intercalated with partially indurated intraglacial stratified drift units.

Eastward dipping foreset
Note indurated, eastward dipping foreset cobble to boulder gravel in roadcut on right.

Narrow, steep-walled defile
Eastward from Frenchville, Route NY 274 occupies the floor of a narrow, steep-walled defile incised by Wells Creek. Cut 200-ft deep in postglacial time, the gorge owes its character to rapid incision and the erosivity and vertical jointing of the Utica Shale. The gorge is incised into a fluvioglacial terrace at 800 ft above sea level built eastward into the Steuben Basin.

Outflow used to be to the east
Prior to incision of the Wells Creek Gorge, this part of the basin of Big Brook was impounded. As long as the ice margin blocked westward drainage, outflow was east past Merrick Corners and down Steuben Creek. Freeing of the Mohawk Valley north of Rome initiated westward drainage, leading to incision of the gorge.

Climbing from flood plain to proglacial lake
climbing from flood plain of Big Brook to floor of proglacial Steuben Lake. Nearshore sands exposed in borrow pit on right. Just beyond borrow area, roadside ditch exposes oxidized calcareous lodgment till with silt-loam matrix.

OPTIONAL STOP
Gully at right exposes black Utica Shale over Trenton Limestone. Roadside exposures contain dark gray till glutted with Utica Shale material near base, but with bright clast lithologies dominated by blue-gray carbonates with subordinate red sandstone and metamorphic rock types.

Vista southeast over Steuben Valley.
Note increasing abundance of metamorphic boulders beyond this point.

LUNCH STOP. Baron Steuben State Memorial Park.

Pass Capel Ucha, Cemetery
Pass Capel Ucha, Cemetery on site of old Welsh Church established 1804.

Cross meltwater channel

STOP 3. Barneveld Kame Complex
Extensive gravel and sand pits expose coarse cobble gravel overlying thick stratified coarse sand section.

"Drumlin lodge" on right; not a drumlin sensu stricto.

Minor moraine ridge cuts across road
Minor moraine ridge cuts across road, then seen on left, south side of road.

Kettles in stagnant ice zone

Course of proglacial meltwaters
Turn left, north, on Route NY12, roughly parallel to Cincinnati Creek and the course of proglacial meltwaters which drained from proglacial Lake Forestport in the south end of the Black River Valley. This region is broadly underlain by Trenton Limestone.

Floor of Lake Forestport
Swampy lowlands now drained by Cincinnati Creek comprised part of the floor of Lake Forestport.

End moraine remnants
End moraine remnants looping across valley presumed to mark minor still-stand of Black River glacial lobe.

Alder Creek Moraine
At Alder Creek, cross dissected Alder Creek Moraine built while the Black River glacial lobe impounded the southward-draining proglacial Lake Forestport in area of present Kayuta Reservoir. Westward, Alder Creek moraine includes extensive stagnant ice deposits and the Echo Lake Esker.

Dissected remnants of kame moraine
Park Hill and Sperry Hill to right (east) of Route NY 12 in southern outskirts of Boonville are massive sand and gravel mounds, interpreted as dissected remnants of kame moraine.

STOP 4. Allied Chemical Company, Boonville Limestone Quarry.
Formerly Delia's Quarry, as access to Sugar River. We do not have permission to examine the quarry as such. Warning: beware of mosquitoes, algal slime on rocks in stream bed, poison ivy, and cow patties! Objective is to examine classic solution pits in limestone and subterranean piracy in progress.

Locks of the old Black River Canal
Note masonry of several locks of the old Black River Canal in roadside exposures. first on the left (east), then on the right (west) side of the road. Built in 1855 to link navigable reaches of the Black River north of Lyons Falls with the Erie Canal at Rome, the Black River Canal was only briefly economical. With a total of 109 locks in 35 mi. the canal crossed a divide 700 ft above the Erie Canal.

Morainal topography
Morainal topography on right (west). Large sand and gravel knoll on left (east). Similar to Sperry and Park Hills. Descend 30 ft to valley floor.

Channel across Trenton Limestone ledge rock
Crossing the broad, flat-bottomed rock-floored channel across Trenton Limestone ledge rock at the head of Boonville Gorge. This ledge controlled outflow from proglacial Port Leyden Lake. Cross feeder canal for Black River Canal. Continue south parallel to an incised and constricted channel-way, thence crossing diagonally back to west side of valley to parallel the old Black River Canal.

Shale bluff in roadcut on right
Shale bluff in roadcut on right indicates erosivity of rock into which the Boonville Gorge is cut. To this point the valley has become progressively narrower. The distance that minor ridges of the Alder Creek Moraine project southward down Boonville Gorge indicates prior meltwater drainage toward Rome.
At left, across Boonville Gorge, lansing Kill enters from the east side of the valley. Originating as a meltwater stream marginal to the Alder Creek Moraine on the flank of Potato Hill. Lansing Kill has, from this point down valley inherited the valley of a short-lived but powerful stream, the outlet of proglacial Port Leyden Lake. Postglacial incision by Lansing Kill accounts for abrupt deepening of the narrow inner gorge at this point. Its proglacial predecessor deepened the valley some 175 ft.

OPTIONAL STOP: Pixley Falls, Boonville Gorge State Park

"Five Combines"
"Five Combines" - a Flight of 5 adjacent locks where the old Black River Canal crosses a limestone ledge on the side of Boonville Gorge.

Mohawk River enters Boonville Gorge from west
Mohawk River enters Boonville Gorge from west with multiple terraces now incised by both Lansing Kill and Mohawk. The highest terrace, above 1000 ft is an ice marginal delta plain. Lower terraces have correlatable equivalent remnants on the east wall, indicating they were fluvial and graded to lowering base level controls in the Mohawk Valley to the south.

Grave of William Floyd
Grave of William Floyd, signatory of Declaration of Independence is on right. Floyd Homestead was on left.

Vista across Delta Reservoir
Vista across Delta Reservoir, artificially impounded in the basin created by deposition associated with Stanwix glaciation across the mouth of Boonville Gorge. In postglacial erosion the Mohawk River failed completely to recover the bedrock valley. At the site of the Delta Reservoir Dam, it incised a steep-walled, 80-ft deep defile into Utica Shale.

The route now crosses a gravel plain (sandur)
The route now crosses a gravel plain (sandur) similar in origin to the plain of Nine-mile Creek crossed this morning. Marginal meltwater channels pinned against the plateau margin to the north here spread onto the basin floor.

Former Village of Delta
Half a mile west of this point was the Village of Delta. Inundated by construction of the dam in 1911, it survives only in the name of the reservoir that supplanted it.

Traveling over Rome Sand Plains

Continue southwest across Rome Sand Plains.
Following demise of Lake Iroquois the sandy sediments delivered by Fish Creek and other streams draining the Tug Hill were vulnerable to wind erosion as indicated by low dune and blowout topography.

Abandoned Erie Canal
Route NY46 follows the abandoned Erie Canal which has been restored as parkway, canoe, and bicycle path.

A5: BENTHIC COMMUNITIES OF THE LUDLOWVILLE AND MOSCOW FORMATIONS IN THE TULLY VALLEY, ONONDAGA COUNTY
Thomas X. Grasso
Prof. Geoscience Dept.
Monroe Community College
Rochester, New York 14623
The Devonian System in New York State varies from carbonates below (Ulsterian and lowest Erian Series) to coarse continental clastics at the top (Chautauquan Series), and represents a westward migrating deltaic complex built during Middle and Late Devonian time.
This deltaic complex, the Catskill Delta, is today represented by a wedge of sedimentary rock that thickens and coarsens eastward. The clastic wedge is pierced at several horizons by relatively thin, but geographically widespread, lithologically distinct units that do not change facies as rapidly as the rocks above or below. Serving as time planes, these key beds subdivide the clastic wedge into a number of major time-stratigraphic units. Three carbonate keybeds in the lower portion of the wedge serve to subdivide the lowest time stratigraphic unit, the Hamilton Group (Middle Devonian), into four formations, which are from oldest to youngest: the Marcellus, Skaneateles, Ludlowville and Moscow Formations.
The Middle Devonian Hamilton Group of New York State is structurally simple and highly fossiliferous, thereby lending itself to detailed stratigraphic, paleontologic, and paleoecologic studies. In Central New York it consists of approximately 1,000 feet of shales, silty shales and siltstones lying above the Onondaga Limestone and below the Tully Limestone. The stratigraphic relations of the Hamilton Group of New York as now understood were first clarified by Cooper's classic papers (1930, 1933).
The Hamilton rocks in the Tully Valley dip to the south 25° west at approximately 48 feet per mile, based upon the Centerfield Member as a datum (Grasso. 1966). The value obtained for the dip agrees with Cooper's (1930) estimate of 45 to 50 feet per mile to the southwest.
Superimposed on the regional dip are local low anticlines and faults. A thrust fault with associated folding occurs just south of Marcellus along NY Route 173 (Smith, 1935). Oliver (1951) shows conclusively that several normal faults, downthrown to the north, occur on the southwest side of the Tully Valley near Lords Hill. A thrust fault in the Onondaga Limestone and overlying Union Springs Member can be seen 1 mile south of Nedrow (Prucha, 1964, p. 49).
HAMILTON SECTION IN THE TULLY VALLEY
In the Tully Valley, the Hamilton is composed mainly of two facies that transgress time westward. The lower is a fissile black and dark shale facies of the anaerobic distal basin containing a low diversity primarily pelagic fauna. Lying above this facies in the Tully Valley, but partly contemporaneous with it farther to the east, is one representing a subtidal shelf-delta platform environment of silty shales and siltstones carrying a high diversity benthic fauna. The Ludlowville and Moscow Formation typify this facies in the Tully Valley.

