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Geologic units in New Jersey (state in United States)

[Additional scientific data in this geographic area]

Hornblende-Plagioclase Gneiss (Middle Proterozoic) at surface, covers < 0.1 % of this area
Hornblende-Plagioclase Gneiss - White- to gray-weathering, greenish-gray, medium-grained, moderately well foliated gneiss containing hornblende, clinopyroxene, plagioclase and trace amounts of apatite, titanite and opaque minerals.
Lithology: gneiss
Englishtown Formation (Upper Cretaceous, lower Campanian) at surface, covers 2 % of this area
Englishtown Formation - Sand, quartz, fine- to coarsegrained, gravelly, massive, bioturbated, medium- to dark-gray; weathers light brown, yellow, or reddish brown, locally interbedded with thin to thick beds of dark clay. Abundant carbonaceous matter, with large lignitized logs occur locally, especially in clay strata. Feldspar, glauconite, and muscovite are minor sand constituents. Sand is extensively trough crossbedded particularly west of Mount Holly, Burlington County. In a few places in the western outcrop belt, trace fossils are abundant, typically the burrow Ophiomorpha nodosa. Unit is pyritic, especially in the carbonaceous-rich beds where pyrite is finely disseminated grains or pyritic masses as much as 0.6 m (2 ft) in diameter. Lowest part of unit is a massive sand that contains small to large, soft, light-gray siderite concretions. The Englishtown underlies a broad belt throughout the map area and ranges from about 45 m (148 ft) thick in the northern part of the central sheet to 30 m (98 ft) thick in the western part of the central sheet to 15 m (49 ft) in the southern sheet. Best exposures occur along Crosswicks Creek in the Allentown quadrangle and along Oldmans Creek. The basal contact with the underlying Woodbury Formation or Merchantville Formation is transitional over several meters. The age of the Englishtown in outcrop could not be determined directly but was inferred from stratigraphic position and pollen content. Wolfe (1976) designated the microflora of the unit as Zone CA4 and assigned it to the lower Campanian.
Lithology: sand; clay or mud
Monazite Gneiss (Middle Proterozoic) at surface, covers < 0.1 % of this area
Monazite Gneiss - Buff-weathering, light-greenish-gray to greenish-buff, fine- to medium-grained, moderately well-foliated, well-lineated gneiss composed of microcline microperthite, quartz, oligoclase, biotite, and monazite. Accessory minerals include hornblende, zircon and opaque minerals. Mapped in Fox Hill Range area
Lithology: gneiss
Amphibolite (Middle Proterozoic) at surface, covers 0.4 % of this area
Amphibolite - Gray- to grayish-black, medium-grained amphibolite composed of hornblende and andesine. Some phases contain biotite and (or) clinopyroxene. Ubiquitous and associated with almost all other Middle Proterozoic units. Some amphibolite is clearly metavolcanic in origin, some is metasedimentary, and some appears to be metagabbro.
Lithology: amphibolite
Albite-Oligoclase Granite (Middle Proterozoic) at surface, covers < 0.1 % of this area
Albite-Oligoclase Granite - White-weathering, light-greenish-gray, medium- to coarse-grained granite composed of albite or oligoclase, quartz, and sparse amounts of hornblende or clinopyroxene. Petrogenetically related to quartz-oligoclase gneiss (Ylo) but Yla has a more granulitic texture. Includes small bodies of pegmatite not shown on map.
Lithology: granite; pegmatite
Preakness Basalt (Lower Jurassic) at surface, covers 1.0 % of this area
Preakness Basalt - Basalt, coarse-crystalline, very dark greenish gray to black. Texture is subophitic; plagioclase and augite crystals are nearly equal in size; no fine-grained groundmass. Plagioclase (An55-60) is subhedral, mostly 0.2 to 0.3 mm (0.008-0.012 in) long, with a few crystals up to 2 mm (0.08 in) long. Clinopyroxene and orthopyroxene grains are equant, mostly anhedral, 0.3 mm (0.012 in) average diameter. Iron-titanium oxides are mostly interstitial, 0.2 to 0.5 mm (0.008-0.02 in) in diameter. Thickness of unit is unknown in Sand Brook syncline.