A5: BENTHIC COMMUNITIES OF THE LUDLOWVILLE AND MOSCOW FORMATIONS IN THE TULLY VALLEY, ONONDAGA COUNTY

STOP 1. Joshua Sub-member (15')
STOP 1. Base of tower on Miller Hill, Joshua Sub-member (15')

STOP 2. Roadcut on west side of LaFayette Rd.
About 30' of the Upper Otisco Member and the Mucrospirifer-Spinocyrtia-Megastrophia Community is exposed here.

US 20 built on surface of large hanging delta

STOP 3. Roadcut on NY 80
Joshua Sub-member (Elev. top 1280')

STOP 4. Roadcut on NY 80
Owasco (2') Portland Point (10') Members (Elev. 1380')

STOP 5. Peppermill Gulf
Peppermill Gulf just east and parallel to Hogsback Rd. Centerfield Member (20-30')

Descend Eastside Tyler Hollow
Descend Eastside Tyler Hollow Nine Mile Creek (Otisco Lake outlet)

Old Borodino Quarry
Bioherm in Tully Ls. on left and roadcut on NY 41

STOP 6. Staghorn Point.
This is the type section of the Staghorn Point Sub-member (4'). The siltstone platform and overlying Otisco shales are well exposed here.

Bucktail Falls Ravine
Bucktail Falls Ravine on right exposing the entire Upper Hamilton Group from the Centerfield Member to the Tully Ls.

STOP 7. Fellows Falls Ravine
Fellows Falls Ravine down from Woodmancy Rd. A complete section in the Ludlowville Form. is exposed at this locality as follows:
Owasco | 2' | Elev. 1120' Falls at top of ravine
Spafford | 25'
Ivy Point | 40'
Otisco | 165' | Staghorn Point 7'
Centerfield | 20' | Elev. 880'

NY 80 follows Moraine crest of Tully

Descend north side of Tully Moraine

STOP 8. Unnamed ravine on east side of Tully Valley
Unnamed ravine on east side of Tully Valley up from NY 11A. The section exposed here is similar to Fellows Falls Ravine (STOP 7) with the exception of the lower Otisco covered from the Upper Centerfield to the Staghorn Point siltstone platform. The Owasco is also not exposed here. (NOTE : This stop may be omitted depending on time schedule).

STOP 9. Tinkers Falls Ravine
Tinkers Falls Ravine up from east side of NY 91. About 80' of Windom is exposed here with the Tully ls. forming the cap rock of Tinkers Falls (Elev. 1380' )". The
Mucrospirifer-Chonetes Community is well exposed in the first exposure upstream at base of

STOP 10. Roadcut on east side of US 11.
About 30' of Windom is exposed here carrying the Mucrospirifer-Chonetes Community.

A6: PALEOENVIRONMENTS OF THE POTSDAM SANDSTONE AND THERESA FORMATION OF THE SOUTHWESTERN ST. LAWRENCE LOWLANDS
Bruce W. Selleck
Colgate University, Hamilton, New York
In northwestern New York State the Upper Cambrian-Lower Ordovician Potsdam Sandstone and Theresa Formation exhibit a variety of primary structures and compositional and textural variations indicative of deposition in nearshore, usually tide-dominated, settings. The purpose of this paper is to provide a descriptive overview of these units, plus an interpretation of the depositional environments of the various lithofacies.
In the study area) the Potsdam and Theresa are best exposed in the Frontenac Axis region. In this area the Paleozoic rocks lie in profound unconformity upon a paleoerosional surface underlain by metamorphic rocks of Proterozoic age.

A6: PALEOENVIRONMENTS OF THE POTSDAM SANDSTONE AND THERESA FORMATION OF THE SOUTHWESTERN ST. LAWRENCE LOWLANDS

STOP 1. Outcrop on both sides of road.
This outcrop displays the angular unconformity between the Potsdam Sandstone and Proterozoic rocks metamorphosed during the Grenville Orogeny (approximately 1.1 billion years ago). As the Potsdam here is approximately 500 million years old, the unconformity represents some 600 million years of missing geologic history. The Potsdam here is typical Potsdam I lithofacies. Note the general absence of trace fossils in the Potsdam, the scarcity of metamorphic clasts in the basal Potsdam and the weathering and loading deformation of the Proterozoic rock along the unconformity.

Excellent exposures of Potsdam I on right.

STOP 2. Outcrop on both sides of road.
This outcrop again exposes the angular unconformity between the Potsdam Sandstone and Proteroizoic metamorphic rocks. Of major interest at this stop are the striking color patterns in the Potsdam. Glacial polish on the top of the outcrop reveals numerous generations of color streaks. The coloring agent of the sandstone is mainly Fe2O3 (hematite) but titanium oxides and other trace minerals are locally important. The coloring oxides occupy a variety of petrographic positions in thin section, occurring as grain coatings, oxidation "halos" around detrital opaque minerals and as disseminated blebs and flecks in secondary silica cement.

Excellent exposures of Proterozoic metamorphic rocks.
Beginning of excellent exposures of Proterozoic metamorphic rocks. These continue for 1.5 miles.

STOP 3. Outcrop of right side (SW) of road.
The contact between Potsdam I and Potsdam II lithofacies is exposed at this stop. The lower portion of the outcrop is typical Potsdam 1. The upper, massive portion is Potsdam II and is obviously riddled with trails and burrows. One burrow of interest is Diplocraterion Yoyo (see text). Odd funnel-shaped structures ("sand volcanoes"?) and glacial straiae may be observed on the top surface of the outcrop. Brecciated lenses and pods occur in Potsdam I at this stop (lower portion of outcrop on NW side of road). These breccias are interpreted to be the result of the cementation and subsequent breakup of soil-like silcrete crusts formed during periods of subaerial exposure.

STOP 4. Outcrop on both sides of road.
The contact between the Potsdam Sandstone (Potsdam II lithofacies) and the Theresa Formation (Theresa I lithofacies) is displayed prominently at this stop. The contact is marked by a color change (Potsdam -gray-white-yellow; Theresa gray-brown), a greater carbonate content in the Theresa and differences in bedding style and texture. Features to observe here include body fossils (a few discoidal gastropods and fragments of Lingulepis accuminata, an inarticulate brachiopod, trace fossils (especially diplocraterion yoyo in the upper portion of Potsdam II and a variety of primary structures (ripple marks, low angle crossbeds). Bimodal laminae in some of the low-angle planar crossbeds in Potsdam II at this stop suggest a nearshore (possibly beach) depositional environment. Note also the outcrop of Proterozoic gneiss 0.25 miles SW on Rt. 12 illustrating the probable irregularity of the pre-Potsdam erosional surface in this region.

STOP 5. Outcrop on right (SE) side of road.
The Potsdam II - Theresa I contact again is exposed at this stop. Rather.good specimens of the inarticulate brachiopod Lingulepis be obtained from the thickly bedded portions of the uppermost Potsdam near the contact. As we walk to the NE end of the outcrop, note the loss of the thin-bedded nature of Theresa I and the increase in bioturbation. This signals the base of Theresa II (Theresa IIB) lithofacies. Numerous quartzite cobbles may be seen in the otherwise fine sand of Theresa I at this stop. Mechanisms for the transport of such large particles remain open to conjecture.

The rhythmic interbedding here is typical of Theresa II lithofacies in the region. In the light-colored quartz sandstone strata (Theresa IIA) a variety of crossbed styles may be observed. Note the occasional occurrence of herringbone crossbeds. The darker (Theresa IIB) calcitic and dolomitic sandstones are intensely bioturbated resulting in the loss of all primary current-formed structures. The folding here is typical of parts of the region, and is presently under study (see article by Bursnall and Barber, this volume). A small fault also is present in this exposure.

STOP 7. The uppermost lithofacies of the Theresa
The uppermost lithofacies of the Theresa Formation, Theresa III, is exposed here. All four lithologies described in the article are observable at this stop. Numerous features indicative of subaerial exposure, including mudcracks and interclast breccias, are well exposed.

A7: BENTHIC MARINE COMMUNITIES IN THE UPPER ORDOVICIAN CLASTICS OF THE TUG HILL REGION, NEW YORK
Peter Bretsky
SUNY, Stony Brook
and
David Thomas
SUNY College at Oswego
The fossiliferous shales, siltstones and sandstones of the Upper Ordovician Lorraine Group are an excellent example of well-defined offshore-to-onshore benthic marine communities. Three communities have been recognized and described by Bretsky (1970), based upon the consistent and recurrent associations of the abundant invertebrate species. They are;
(1) Onniella-Sowerbyella Community: widespread; lived on muddy silts of the outer infralittoral zone; abundant brachiopods (dalmanellids, strophomenoids, atrypids), crinoids, bryozoans (trepostomes) and trilobites with gastropods (pfeurotomariids) abundant locally.
(2) Nuculites-Colpomya Community: wide spread; lived on or buried in silts and fine sands of the outer and inner infralittoral zone protected environments; abundant bivalves (nuculoids, modiomorphids, actinodonts), crinoids, and brachiopods (orthids).
(3) Ambonychia-Modiolopsis Community: patchy distribution; lived on or partially buried in medium to coarse sands in the shallow infra littoral and exposed intertidal environments; abundant bivalves (ambonychiids, modiomorphids, cyrtodonts), monoplacophorans with locally abundant gastropods (pleurotomariids, bellerophontids), crinoids, bryozoans (trepostomes) and cephalopods (orthocones).
The pattern of brachiopod-dominated offshore communities to mollusc dominated nearshore communities seen in the peri-Tug Hill region is characteristic of many Late Ordovician deposits (see Bretsky, 1969).
SUMMARY
The exposures in the Tug Hill area give a picture of the dynamics of organic change in an offshore-to-onshore depositional regime. Into this general sedimentological framework, three benthic marine communities are placed. They occupied a gently westward sloping shelf that was receiving sediment from the east and that, through time, was experiencing a long, gradual regression. What happened to the faunas in this regression? To explain the exact nature of the faunal transitions in a temporal sense, a detailed bed-by-bed analysis is necessary. For example, the Lorraine Gulf section treated in this manner provides the opportunity to analyze species over a temporal gradient. In these long ranging faunas, species replacements, species additions , species losses and mixing phenomena can be examined throughly. Set in this environmental complex, are the Changes in these populations gradual? The exposures in this area are "untapped" with respect to these questions.

A7: BENTHIC MARINE COMMUNITIES IN THE UPPER ORDOVICIAN CLASTICS OF THE TUG HILL REGION, NEW YORK

STOP 1. Salmon River, stream cut exposures
Salmon River, stream cut exposures near railroad trestle. The organisms here are large, suspension feeding mollusks in the coquinite beds. Note the lack of abrasion and sorting of the shells. The deposition was in the low energy mode on a shallow, gently sloping shelf. Depositional events were episodic but not violent. The mud fauna is made up of infaunal suspension and detritus feeders. Sedimentary structures to be observed here include large dune sets. several sets of ripples and desiccation (?) features. "Turkey tracks" and "U"-shaped tubes should also be noted. This outcrop illustrates a proximal facies.

STOP 2. Salmon River Falls.
CAUTION !!! This stop involves considerable climbing; footing is poor; do not go near the brink of the falls. This outcrop exhibits the transitional nature of the Oswego-Pulaski boundary. It is the most proximal facies and here we see the last of Upper Ordovician marine sediments. Compare the features of a higher energy regime with those features of STOP 1. Inspect the nature of the fossils and biogenic structures in the Pulaski with the unfossiliferous Oswego Sandstone.

STOP 3. Lorraine Gulf.
Exposures are 0.3 miles north of intersection. Bus will not be able to travel this road. Participants will walk to exposures from here and return to bus at this point. At this outcrop a more distal facies is exhibited. The sediments were deposited early in the regressive phase. Note the taxonomic and preservational changes exhibited here. What is the same when compared to the previous outcrops?

STOP 4. Washington Park. Stream cut exposures.
This the most distal sedimentary facies. Stratigraphically, the exposures are lowermost Pulaski, just above the shales of the Whetstone Gulf Formation. Notice the fairly unfossiliferous nature of these beds (what fossils are found?) and the predominance of the shales to siltstones (compare with earlier outcrops).

A8: PUNCTUATED AGGRADATIONAL CYCLES (PACS) IN MIDDLE ORDOVICIAN AND LOWER DEVONIAN SEQUENCES
E.J. Anderson and Peter W. GoodWin
Temple University
Barry Cameron
Boston University
Hypothesis
Observations of numerous clastic and carbonate sequences as well as recent papers on asymmetric cycles (Ryer, 1977; Beukes, 1977; Talbot, 1974) have led us to the hypothesis that all geosynclinal and cratonic sedimentation occurs as upward-shallowing (aggradational) cycles following rapid non-depositional transgressions (Fig.1). The general hypothesis can be viewed as a series of increasingly interpretive statements:
1) Sedimentary sequences consist of upward-shallowing packages separated by sharply defined surfaces (punctuated aggradational cycles).
2) These sharp surfaces represent intervals of rapid transgression during which no net deposition occurs. All deposition is aggradational during relatively long stable periods following transgressive events.
3) Therefore large-scale transgression is not a continuous process but rather an episodic one. Large-scale transgressive sequences consist of numerous punctuated aggradational cycles (Fig.1): basin-wide transgression is accomplished through a series of deepenings and shoalings, not by a continual deepening.
4) Rapid transgressive episodes are caused by basin subsidence.
5) Rapid basin subsidence occurs in response to abrupt movements of the elastic lithosphere.
The primary purpose of these two field trips is to demonstrate that two chronologically distinct sedimentary sequences, representing a broad range of environments, consist entirely of punctuated aggradational cycles (PACS). These two generally transgressive carbonate sequences (Black River and Helderberg), traditionally described as successions of numerous formations and members, can be viewed in a more genetic and integrative sense as sequences of a single depositional motif: punctuated aggradational cycles. The spectrum of environments is sufficiently broad to suggest that this motif is pervasive and applicable to all paleoenvironmental situations.
A second purpose of the trips is to introduce some of the stratigraphic implications of the PAC Hypothesis. Application of the PAC idea raises questions such as:
1) What is the relationship between aggradational cycles and traditional stratigraphic units (formations and members)?
2) What are the paleogeographic implications of episodic transgression? Was paleogeography modified with each transgression? Is it still valid to view large-scale transgression as a gradual shoreward migration of a relatively fixed geographic pattern. i.e. does Walther's Law apply?
3) Can cycles and transgressive surfaces be traced throughout the basin? Are subsidence events basin-wide and essentially synchronous? If so, are transgressive surfaces the ultimate means of intrabasinal correlations?

A8: PUNCTUATED AGGRADATIONAL CYCLES (PACS) IN MIDDLE ORDOVICIAN AND LOWER DEVONIAN SEQUENCES

STOP 1: Northwest Newport Quarry (locality NPQ)
Walk about 300-400 feet along the gravel road and then descend carefully the southeast section of the quarry where the lower and middle Lowville Limestone is well-exposed. Then walk west around the treed promontory to the southwestern part of the quarry where the middle upper Lowville can be examined along with fallen blocks of the Watertown Limestone. Stay away from the southern wall which is about to collapse! Ascend the grassy slope here or walk back around to the center of the treed promontory and walk up the overgrown old "roadway" to examine the Watertown Limestone at the top of the quarry. The contact with the overlying lower Trenton Kings Falls Limestone is exposed in a quarry southwest of Newport (Kay, 1953), but not here.
Three formations are exposed in the large northwest Newport Quarry: the Late Cambrian Little Falls Dolostone and the Medial Ordovician (Black River Group) Lowville and Watertown Limestones (Cameron & Kamal, 1977). The top of the sandy upper Little Falls presumably forms the quarry floor. The Lowville can be divided into a lower sandy dolomitic member (13.5') and an upper purer limestone member (21.5'). A metabentonite and a 2-foot thick argillaceous marker horizon, both useful for local correlation (Cameron & Kamal, 1977), are at about 9 and 30 feet, respectively. The Watertown Limestone at the top of the quarry is massively bedded, burrow-reworked, black chert-bearing and fossiliferous calcisiltite and calcarenite. The fauna is more diverse and fossils are more common than in the Lowville below, but they are hard to collect. Large tabulate corals, brachiopods, mollusks, and bryozoa are evident.
Ten cycles that average 4 feet in thickness have been identified: three in the lower Lowville Limestone (Cycles 1-3), six in the upper Lowville (Cycles 4-9), and at least one in the Watertown (Cycle 10). Another cycle in the Watertown is postulated by correlation with nearby exposures. The three lower dolomite Lowville cycles are interpreted as representing restricted tidal conditions. At their bases they are argillaceous and contain horizontal burrows. Horizontal algal stromatolitic laminations, fenestral fabrics, and vertical burrows occur mostly in the middle. The quartzose tops of cycles 2 and 3 may be lag deposits from tidal channels. They both contain quartz arenites at the base of the sandy beds and the upper one is quite fossiliferous. The upper Lowville contains six less restricted tidal cycles. Their bases are typically abrupt, burrow-reworked, and fossiliferous. The lower and middle parts are typically argillaceous. Towards their tops they become more micritic. Vertical burrows, intraclasts, fenestral fabrics, and stromatolitic laminations are common.
The Watertown Limestone is subtidal, possibly shallow shelf or lagoonal in nature, and less restricted than the Lowville, as evidenced by the thorough burrow-reworking and by the diverse invertebrate and calcareous algal fossil assemblages here and elsewhere. Most of the shelly fossils are concentrated at the bases of small subcycles 6 to 12 inches thick that mimic larger cycles.

Lowville Limestone
After coming down hill, continue straight onto dead end dirt road. Poor exposures of lower Trenton Group (Napanee Limestone) on left. (Do not turn right onto the large bridge over East Canada Creek. However, if the power company (Niagara-Mohawk) does not permit your trespassing, park and walk across the large bridge. Descend the left (upstream) side to the large limestone exposures at the inside of the meander to see all but the base and top of the Lowville Limestone. The 4 foot thick, Watertown-like, burrow-reworked, massively bedded subtidal facies caps the exposure).