Lithology: basalt
Passaic Formation Sandstone and Siltstone facies (Lower Jurassic and Upper Triassic) at surface, covers 2 % of this area
Passaic Formation Sandstone and Siltstone facies - Sandstone (JTrps) is interbedded grayish-red to brownish-red, medium- to fine-grained, medium- to thick-bedded sandstone and brownish-to-purplish-red coarse-grained siltstone; unit is planar to ripple cross-laminated, fissile, locally calcareous, containing desiccation cracks and root casts. Upward-fining cycles are 1.8 to 4.6 m (6-15 ft) thick. Sandstone beds are coarser and thicker near conglomerate units (JTrpcq, JTrpcl). Maximum thickness about 1,100 m (3,610 ft).
Lithology: sandstone; siltstone
Passaic Formation Mudstone facies (Lower Jurassic and Upper Triassic) at surface, covers 2 % of this area
Passaic Formation Mudstone facies - Sandy mudstone (JTrpms) is reddish-brown to brownish-red, massive, silty to sandy mudstone and siltstone, which are bioturbated, ripple cross-laminated and interbedded with lenticular sandstone. To southwest where similar lithologic units also occur, they have not been mapped separately, but have been included in undivided unit JTrp.
Lithology: fine-grained mixed clastic; siltstone; sandstone
Magothy Formation (Upper Cretaceous, middle and lower Santonian) at surface, covers 2 % of this area
Magothy Formation - Sand, fine- to coarsegrained, locally very gravelly (pebbles less than 1.3 cm (0.5 in) in diameter) especially in updip areas, typically cross stratified, massive, horizontally bedded, light-gray to white, carbonized wood (several centimeters long) and colorless mica scattered throughout. Black to dark-gray, very carbonaceous clay is locally interstratified with the sand. No calcareous fossils were recovered from the Magothy Formation in the shallow subsurface. In the Freehold drillhole the thin basal bed of the Magothy is composed of quartz gravel (maximum clast diameter, about 2.5 cm (1 in)). The lower part of the formation above the gravel consists of thin-bedded white clay interbedded with fine- to coarse-grained, poorly sorted, thickbedded, light-colored, somewhat micaceous quartz sand. The interbedded clay becomes dark gray up section and the sand is slightly glauconitic and locally shelly. Quartz is the major sand mineral. Siliceous rock fragments, mica, and feldspar are minor constituents. In general, this formation appears to be fluvial near the base (upper delta plain) and gradually becomes more marine upward (shelf). The overall sedimentologic pattern suggests a net transgression during deposition of the Magothy with shelf deposits overriding a nonmarine (probably deltaic) facies. Downdip at Buena, Atlantic County, the Magothy is 22 m (72 ft) thick and is primarily a massive to finely laminated, dark-gray, woody clay-silt. Unit is as much as 55 m (180 ft) thick in the northern part of the central sheet and generally thins to the southwest. The age of the Magothy is best defined by pollen. Christopher (1979) placed this palynoflora in his Zone V of early and late Santonian age. He also recognized three assemblage zones within Zone V, the Complexiopollis exiqua-Santalacites minor Zone (lowest), the ?Pseudoplicapollis longiannulata-Plicapollis incisa Zone (middle), and the ?Pseudoplicapollis cuneata-Semioculopollis verrucosa Zone (highest). All three zones are present in the Magothy in New Jersey. The foraminifera Marginotruncana marginata and Rosita fornicata were collected from the Island Beach corehole at 550 m (1804 ft) and are indicative of the Dicarinella asymmetrica Zone. Because of the overall character of the foram assemblage it is probable that these fossils indicate a late Santonian rather than early Campanian age (H.J. Dowsett, written commun., 1992). The Magothy, therefore, is Santonian or older in age.
Lithology: sand; clay or mud; gravel
Wantage Sequence (Middle Ordovician) at surface, covers < 0.1 % of this area
Wantage Sequence (Monteverde and Herman, 1989) - Restricted, discontinuous sequence of interbedded limestone, dolomite, conglomerate, siltstone, and shale. Upper part is medium-yellowish-brown- to olive-gray-weathering, medium- to dark-gray, very fine to fine-grained, laminated to massive limestone and dolomite that grade down into underlying clastic rocks of lower part. Upper part locally absent. Lower part ranges from grayish-red, medium-gray, pale-brown, and greenish-gray to pale-green mudstone and siltstone containing disseminated subangular to subrounded chert-gravel, quartz-sand lenses, and chert-pebble conglomerate. Lower contact unconformable. Thickness ranges from 0 to 46 m (0-150 ft).