STOP 2. Inghams Mills
Walk to right, through the grass, and proceed to the right of the wire fence, walking beneath the power lines.
At the stone wall along the edge of the field, bear left and walk along the wire fence. CAUTION: Poison ivy often grows in abundance along this path.
Opposite the brick building, turn right and proceed very carefully over to the boulders and across the creek toward the base of the outcrop. The boulders you will have to walk over to get to this exposure are sometimes unstable and tend to move when stepped or climbed upon. Be careful! Traverse at your own risk.
Three limestone formations of Medial Ordovician age are excellently exposed along with the top of the Late Cambrian Little Falls Dolostone below the dam on East Canada Creek. The Lowville here comprises the whole of the Black River Group although a Watertown-like 4-foot thick horizon occurs near the top. The Trenton Group above is represented by an unusual facies of the Napanee Limestone and the Kings Falls Limestone, including what was once attributed to the Sugar River Limestone (Kay, 1968; Cameron, 1969). At this well-exposed outcrop, the field trip participants will be encouraged to use the many paleoenvironmental criteria observable here in an attempt to recognize the punctuated aggradational cycles themselves. After an outcrop discussion, we will leave to look at Devonian cycles.
Little Falls Dolostone. Two feet of the Late Cambrian Little Falls Dolostone are exposed at this locality. The top of this unit has two feet of relief and is relatively thick-bedded, light to medium brown weathering, quartz arenitic, pyrite-bearing dolostone with thin inter-bedded shale layers.
Lowville Limestone. Approximately 30 feet of Lowville are exposed, beginning with several feet of fossiliferous gray shaly limestone at the base. Middle Lowville contains horizontally laminated (algal?) calcilutites with abundant vertical burrows, a few ostracodes, and mudcracks confirming an intertidal origin. Tide channels (Cameron, 1969; Cameron and Kamal, 1977) are well-exposed on the southern and western sides of the lower outcrop. The upper half of the formation contains subtidal fossiliferous burrow-reworked calcisiltites overlain by intertidal vertically-burrowed lithologies. The subtidal lithologies resemble the Watertown Limestone to the Northwest.
"Napanee Limestone". -The lowest 13 feet of Trenton(?) limestone consists of a lower 7.5 foot unit of chocolate brown argillaceous calcisiltites and calcareous shales overlain by a 5.5 foot unit of gray less argillaceous calcisiltites interbedded with thinner shales.
Kings Falls Limestone. Twenty-three feet of brachiopod-rich shelly, lower Kings Falls Limestone overlies the "Napanee". The upper Kings Falls (14 feet) consists of encrinitic bryozoan-rich calcarenites.
Using these general lithologies and thicknesses for stratigraphic location, field trip participants will attempt to recognize punctuated aggradational cycles from criteria demonstrated at Newport Quarry. A blank columnar section (Fig.6) is provided for recording PACS with lithologic documentation. Formational boundaries are indicated along with vertical measurements for purposes of location. After outcrop analysis by small groups of participants there will be a full-group discussion of the outcrop.

STOP 3. Jordanville Quarry
Eight cycles are exposed in the quarry, two in the upper Dayville and Elmwood, four in the Jamesville and two in the Deansboro (Fig.B). The Clark Reservation is probably not present (it appears to terminate further west). The two lower cycles (I and II) are thick and grade from coarse more argillaceous and fossiliferous beds up into fine very well sorted dune cross-stratified calcarenite. Note that these beds, which include the Elmwood Member of the Manlius, are not dolomitic algal laminites as they are further west at Munnsville and Perryville. The next three cycles in the Jamesville (III to V) are stromatoporoid-algal laminite cycles; laminites are well-developed only in Cycle III. These laminites, which are well developed in Cycle III in the north wall of the quarry, are not present less than a quarter of a mile away in the south wall. Cycle VI (Fig.B), a three foot cross-stratified calcarenite, has erosional upper and lower surfaces. This can be interpreted as a barrier island deposit bounded on the bottom by a migrating tidal inlet erosion surface and on the top by a ravinement. Cycles VII and VIII (the Deansboro) are shallow open shelf cycles consisting of bioturbated crinoid-brachiopod calcarenite which grades upward into current stratified deposits.

A9: EURYPTERID HORIZONS AND STRATIGRAPHY OF THE UPPER SILURIAN AND LOWER DEVONIAN ROCKS OF CENTRAL-EASTERN NEW YORK
Samuel J. Ciurca, Jr.
Rochester, New York
There are a number of famous faunas known from classic localities in North America. These include the "Mazon Creek" Fauna (Pennsylvanian) of Illinois, the Kokomo Eurypterid Fauna of Indiana, the Green River Fish Fauna (Eocene) of Wyoming, and the Burgess Shale Fauna (Cambrian) of western Canada. Each is characterized by an unusual abundance and variety of species.
In New York the so-called "Bertie" eurypterids are representative of one such fauna (Fig. 1). Although only one or two species of eurypterids dominate the fauna, a large number of species has been described through the years. Unfortunately, detailed stratigraphic studies of the eurypterid-bearing beds have been noticeably lacking. Until recently, the "Bertie" faunas, one from the Buffalo area (so-called "Buffalo Pool"), and the other from eastern New York (so-called "Herkimer Pool "), were thought to be contemporaneous deposits rather than distinct stratigraphic horizons.
The purpose of this paper and the associated field trip is to relate these and other eurypterid horizons to the stratigraphy of the areas. Several formations are discussed but special emphasis is given to the Chrysler Formation because it is the least known and only recently was well exposed for study.
2014: No road log, and locations are not given with sufficient information to locate them reliably. Hence, no stops or views.

A9: EURYPTERID HORIZONS AND STRATIGRAPHY OF THE UPPER SILURIAN AND LOWER DEVONIAN ROCKS OF CENTRAL-EASTERN NEW YORK

A10: AN EXAMINATION OF BOTTOM SEDIMENTS IN SENECA LAKE
Donald L. Woodrow
Professor of Geology
Hobart and William Smith Colleges
Geneva, New York 14456
The purpose of this field trip is to examine data bearing on the origin of the sediments found in the northern part of Seneca Lake. These sediments are apparently typical of those found in the other Finger Lakes of New York so that learning about the processes which formed them gives insight into the general problem of the origin of sediments in these lakes and similar lakes elsewhere.
The valley in which the lake is situated has been cut into the South-dipping Devonian shales and sandstones of the Appalachian Plateau (Figure 1). Apparently, a north-flowing stream occupied the valley during the late Tertiary and then during the Pleistocene glaciers eroded and otherwise sculpted the Tertiary landscape mantling the resulting surface with a wide variety of ice-laid and water-laid sediments. Glacial processes and their effects on local geography have attracted the attention of workers since early in the nineteenth century. A current summary of investigations is given by Muller (1965).
Deglaciation took place locally between 14,000 and 12,500 years BP. During ice retreat several Moraines were draped across the land surface as well as across the floor the lakes which preceded Seneca (Figure 1). Many of the moraines formed at the northern boundary of a pro-glacial lake either as shoreline features or at the ice edge beneath a lake surface. Those moraines emplaced on the floor of what was later to be Seneca Lake were subsequently buried by lake sediments.
On this trip we will examine directly and by subbottom profile the sediment on the lake floor as well as those in the immediate subbottom available to a light dredge or piston corer.
Seneca Lake's drainage basin boundary, the lake's major tributaries. the local bedrock geology and the location of moraines are given in Figure 1.
THE TRIP
Our route carries us from the dock at the northeast corner of the lake south to the various sampling locations and back again, a total of about 10 km. (See Figure 2). While underway, we will examine the sub-bottom where possible. At the various locations we will look at bottom sediments collected by Ponar dredge and at the last stop we will examine a sediment core. Since shoreline sediments form such a small fraction of the sediments in the lake basin we will not be concerned with them on this trip.
2014: Trip is by boat, no road log, hence, no stops or views.

A10: AN EXAMINATION OF BOTTOM SEDIMENTS IN SENECA LAKE

A11: ENGINEERING GEOLOGY AT NINE MILE POINT, NEW YORK
Joseph A. Fischer and H. Scott Laird
Dames & Moore, 6 Commerce Drive, Cranford, New Jersey
The south shore of Lake Ontario for some time has been considered well suited for many industries, among them nuclear power plants. Several plants are currently in operation along the lake shore, and plans for others are being seriously pursued.
As a result of the critical nature of the engineering structures which comprise a nuclear power plant, details of the geology, seismicity. and geohydrology of the plant site are defined to an extent generally not achieved in most geotechnical investigations. In addition, there is a lengthy and intensive peer review involved in the licensing process. This review focuses attention upon site details that might be classified ordinarily as unimportant, covered in recommendations as "our experience" or "our judgement", or in some instances, perhaps forgotten. Although we may not be pleased to "overexplain" many details of our analyses, it is difficult to agree that the discipline is not good for the soul and, in addition, that information ordinarily not available to the geotechnical profession is documented for futUre use.
The information presented in this report is an attempt to present the consultant's understanding, although somewhat broadly and generally, of the engineering geology at the Nine Mile Point site, developed through approximately 15 years of study. It is emphasized that much of the detailed and fundamental analyses that are performed ultimately in the process of providing design parameters for the facilities are based upon the parameters presented herein. Obviously, however, the details of all the design analyses are beyond the scope of this discussion. Instead, it is important to emphasize that no matter how sophisticated the analyses, ultimately they are dependent upon precise and detailed geologic data concerning the stratigraphy, structural geology, geohydrology, seismicity, and rock stresses. This presentation focuses upon the importance and relationship of the bedrock stratigraphy to the engineering decisions involved in the design and construction of the nuclear facilities at Nine Mile Point, New York.
2014: No road log, hence, no stops or views.

A11: ENGINEERING GEOLOGY AT NINE MILE POINT, NEW YORK

A12: THE TULLY LIMESTONE OF CENTRAL NEW YORK -STRATIGRAPHY AND FACIES VARIATION
John M. Cubitt
Syracuse, NY
Philip H. Heckel
University of Iowa
Iowa City, IA
Alan G. DelSignore and Michael Wooldridge
The Tully Limestone of central New York is an anomalous sequence of carbonate rocks lying within thick coarse clastic rocks of Devonian age constituting the Appalachian Basin. The thin carbonates are sandwiched between terrigenous detrital rocks thickening westwards from the Catskill Delta and represent a significant change of depositional environments through the Devonian epicontinental seas. The events leading to the development of the Tully Limestone have been described in detail by Heckel (1973) and this field trip is designed to provide a description of the Tully Limestone field relationships studied at Syracuse University within the framework of Heckel's study.

A12: THE TULLY LIMESTONE OF CENTRAL NEW YORK -STRATIGRAPHY AND FACIES VARIATION

View down the Onondaga trough
On the R (SSW) observe the view down the Onondaga trough. This is one of a number of u-shaped glacial valleys characteristic of the area south of Syracuse. As glaciers receded a network of troughs and cross channels were established during the Pleistocene Epoch.

Limestone strata of the Onondaga Fm
On the L in this roadcut observe the gently folded, well-fractured limestone strata of the Onondaga Formation. Stratigraphically this formation lies conformably below the Hamilton Formation upon which the Tully Formation disconformably rests.

Differentially weathered chert layer
Through this roadcut observe the protruding, differentially weathered chert layer in the upper portion of the exposure of this Middle Devonian outcrop.

Lafayette Exit.
The shale outcrop in view is
of the Hamilton Formation.

Tully moraine terminating this trough
On the R observe the etched Tully moraine terminating this trough. It is part of the Valley Heads moraine system and is associated with kame and kettle topography representing a period of stagnation during the retreat of the glaciers in the Wisconsin Glacial Stage of the Pleistocene Epoch. Southward the moraine grades into a pitted outwash plain.

Hamilton shale and siltstones along the northbound lane.

Tree lined kettle
Off to the R (S) observe the tree lined kettle. Along the rest of the route note the gently to steeply rolling terrain and N-S trending glacially deepened valleys.

Lower and Upper Tully Fm on R, location 3c
De Ruyter Reservoir on L, lower and upper Tully Formation outcrop on R (location 3c,

STOP 1. Abandoned Quarry, location 3ab
Turn R onto Coon Rd. on shoulder and park (W. Lake Rd. has become Highbridge Rd.). The abandoned quarry is located in the postglacial stream valley upstream from Highbridge Rd. (location 3ab Heckel, 1973).

Stop 2. Tinker's Falls, location 2ac
Pull off onto shoulder or carefully cross the oncoming lane and park in widened
shoulder area. Tinker's Falls lies upstream from the road; the stream bed is just N of the
parking area across Rt. NY91. (Location 2ac, Heckel,1973)

Lower and upper Tully members, location 1h
The lower and upper Tully members are exposed along the banks of the ravine above the falls seen dead ahead from Sawmill Rd. (Bucktail Falls, location 1h Heckel, 1973).

Recut delta deposits
Viewing the NE shore of Otisco Lake observe the recut delta deposits where post-glacial streams debouche into the lake.

Stop 3. Borodino Mound Complex, location Qys
Borodino Mound Complex. (location Qys, Middle Quarry, Heckel, 1973)

Stop 4. Location 6s
Intersection with Bacon Rd., park on roadside. This last outcrop is approximately 0.7 miles along Bacon Rd. in the 3rd ravine that is crossed. (location 6s Heckel, 1973)

B2: SYRACUSE MELTWATER CHANNELS
B.M. Hand
The channels carved by Pleistocene meltwater through the Syracuse area tell an interesting and complicated story. Their discharge, which rivaled Niagara's, spilled over waterfalls having the plan dimensions of Horseshoe Falls.
Examined in detail, the channels are determined to be products of multiple episodes of cutting, infilling, and re-excavation that collectively span several glacial epochs. The most recent history is complex, because the simple south-to-north activation sequence that has been preferred in the past, turns out to have been impossible. In its place is emerging a new sequence that involves piecemeal flushing of our most spectacular channel, multiple occupation of another, a minor ice readvance in late Pleistocene time, and catastrophic release of water from a large proglacial lake when a lOO-ft drift dam failed.
The purpose of this trip will be to view the topographic features which document an ample flow of quantities of meltwater through the Syracuse area in late glacial time. It will focus, however, on the evidence for reinterpretations of the type previously mentioned. Observation will blend into inference, and inference into speculation. However, sufficient opportunities will be available for challenging the more outrageous claims that your leader, in the end, should not get away with too much sleight-of-Hand.

B2: SYRACUSE MELTWATER CHANNELS

T-intersection with Brighton Ave
At T-intersection with Brighton Ave., view ahead (west) looks across northern end of Onondaga Trough. Downtown Syracuse is two miles to the right, at the north end of Onondaga Trough.

West end of Rock Cut cross channel.
Intersection is at west end of Rock Cut cross channel. Elevation of channel floor (road level) is 550 ft. Floor of Onondaga Trough is at about 400 ft, so depth of Onondaga Trough Lake was 150 ft when this threshold controlled. Approach to Meadowbrook Channel also was through this area. Highway excavations on left briefly exposed the following sequence:
till
flowtill
varved lake clays (about 100 yrs; upper part contorted by ice thrusting)
bedrock (Bertie Formation)
Interpretation: Bedrock was cleared of drift by drainage from Onondaga Trough Lake when Meadowbrook Channel was active. (Western end of Rock Cut was still drift-filled.) Readvance of ice blocked Meadowbrook outlet, raising level of Onondaga Trough Lake from 550 ft to 700 ft, reactivating Nottingham Channel. Lake clays were deposited in this interval. Upward increase in dropstones indicates approach of ice front. Ice over-ride then contorted upper part of clay and deposited flowtill and till. This minor re-advance is thought to have been limited to tongues of ice extending southward into "through" valleys.

Spectacular view of Onondaga Trough.
We are approximately on the shoreline for the lake as it would have been during the Smoky Hollow Stage. The lake was 2 mi wide, 350 ft deep, and extended to the Tully Loop of the Valley Heads Moraine, 13 mi south.

Cut-off meander loop of Smoky Hollow Channel
Cut-off meander loop of Smoky Hollow Channel is on right. Loop surrounds an umlaufberg, 3 mi to the east can be seen the east side of Jamesville Trough, and beyond it (about 8 mi away) the far (east) wall of Fayetteville-Manlius Trough.

Begin descent into Smoky Hollow.

This road follows the main Smoky Hollow Channel.

Loop channel on right.

Umlaufberg on right.

Loop channel returns from right.

Jamesville Reservoir (artificial lake) on left.

View (southward) of Jamesville Trough.

Excellent view of Jamesville Trough.

Crossing southernmost scour-way of Moorehouse Flats.

Moorehouse Flats for next 0.4 mi.
Discharge from Jamesville Trough Lake swept eastward (to right) across this threshold on Onondaga Limestone during the Smoky Hollow Stage.

Jamesville quarry of Allied Chemical Corp
Artificial barrier on left partially hides Jamesville quarry of Allied Chemical Corp, which extends for 1.5 miles along the route. Quarry is in Onondaga and Manlius Formations.

High Bridge Channel / Fayetteville-Manlius Trough
Crossing axis of High Bridge Channel (left) where it enters Fayetteville-Manlius Trough (right).

STOP 1. High Bridge Delta
High Bridge Delta, an expansion bar built where White Lake Channel entered Fayetteville-Manlius Lake. At least the final shaping is attributed to catastrophic discharge which occurred when a 100 ft drift dam failed in Rock Cut Channel. Observe large-scale cross-stratification, clast size (mostly sand and pebble gravel, with larger clasts to 6 ft or more), and clast lithology (dominantly carbonate, but some exotics). Till occurs immediately below a cemented gravel zone in the deeper parts of the quarry.

Climb delta face. Main channel on left.

Road is on top of High Bridge delta (expansion bar)
Road is on top of High Bridge delta (expansion bar), elevation 600 ft. Floor of channel (on left, not clearly visible) is at 530 ft. If the topography here is essentially primary, as it appears, flow in the main channel was 60-70 ft deep during delta construction (Rock Cut flood).

Descend into scour channel
Descend into scour channel maintained by vortex in lee of Rock Cut Delta. The near (northeast) wall of this scour channel is bedrock while the southwest side is the depositional front of Rock Cut Delta.

Bedrock exposures on left.

Bedrock behind houses on right
Bedrock behind houses on right was swept bare by vortex scour.

Dead ahead is slip face of Rock Cut Delta.
Delta forests here consist of pebble gravel, with basal layer of boulders thought to have been emplaced by rolling down the delta face. Some of these boulders are used as yard ornaments.

Cross scour channel and climb delta front.

Boulders 4 to 6 ft long
Here on top of Rock Cut Delta the favored lawn ornaments are boulders 4 to 6 ft long. Most are of local bedrock types, but some are exotics. These boulders occur at an elevation of 600 ft, about 50 ft above the floor of Rock Cut Channel, along which they were transported.

Note the broad, channel-like depression to the left
Note the broad, channel-like depression to the left on the grounds of the Dewitt Fish and Game Club. This scour-way is 700 to 1000 ft wide; its axis lies about 35 ft below the adjacent delta surface and slopes gently westward. i.e., up-current. It is interpreted as having developed during catastrophic discharge from Rock Cut Channel, when water level stood near 500 ft elevation. Presumably, most, if not all, of the delta surface was under water at one time, but scour-ways such as this accommodated a disproportionate part of the flow.

Fluvial boulder gravels in road cut on left.
The valley into which we are now descending was cut subsequent to formation of Rock Cut Delta and so transects the delta, isolating the remnant we have just crossed from other remnants on the west side of Jamesville Trough.

Till in roadcut on left
Till in roadcut on left shows that the flow which sectioned Rock Cut Delta (Rams Gulch phase) cut completely through the delta gravels and into glacial deposits underneath.

STOP 2. Turn left into abandoned gravel pit.
Large boulders near entrance are common constituents of this segment of the Rock Cut Delta. Whether this pit can be examined in detail depends on interstate highway construction and other factors. However, under favorable conditions one can see imbricate boulder gravels and crossbedding that document radial flow from the mouth of Rock Cut. The till surface on which the delta was built forms the floor of the quarry over large areas. The edge of this delta spills northwestward into the mouth of Nottingham Channel, clearly indicating that the flood gravels (which initiated State II of Rock Cut drainage and built most of this delta) are younger than the most recent flow through Nottingham.