Lithology: limestone; dolostone (dolomite); conglomerate; siltstone; shale; chert
Hornblende Granite (Middle Proterozoic) at surface, covers 2 % of this area
Hornblende Granite - Pinkish-gray- to medium-buff-weathering, pinkish-white or light-pinkish-gray, medium- to coarse-grained, gneissoid to indistinctly foliated granite and sparse granite gneiss composed principally of microcline microperthite, quartz, oligoclase, and hornblende. Some phases are quartz syenite or quartz monzonite. Includes small bodies of pegmatite and amphibolite not shown on map. U-Pb age approximately 1,090 Ma (Drake and others, 1991b).
Lithology: granite; paragneiss; quartz syenite; quartz monzonite; pegmatite; amphibolite
Potassic Feldspar Gneiss (Middle Proterozoic) at surface, covers 0.4 % of this area
Potassic Feldspar Gneiss - Light-gray- to pinkish-buff-weathering, pinkish-white to light-pinkish-gray, fine- to medium-grained, moderately foliated gneiss and lesser amounts of granofels composed of quartz, microcline, microcline microperthite and local accessory amounts of biotite, garnet, sillimanite, and opaque minerals.
Lithology: paragneiss; granofels
Navesink Formation (Upper Cretaceous, Maastrichtian) at surface, covers 0.7 % of this area
Navesink Formation - Sand, glauconite, medium-grained, clayey and silty, massive, dark-gray to dark-gray-green, extensively bioturbated, locally contains large calcareous shells; sand-size mica, locally abundant; weathers light brown or red brown. Basal quartz sand is fine- to coarse-grained, pebbly, massive, light-yellow, and somewhat glauconitic, as much as 2 m (7 ft) thick and formed by the reworking of the underlying Mount Laurel Formation (Owens and others, 1977). Exogyra costata and the belemnite Belemnitella americana occur in the basal quartz sand. Crops out in a narrow belt throughout map area. Fresh exposures occur along tributaries of Raccoon Creek near Mullica Hill, Gloucester County. The Navesink is 3 to 7.5 m (10-25 ft) thick. The Navesink and Red Bank deposits represent a transgressive (Navesink)-regressive (Red Bank) cycle of sedimentation (Owens and Sohl, 1969). The cycle is unconformity-bounded at top and bottom. Within the cycle, the formational contact is gradational. The age of the Navesink was determined from both the macrofauna and microfauna. Planktic foraminifera from the lower part of the Navesink are indicative of the Rugotruncana subcircumnodifera Subzone of early Maastrichtian age (Smith, in Owens and others, 1977). The upper part contains the mollusks Exogyra costata, Sphenodiscus lobatus, and Pycnodonte vesicularis indicating a middle to late Maastrichtian age. Planktic foraminifera from the upper part represent the Gansserina gansseri Subzone of middle Maastrichtian age (Smith, in Owens and others, 1977). Pollen in the Navesink and Sandy Hook Member of the Red Bank are similar; the Navesink microflora is a CA6/MA-1 Zone in Wolfe's (1976) classification. The Navesink, therefore, ranges from early to late Maastrichtian. Sugarman and others (1995) assigned a middle Maastrichtian Zone CC 25 to the Navesink.
Lithology: sand; clay or mud; silt
Quartz-Oligoclase Gneiss (Middle Proterozoic) at surface, covers 2 % of this area
Quartz-Oligoclase Gneiss - White-weathering, light-greenish-gray, medium- to coarse-grained, moderately layered to indistinctly foliated gneiss and lesser amounts of granofels composed of quartz, oligoclase or andesine, and, locally, biotite, hornblende and (or) clinopyroxene. Contains thin amphibolite layers.