Gravels beyond houses on left
Gravels beyond houses on left are part of the delta built by discharge from Smoky Hollow spilling into Jamesville Trough Lake.

STOP 3 and LUNCH. (Parking lot, Clark Reservation.)
From main overlook, observe the steep-walled plunge basin at the west end of Clark Reservation Channel. This dry waterfall, 120 ft high, has plan dimensions nearly identical with those of Horseshoe Falls, which today carries 90 percent of Niagara's discharge. Presumably, the normal flow through Clark Reservation in late Pleistocene time was comparable to that of the present Niagara River. Green Lake, which now occupies the plunge basin, is about 55 ft deep. A second, smaller plunge basin (Dry Lake) is located immediately upstream from the lip of the main falls. Its height was only about 50 ft.

Trailer Park Plunge Basin
Hike from the parking lot north, then west, following park boundary service roads and foot trail to the south rim of Rock Cut Channel. From the overlook one can see the trailer park plunge basin 170 ft below. This was the earlier of two south-wall plunge basins to be active during Phase I of Rock Cut drainage. By this time, drift had been flushed from the east end of Rock Cut, at least to the 600 ft level. The proposed Rock Cut drift barrier was located immediately west of here. The boulder spit partially barring the plunge basin was constructed by catastrophic discharge when the dam failed.

Dramatic view of Rock Cut, looking upstream (west).

Trailer Park plunge basin on left.

Circle park on perimeter road.
Turn right and circle park on perimeter road. (This is private property, so permission should be requested.)
Immediately after turn, note artificially truncated spit on right. Boulder layers dip southward at angle of repose, indicating accretion into plunge basin accompanied lengthwise growth. Original basin form has been modified through removal of talus and addition of about 30 ft of fill.
Boulders have been known to tumble to the base of the talus or slightly beyond, and have caused some concern.

Second (western) plunge basin
On left was location of the second (western) plunge basin which was operative immediately prior to diversion of the flow to Nottingham Channel. The basin has been enlarged by quarrying operations, and effectively destroyed. The ridge immediately south of the road is what is left of the boulder spit, which once completely barred this plunge basin. Its top stands more than 80 ft above the floor of Rock Cut. Some individual boulders exposed during excavation were 8 ft long.

Location of drift barrier
Location of drift barrier which diverted flow to south wall plunge basins, later to Nottingham Channel, and finally failed, releasing the Rock Cut flood.

View into Rock Cut, looking downstream.

STOP 4. Approach to Nottingham Channel
You are parked in the approach to Nottingham Channel. Incision is not obvious because the flow was spread wide. However. much of the bedrock has been scoured free of till, and there remain patches of gravel that were deposited by the meltwater.
Walk NE into the wooded area, to view the plunge basin at the upstream end of Nottingham Channel.

B3: LATE PLEISTOCENE HISTORY OF SOUTH-CENTRAL ONONDAGA COUNTY
David E. Andrews and Richard Jordan
Central New York State offers much for the glacial geomorphologist including examples of both erosional and depositional features associated with the continental ice sheet. Within south-central Onondaga County many of these morphological as well as associated stratigraphic units can be seen. Some pose intriguing problems relating to the chronology of events leading to their birth and subsequent survival. The scope of previous work ranges from broad regional approaches to localized detailed analyses and has been reported in numerous publications and theses (e.g., Blagbrough, 1961; Brainerd, 1922; Durham, 1958; Fairchild, 1899a, l899b, 1905, 1907, 1909, 1932; Grasso, 1970; Kirkland, 1970; Krall, 1966; Muller, 1964; von Engeln, 1921, 1961). The purpose of this report is to furnish the reader with a short and generalized account of late Pleistocene history of southern Onondaga County. This is supplemented with Figure 1, which depicts approximate terminal zones associated with post-Olean glacial advances.

B3: LATE PLEISTOCENE HISTORY OF SOUTH-CENTRAL ONONDAGA COUNTY

Rock Cut channel
Look southeast and observe a steep walled, flat bottomed channel. This is Rock Cut, one of several major meltwater channels which controlled the eastward escape of impounded glacial waters.

Rock Cut channel and Onondaga Trough
To the left (E) is the channel - elev. 550 ft. To the right (W) is Onondaga Trough, elev. of valley floor is approximately 415 ft.

Outcropping of Elmwood Formation
Outcropping of Elmwood Formation; a portion of the scarp developed on Manlius Group.

Drumlinoid of bedrock with veneer of lodgment till.
On right (W) SUNY - College of Environmental Science & Forestry - Experimental Station. On left (E) LaFayette Golf Course located at base of drumlinoid composed of bedrock with thin veneer of lodgment till. This is typical of upland streamlined features of this region.

STOP 1. Entrance - Smoky Hollow Meltwater Channel
Discussion of character of channel and relationship to Onondaga Trough History, including preview of broad deltas visible in valley to southwest.

Cross ancillary channel
Cross ancillary channel developed during initial stages of Smokey Hollow. Elevation of bedrock at junction of this channel and Smokey Hollow is approximately 780 (a depth of 50 ft)

Borings found sand and gravel over till
Borings at this intersection encountered 24 ft of sand and gravel overlying 17 ft of till. No bedrock was encountered.

Water tanks on subdued kamic topography
Note the water tanks positioned on subdued kamic topography; adjacent uplands to south are bedrock controlled.

Note coarseness of till
Cross under Route 181; note coarseness of till. Road on right leads to LaFayette Landfill approximately 1/2 mi to north. It is located in deltaic sediments deposited in a lowering proglacial lake (elevation 1040±)

STOP 2. Stream Cut - Kennedy Creek
On right (W), across stream is bouldery till overlying light brown sands. Beneath this is a red-gray silty clay.

Close-up of bouldery till in roadcut.

Enter small meltwater channel.

Reenter meltwater channel.

STOP 3. Overview Of Tully Moraine
Discussion of its development as well as other prominent glacial features.

Note cemetery on right (w) and gravel pit on left (E).
These are located on a zone of drift tentatively correlated to the Port Huron advance.

STOP 4. Overview Of Rattlesnake Gulf
Discussion of its development and its relationship to the deglaciation of Tully Valley.

Start of Valley Heads Moraine
Start of constructional topography of Valley Heads Moraine (proximal end)

Leave morainal topography
Leave morainal topography and reenter streamline topography.

Outwash plain formed by Valley Heads Ice.
This gradually sloping surface to the south is the outwash plain formed by Valley Heads Ice.

The rolling hills on left (E) are lateral moraines
The rolling hills on left (E) are lateral moraines associated with the "advanced" Valley Heads Ice. The tree line emphasizes the break between the moraine and the bedrock escarpment.

Gradual change into a zone of pitted outwash.

STOP 5. Gravel Pit South Of Green Lake
Examination of features and materials of pitted outwash plain.

Outwash to pitted outwash to kame and kettle
Note the procession from outwash to pitted outwash to kame and kettle topography as the "moraine" is approached.

STOP 6. Allied Chemical Corporation Gravel Pits
Discussion as to mode of origin of the "moraine".

Bedrock crops out on right, valley fill on left

On left (E) kame field grades into kame terrace.
This is believed to reflect one of the positions for the "advanced" Valley Heads Ice.

On right (W), small remnants of lateral moraine.

Lateral moraine on right and continues down valley.
A portion of it has been cut for a parking lot for Song Mountain Ski Resort. Farther south the moraine becomes partially buried by colluvium.

Last vestige of lateral moraine
Last vestige of lateral moraine as it dips under road and into outwash.

Note that slope changes from dipping south to north.
This represents the distal edge of a fan built from Otisco Valley and lies above the Tully Valley outwash.

Classic example of a truncated spur.
On left is von Engeln's (1961) classic example of a truncated spur.

Descent from the terrace cut into outwash gravels.
These were deposited by meltwaters from Valley Heads Ice in Otisco Valley.

Outflow channel and borrow pits
Scarp of outflow channel on right (E); on left (W) two borrow pits which are remnants of the dissected plain. Above these are vestiges of a lateral moraine deposited during "advanced" stage.

To south is a partial ridge across the valley.
It merges with the "advanced" stage lateral moraine on east wall and can be traced northward past Gulf Rd.

On right is a second "advanced" lateral moraine.

The proximal edge of the Valley Heads "moraine".
On the west wall, remnants of a nearly horizontal lateral moraine can be seen. The valley drops over 500 ft to Otisco Lake. Strong Rd. follows the moraine onto the uplands.

Cross high-level meltwater channel
Cross high-level meltwater channel which carried water into Otisco Valley.

STOP 7. Amber Delta
Discussion of its character and mode of origin.

Kames, delta and eroded lake clays
The hummocky terrain is a result of a complex relationship between kames, delta and eroded lake clays. Borings taken at the dam suggest a terminal ice position. This is correlated tentatively with the Port Huron advance.

Red clays exposed in the slump
The red clays exposed in the slump occur throughout this portion of the valley and create many slope stability problems.
Continue along road and observe clay mounds and "moraine" to north.

Kamic topography and morainal features
Observe the kamic topography and morainal features on left (N).

STOP 8. Sand Pit - Masters Rd.
Consideration of the nature and history of the deposit.

STOP 9. Guppy Gulf And Bishop Hill Delta
Further discussion of deglaciation history of the area.

Road cuts through moraine and delta
The road cuts through the moraine near the base of the hill and then transects a delta built into the preglacial lake impounded south of the moraine.

Three minor meltwater channels
Proceeding north, three well-developed minor meltwater channels are traversed. Water flowed from east to west and deposited the above mentioned deltaic sediments.

Till over sand and gravel
Borings and wells in this upland region generally encountered over 50 ft of till overlying a thick layer of sand and gravel.

Note kamic topography on side hill to southeast.
This is associated with small morainal belt which is believed related to a post-Port Huron readvance. The valley in the foreground is the northern extension of the Navarino Meltwater channel which supplied sediments to Amber Delta.

Navarino Channel.

Morainal belt with small meltwater channel
On left (N) is portion of morainal belt mentioned above with small meltwater channel formed between drift and uplands.

STOP 10. Overview Of Cedarvale Deltas
Discussion of large-scale morphological features and generalized history of deglaciation.

Cobble-boulder delta remnant
On left is cobble-boulder delta remnant at elevation 640 ft

Scarp to the right
The scarp to the right is a result of erosion through the deltaic deposits and into the till.

STOP 11. D.W. Winkleman Pit
Examination of a nearly complete late Pleistocene stratigraphic section and discussion about mode of origin for the deltas.

Contorted varved red silts and clays
Contorted varved red silts and clays exposed in stream bank to left (N).

Road continues along 600 ft terrace

Note Onondaga Limestone outcropping.
This forms a ledge along the east wall of the valley.

Large sand and gravel pit
On left (W) is large sand and gravel pit excavated into kame terraces. To the right (E) is a thin veneer of sand and gravel over the limestone ledge.

Note broad bedrock flexures
Note broad bedrock flexures related to the stresses imposed during the Appalachian Orogeny (Chute, 1964).

B4: PUNCTUATED AGGRADATIONAL CYCLES (PACS) IN MIDDLE ORDOVICIAN AND LOWER DEVONIAN SEQUENCES II
Continuation of trip A8

B4: PUNCTUATED AGGRADATIONAL CYCLES (PACS) IN MIDDLE ORDOVICIAN AND LOWER DEVONIAN SEQUENCES II

STOP 4. Munnsville Quarry
Nine Helderberg cycles (PACS) are exposed in the Munnsville Quarry (Fig.9), four in the Olney-Elmwood, one equivalent to the Clark Reservation, four in the Jamesville and two (plus a partial cycle) in the Deansboro. The first four PACS contain restricted subtidal micrites grading upward into supratidal laminites. The four cycles in the Jamesville are defined by gradation from argillaceous limestones up into purer bioturbated limestones deposited in restricted subtidal conditions. The two complete Deansboro cycles, like those at Jordanville, grade from bioturbated shelf deposits.

STOP 5. Warlock-Perryville Quarry
The lower Helderberg Croup (Thacher-Jamesville) is well exposed at the north end of the quarry and the upper part (Jamesville-Deansboro) at the south end. Figure 10 is an outline of the stratigraphy of the lower Helderberg (north quarry face) with cycle analysis present up through the Clark Reservation. The section in the south quarry overlaps the top of the north section and within the complete Jamesville and Deansboro at least five cycles are present (Fig.11). Cycles IX and XI, the first and third Jamesville cycles, begin in bioturbated argillaceous calcarenite which grades up into cleaner more current-stratified calcarenites. Cycle X, is a stromatoporoid-laminite cycle like those seen early at Jordanville and Munnsville. Cycle XII, a thin current-stratified deposit bounded by two erosion surfaces, is genetically distinct. This cycle may represent the remains of a barrier, the lower erosion surface having been cut by a migrating tidal inlet, the upper by a ravinement.

B6: MOSS ISLAND, LITTLE FALLS, NEW YORK
H. S. Muskatt
Utica College
Utica, NY
"I consider this Island and its potholes so unique that I have recommended it most highly for inclusion in the registry of Natural Landmarks of the National Park Service. This island should not be touch in any way or the value of the potholes would be diminished" (Morisawa, 1977, p. G-41).
"Moss Island merits protection and preservation as a geological landmark." (Muller, Hawley, and Muskatt, 1977, p. G-8).
In May, 1976, Moss Island was declared a National Natural Landmark. It is one of only four hundred such registered natural treasures in the United States.
Plans for construction of a highway across Moss Island by the N.Y.S. Department of Transportation were initiated in 1968. Opposition to the proposed plan arose in 1973 only after some concerned individuals found out about those plans. In the forefront of that battle were the Mohawk Valley Floodplain Association, a local group concerned with the Mohawk River and the Utica chapter of the Izaak Walton League, a national conservation organization. These two organizations requested assistance from the New York State Geological Association in 1974. Through the efforts of these organizations, among many others, as well as individuals, national landmark status was achieved. Nevertheless, even with the granting of such status the N.Y.S. D.O.T. continued to press for construction over the Island. The D.O.T. stand was taken over the objections of such groups as the N.Y.S. Department of Environmental Conservation, National Park Service, Sierra Club. N.Y.S. Office of Parks and Recreation, and the National Audubon Society. Not until the Secretary of the U.S. Department of the Interior strongly recommended against approval of the application to the Coast Guard did the N.Y.S. D.O.T. "gracefully" back down. Disapproval by the Coast Guard was on environmental grounds.
GENERAL GEOLOGY
Moss Island (Fig. 1) is a 14-acre curved, dumbell-shaped feature lying between the Barge Canal to the south and the Mohawk River to the north. Generally the eastern part of the island is referred to as Moss Island. It lies on a horst which raised the Precambrian gneiss to its present position. The throw of the fault is considered to be about 850 ft (Cushing, 1905, p. 40). Isachsen and McKendree (1977) indicate a throw of 250 ft.
Bedrock of the island is a quartzose syenite gneiss of Precambrian age. Potholes and related hydraulic abrasion features, prominently displayed on the island, document the torrent of early postglacial drainage from the Great Lakes through the Mohawk Valley. For some 1000 yrs. from about 12,000 to 11,000 yrs ago (Lake Iroquois phase), the Mohawk River carried the entire outflow of the Great Lakes while the St. Lawrence valley was blocked by the slowly receding continental ice sheet. The resistant uplifted syenite gneiss here at Little Falls created the preglacial divide between the Hudson and St. Lawrence drainages. As the waters from the Great lakes poured over this divide the narrow valley at Little Falls was cut. These same rapid swirling waters helped create the spectacular potholes on the island. The potholes were reported first by Vanuxem (1842, p. 209).
2014: Highways are now totally different in Little Falls, so route has been adjusted.

B6: MOSS ISLAND, LITTLE FALLS, NEW YORK

View of Onondaga Valley
Looking W, straight ahead, view of Onondaga Valley, a N-S glacial trough.

View of downtown Syracuse on left.

Route I690 follows a glacial meltwater channel
Route I690 follows a glacial meltwater channel, the Erie Canal Channel. The floor of this channel is depositional (Muller, 1964, p. 51).

Route cuts through the Lake Iroquois glacial lake plain
Route cuts through the Lake Iroquois glacial lake plain whose outlet was at Rome, NY. This is part of the Ontario Lowland and is underlain by Middle and Upper Silurian units.

Northern limit of the Appalachian Plateau
View to the right (S), first good view of the northern limit of the Appalachian Plateau. Plateau units here are of Late Silurian age and principally the Vernon Formation and the Syracuse Formation, along the face of the scarp.

Ancient glacial lake barrier bars
Low ridges to right (S) and left (N) are ancient glacial lake barrier bars. Additional bars will be seen along route

Another view of Appalachian Plateau front on your right.

Outcrop of Middle Silurian Oneida Conglomerate
Outcrop of Middle Silurian Oneida Conglomerate, basal formation of the Clinton Group on your right (S) alongside roadway.

Another view of Appalachian front on right.

Recent Oneida Lake plain to left
Recent Oneida Lake plain to left (N) with view of the foothills of the Adirondacks in distance. Oneida Lake is a remnant of glacial Lake Iroquois.

View of the foothills of the Adirondacks ahead.

Riverside Airport on right (S).
2014: Airport is gone, but can still be seen on 1997 Google Earth photo.

UTICA on right.
My residence and the location of UTICA COLLEGE of Syracuse University.

Travel along a higher floodplain of ancient Mohawk River.

We are located in the Mohawk subprovince.
View to the right is again the northern limit of the Appalachian Plateau. The horizontal benches seen in the upper half of the scarp are of Middle Silurian sandstones and conglomerates of the Clinton Group. The Clinton Group disconformably overlies the mudstones and siltstones of the Frankfort Formation of lower Late Ordovician age which occur in the lower portion of the scarp.

View of the Adirondack foothills on the left (N).

Traveling on an old terrace of the Mohawk River.
Present Mohawk River floodplain seen on right (S).

Terraces cut into Middle Ordovician Utica Formation
View on left (N), terraces cut into Middle Ordovician Utica Formation to control slumping of slope. Every several years the shaley mudstone slumps, thereby blocking the highway for a day or two. Because of the regional dip, 50-80 ft/mi to the south (right), the Utica Formation is not exposed across the valley to the right (S). The overlying unit, the Frankfort Formation does crop out.

View on left (N), another exposure of terraced Utica shale.
Remington Arms plant on your right (S), in valley.

Terminal moraine of the Ontarian lobe
View across valley to right (S) of knobby hills representing the terminal moraine of the Ontarian lobe which moved from the west. This is the easternmost limit of the last glacial advance in this region (Dunn, 1960, p. D9).

A large gravel pit of glaciofluviatile origin.
View on the left (N). A large gravel pit of glaciofluviatile origin. The foreset beds are clearly shown. Being the top elevation of the deltaic deposit is about 520 ft, Fairchild (1912, p. 39) would assign it to post-glacial Lake Amsterdam.

Block of tillite on right (S).

Old stone Fort Herkimer Church on left (N)
Old stone Fort Herkimer Church on left (N) completed in 1767. Listed on National Register of Historic Buildings in 1972.

Glacial till on right.