Lithology: gneiss; granofels; amphibolite
Belleplain Member of the Kirkwood Formation (middle Miocene, Serravallian) at surface, covers 2 % of this area
Belleplain Member - New member named for a corehole at Belleplain State Forest headquarters (Belleplain II). A thin gravel bed, containing gravel up to 1 cm (0.4 in) in diameter, is present along the contact with the underlying Wildwood Member. The gravel is mainly quartz with small amounts of phosphatized vertebrate remains and sharks teeth. The lower 10.5 m (34 ft) is massive to horizontally laminated, very diatomaceous, dark-gray clay or silty clay with common, small, thin-walled mollusks. This basal clayey unit is overlain by as much as 23 m (75 ft) of mostly sand. The lower 1.2 m (4 ft) of fine- to medium-grained, dark-gray, woody sand is interbedded with clay. These grade up into a fine- to medium-grained, massive, rarely crossbedded, medium- to dark-gray, micaceous, bioturbated, quartz sand. The sand in the upper 10.5 m (34 ft) of this interval becomes coarser grained and is extensively stained gray brown by humates. Sand in the Belleplain is mostly quartz with a minor amount of siliceous rock fragments. Potassic feldspar is a common constituent but typically is less than 10 percent of the sand fraction. The upper 10 m (33 ft) is finely laminated, dark-gray clay with common, thin interbeds of fine- to medium-grained, micaceous quartz sand. Flaser bedding is common in this upper clayey unit. Gamma-ray values are high for the clayey unit at the base (transgressive deposits) and low for the sandy unit above (regressive deposits). This high-low couplet is a distinctive gamma-ray pattern that is typical of most marine units in the New Jersey Coastal Plain (unconformity-bounded sequences that represent an asymmetric transgressive to regressive cycle of sedimentation). The Belleplain is restricted to the southern bedrock sheet and generally occurs in the subsurface except where younger Pleistocene units have deeply entrenched through the overlying Cohansey Formation and exposed it. The Belleplain is greater than 100 m (338 ft) thick along the coast from Strathmere, Cape May County, to Cape May, Cape May County. The age of the Belleplain was determined by using a combination of different fossil types. Andrews (1988) considers the diatom assemblage of Actinoptychus marylandicus, Coscinodiscus lewisianus, Delphineis angustata, D. novaecaesaraea, D. penelliptica, Rhaphoneis clavata, R. gemmifera, and R. scutula to be characteristic of East Coast Diatom Zone (ECDZ) 6 or Bed 15 (equivalent to the uppermost part of the Calvert Formation of the Chesapeake Bay region). Silicoflagellates recovered from the Belleplain include Corbisema triacantha, Distephanus crux crux, and D. stauracanthus. The co-existence of the diatom Coscinodiscus lewisianus with the silicoflagellate Distephanus stauracanthus indicates an age of 13.2 to 12.3 Ma (David Bukry, written commun., 1990). Strontium-isotope ages of the shells range from 14.7 to 12.3 Ma and confirm the paleontologic middle Miocene age. Pollen assemblages from the base of this formation in the Belleplain I core contain spruce, pine, oak, hickory, and poplar (all abundant) with black gum, sweet gum, maple, birch, and Myrica (all sparse). Exotics include Clethra, Cyrilla, Engelhardia/Momipites, Planera, Podocarpus, and Symplocos. This assemblage is a mixture of cooltemperate forms (spruce) and warm-temperate forms (oak, hickory, and exotics; a lowland assemblage). The pollen assemblage in the upper part of the formation lacks the cool-temperate elements and is, overall, a warm-temperate microflora, thus indicating a general warming of the climate during the time of deposition
Lithology: alluvium
Vincentown Formation (upper Paleocene, Selandian) at surface, covers 1 % of this area
Vincentown Formation - Upper part, sand, glauconite (35-40 percent) and quartz (60-65 percent), fine- to very fine grained, very clayey and silty, massive, dark-gray, bioturbated, very micaceous. Lower part, sand, massive, less micaceous and clayey, dark-gray-green. The lower 4.5 m (15 ft) of the formation is a fine- to medium-grained, clayey glauconite sand. Locally, there is an accumulation of disarticulated calcareous shells along the contact with the underlying Hornerstown Formation. These shells are commonly the brachiopod Oleneothyris harlani or the mollusk Gryphaea dissimilaris. Where the shell bed is absent it is difficult to separate glauconite sand of the basal part of the Vincentown from the underlying Hornerstown Formation, which also is a glauconite sand. Gamma logs through this interval show that there is a small gamma spike along the contact between the glauconite sands. The grain size decreases and the formation is significantly more clayey downdip. At Allaire State Park, Monmouth County (drillhole Allaire-C), for example, the bulk of the Vincentown is a clayey, very micaceous, dark-gray, slightly feldspathic quartz sand. Large fossils, which are abundant in the near-surface beds, are absent. In addition, the basal glauconite beds tend to thicken somewhat downdip. Farther basinward, the bulk of the formation is an unfossiliferous, gray-green to locally tan clayey silt or silty clay. Locally, a thin- to thick-bedded glauconite sand occurs at the base. In the thickest downdip section penetrated at Island Beach, the Vincentown is mostly a pale-gray to dark-gray clay-silt. No megafossils were observed in the Island Beach core. On the basis of geophysical log interpretations in the deepest subsurface, this unit has a maximum thickness of about 38 m (125 ft). The age of the Vincentown is best indicated by calcareous nannofossils, which indicate Zones NP 5 to NP 9 (Bybell, 1992). Common nannofossils from Zone NP 5 are Chiasmolithus bidens, Ellipsolithus distichus, Fasciculithus tympaniformis, Scapholithus fossilis, and Toweius eminens. Common nannofossils in Zone NP 9 are Biantholithus astralis, Chiasmolithus bidens, Discoaster multiradiatus, D. salisburgensis, Fasciculithus involutus, F. schaubii, F. thomasii, and Lophodolithus nascens. The upper part of the Vincentown falls within the upper part of Zone NP 9 and therefore is late Paleocene (Selandian) in age.