View of Middle Ordovician Dolgeville Formation.
Look quickly down on right. View of Middle Ordovician Dolgeville Formation.

STOP 1. Outcrop of Late Cambrian Little Falls Dolostone.
This unit directly underlies the Black River Group in this area. It nonconformably overlies a Precambrian syenite gneiss. The nonconformable contact will be seen at Stop 2. The gneiss may be examined on Moss Island in Little Falls, Stop 5.
The Little Falls Dolostone is a sandy, medium-grained dolostone with some sandstones occurring near the base of the unit. Except for the abundant colonial algae Cryptozoon, the unit seems to be barren in this area.

Cliffs of Little Falls Dolostone on the right (E).

STOP 2: (15 min - picture stop).
Parking lot on left. Walk down hill (W) and cross road to
empty lot on west side of church. Walk to fence in back center of lot. Across abandoned railroad right-of-way observe non-conformable contact of Little Falls Dolostone overlying Precambrian syenite gneiss. Dolostone is overlain by classic manmade limestone wall.

STOP 3: (15 min -picture stop).
Park in clearing across the road, north side. CAUTION crossing road. Walk back across the road CAREFULLY. Observe potholes on northeastern end of Moss Island across Mohawk River. This view is similar to that shown in Lobeck (1939. p. 194). The potholes will be seen close up at Stop 5, our last stop on this trip.

St. Mary's Church on left.
Park on right, before turn, displays several small roches moutonnees.

STOP 4: (15 min picture stop).
In front of apartment house at 550 Alexander St. Large well-rounded boulder on front lawn was found in a pothole during excavation of the foundation of the building. This is a typical boulder used as an abrasion tool by the swirling waters for the creation of potholes.

STOP 5: End of trip.
Lock 17 is one of the highest lift locks in the world, 40.5 ft. The lower level is 322.5 ft above sea-level and the upper level is 363.0 ft above sea-level. For those who are interested, after we have examined the potholes, you can visit the old Erie Canal lock constructed about 1825. This old lock is located southeast of the existing Lock 17. It may be reached by walking across the catwalk in front of the eastern end of the lock and then down the stairs. The old Erie Canal lock is just a short walk to the east.
Part of the proposal involving construction of the bridge over Moss Island included covering the old lock. As stated by one local supporter of the bridge, "burying the old Erie Canal lock thus preserves this historic site for posterity".
Several potholes are located west of the parking area, along the south facing cliff adjacent to the road.
Walk north from parking area several yards along path to clearing, an old picnic area. Note iron rings in the gneiss. These rings are said by some to have been used as pole support tiedowns for: (1) telephone poles, (2) "A" frames as part of the lock construction, (3) eyelets for hawsers for hauling barges. Perhaps, on the other hand, they may have been used by Rip Van Winkle's friends as croquet wickets when they tired of bowling in the Catskills.
Walk NNW about 200 yds across the island and then turn N, downhill to potholes. STAY ON PATH and WATCH OUT for WIDE JOINT OPENINGS which require a slight jump. Paint marks represent bridge positioning.
The ecological balance here is critical, the soil cover is thin. DO NOT pick flowers or destroy foliage. Most of the low-lying bushes are blueberry bushes. You may eat in season. Most of the plant species seen here are characteristic of Adirondack flora.
Along most of the northeastern margin of Moss Island, facing the Mohawk River, numerous potholes occur. Although several hundred potholes are reputed to be scattered about the island the trip will observe only the area of greatest concentration. The deepest hole measured to the river silt-sand fill is 30 ft. The maximum diameter measured is about 20 ft.
USE EXTREME CAUTION while moving about. Please do not sit on THE THRONE.
The bedrock here is a quartzose syenite gneiss of Precambrian age. A number of quartz-rich dikelets cut across the relatively horizontal foliation of the gneiss. The dikelets generally strike east-west and dip 45°N. According to Cushing (1905), p. 15), the gneiss consists "mainly of feldspar, always show some quartz, usually from 5% to 15% of the rock in quantity, and usually have only a small content of dark minerals, magnetite, hornblende, pyroxene and black mica." The gneiss on the north side of the island is relatively fine-grained whereas on the south side, near the barge canal, it is more coarse-grained and in places seems to be porphyroblastic, occasionally showing augen structure. Several faults also are present.

B7: BIOSTRATIGRAPHY AND PALEOECOLOGY OF THE UPPER DEVONIAN ITHACA FORMATION NEAR CORTLAND, NEW YORK
Jonathan W. Harrington
Geological Consultant
Groton, New York
and
W. Graham Heaslip
State University College at Cortland
Cortland, New York
It is particularly appropriate that we examine the Ithaca Formation in the Cortland area during the Golden Anniversary Meeting of the New York State Geological Association. The rocks of this region are of considerable historical interest, having received attention since the earliest days of geological investigation in New York State. In fact, the presence of fossil shells in the Devonian rocks of New York was first noted in 1751 at a hillside outcrop in Cortland County by John Bartram, a member of the Lewis Evans Onondaga expedition (Wells, 1963).
The New York Devonian is unique in its completeness, fossil content. numerous outcrops, and relatively undisturbed nature. It is the standard reference section for North America and displays a classic example of facies transition. Stratigraphic and paleontologic investigation over the past century has produced a wealth of information, but "Despite this, perhaps another century of rigorous study will be required before a thorough understanding of its paleontology, lithology, stratigraphy and paleoecology can be attained." (Rickard. 1964).
The early stratigraphic work in the Upper Devonian of New York was done mainly by James Hall. J. M. Clarke. and H. S. Williams between 1840 and 1915. These workers subdivided the succession, described the faunas and attempted to correlate along the strike. Due to complex interfingering of the argillaceous western sequence with the thicker arenaceous eastern sequence, correlations proved difficult. Only in the 1930's with the work of Chadwick (1935) did it become apparent that the major facies had migrated across the basin of deposition as the Catskill Delta prograded.
Since 1942 investigation of the Upper Devonian has emphasized physical stratigraphy. The works of Sutton, J. F. Pepper, W. deWitt, Jr. and G. W. Colton have outlined the stratigraphy of the Senecan Series. The cyclic repetition of widespread black shales in western New York has been used to subdivide the succession. Paleontologic studies have, until recently, consisted of clarification and classification of forms originally described by Hall and Clarke between 1847 and 1915. The rarity of new discoveries testifies to the accuracy of their monumental works.

B7: BIOSTRATIGRAPHY AND PALEOECOLOGY OF THE UPPER DEVONIAN ITHACA FORMATION NEAR CORTLAND, NEW YORK

STOP 1. Outcrop in Homer Gulf on Rte. 41A
Ponticeras perlatum has been identified from exposures in Homer Gulf. This places the section in the lower portion of the Ithaca formation, probably correlative with the Renwick shale member. The lithology is extremely variable; consisting mainly of gray and reddish shales and siltstones. The fauna contains elements of both the Warrenella and Ithaca biotopes. Particularly common are: Conularia, Plumularia, Mucrospirifer, Hadrorhynchia, Cupularostrum eximia, Taxocrinus and linguloid brachiopods.

STOP 2. Roadcut on Rte. 13, just east of Dryden
This exposure in the lower Triphammer member is one of the most richly fossiliferous outcrops of the Ithaca formation. It contains abundant encrusting epifauna representing an admixture of biotopes, with incursions of the Ithaca biotope from the west and the Tropidoleptus from the east. Diversity is at a maximum, with maximum size development of Leiorhynchus mesacostale, Atrypa reticularis and Platyrachella mesastralis. Other common fossils are : Hadrorhynchia solon, Porcellia nias, Mucrospirifer posterus and Cyrtina hamiltonensis.

STOP 3. This locality will be an optional stop
The sequence of shales and siltstones is the source of several of the rarer fossils found in the Ithaca Formation, including the scyphomedusan, Plectodiscus cortlandensis and the trace fossil, Tomaculum problematicum.

STOP 4. Road cut on Rte. 81, 3 miles south of Cortland.
This exposure represents the Grammysia biotope in nearshore delta-front sands. Lithology is highly variable with shales, ripple-marked and cross-laminated siltstones and fine sandstones. Coquinite lenses, especially with Cupularostrum, are frequent and usually show distinct size-sorting and differential accumulation of valves. Areas of high currents are dominated by the infaunal filter-feeder, Grammysia, and the byssally attached bivalve, Goniophora. Occasional vertical burrows may be seen.
Sheltered areas support an abundant epifauna of crinoids (Decadocrinus and Acanthocrinus) and occasional brachiopods. This environment is characterized by the accumulation of plant fragments and orthoconic cephalopods, and by the high incidence of carnivores and scavengers -- the gastropods, Pleurotomaria and Loxonema, several asteroids (Urasterella, Lepidasterella) and ophiuroids.
The orientation of many of the smaller crinoid calices (inverted with free arms outspread) indicates very slight water agitation. However the preservation of fragile specimens such as asteroids and the scyphomedusa, Plectodiscus cortlandensis, required periodic rapid sedimentation. Fecal material is occasionally found at this outcrop. It has tentatively been identified as Tomaculum problematicum, a form not previously reported in North America.

STOP 5. Roadcut on Rte. 81 at Homer, Cortland County.
The sequence here consists of alternating dark shales and fine siltstones, occasionally ripple-marked. The sparse fauna, representing the Leptodesma or Grammsia biotope, consists of rare brachiopods and occasional crinoids Acanthocrinus). At several horizons there are colonies of the hexactinellid sponge, Actinodictya placenta. These fragile forms were almost certainly preserved in situ.
Small hillside quarries immediately north of this exposure have yielded Ponticeras perlatum, indicating a correlation with the lower portion of the Ithaca Renwick or Six-Mile Creek Members) in the Ithaca meridian.