Lithology: sand; clay or mud; silt
Woodbury Formation (Upper Cretaceous, lower Campanian) at surface, covers 1 % of this area
Woodbury Formation - Clay-silt, dark-gray; weathers brown and orange pink. Iron oxides fill fractures or form layers in the most weathered beds. Unit is massive except at the base where thin quartz sand layers occur. Locally, thin stringers of pale-greenish-brown, smooth-surface glauconite occur near the top. Unit conspicuously micaceous throughout and contains finely dispersed pyrite, carbonaceous matter, and small pieces of carbonized wood as much as 30 cm (12 in) in length. Small siderite concretions are abundant in the Woodbury in the northern part of the outcrop belt. Unit forms a broad belt in the central sheet from Sandy Hook Bay, southwest to area around East Greenwich, Gloucester County, where it pinches out or changes facies. The Woodbury maintains a thickness of about 15 m (49 ft) throughout most of its outcrop belt. Fossil imprints are abundant. An extensive Woodbury macrofauna was described by Weller (1907) from siderite concretions from a tributary to the Cooper River in the Camden quadrangle. This assemblage is unusual in that it is the only existing outcrop of the Woodbury where calcareous and aragonitic shells are still intact. Most fossils are small, fragmented, and concentrated in small pockets, but larger intact calcareous fossils are scattered throughout the Woodbury. Weller (1907) recorded 57 species from this locality. In addition, this is the same locality that contains fossils of the dinosaur Hadrosaurus foulkii. Pollen collected from the Woodbury was assigned to the CA3 Zone by Wolfe (1976). Biostratigraphic data suggest that the Woodbury is of early Campanian age.
Lithology: clay or mud; silt; sand
Hornerstown Formation (lower Paleocene, Danian) at surface, covers 0.8 % of this area
Hornerstown Formation - Sand, glauconite, clayey, extensively bioturbated, massive, medium-green in the shallow subsurface. Common to abundant microfauna in the subsurface are not present in outcrop. In the deep subsurface, the Hornerstown Formation consists of glauconite sand at base, overlain by a thin, laminated, dark-gray clay-silt that grades upward into a finegrained, clayey glauconite quartz sand. The formation is very thin and rarely exceeds 7.5 m (25 ft) in thickness. The basal contact with the underlying Kc4 cycle is difficult to place because both units are glauconitic sand; however, the basal Hornerstown contains dark-brown phosphatic debris. Less commonly the contact is marked by extensive burrows filled with glauconite sand that project downward into the underlying unit. Gamma logs from the Hornerstown have a very large gamma kick at the base of the formation. The age of the Hornerstown is early Paleocene (Danian) based on the presence of calcareous nannofossils (Chiasmolithus consuetus and Ellipsolithus macellus) and foraminifera characteristic of zones NP 3 and NP 4, and P1a to P1c (Chengjie Liu, Rutgers University, written commun., 1993), respectively.
Lithology: sand; clay or mud
Lower Member of the Kirkwood Formation (lower Miocene, Aquitanian) at surface, covers 6 % of this area
Lower Member - Complex unit in which facies changes are common. In outcrop, some of the lower member is a light-colored quartz sand (Grenloch facies of Isphording, 1970). The facies pinches out rapidly in the subsurface, and the unit is primarily a massive to finely laminated, dark-gray clay (Alloway clay of Kummel and Knapp, 1904). This clay facies occurs as far south as Clayton, Gloucester County, where the lower part changes to a fossiliferous clayey silt. The lower clayey facies thickens to over 30 m (98 ft) in the coastal region. Here, the lower facies is mostly dark-gray clayey silt that is locally very fossiliferous. The unit varies in thickness but is thickest, as much as 80 m (262 ft), in the southeastern part of the central sheet. South of Bridgeton, Cumberland County, sand is present at the top of the member. This sand thickens to over 23 m (75 ft) at the coast where it is part of the "800 foot" sand, the principal aquifer in the coastal region. Quartz and siliceous rock fragments are the major sand minerals. Feldspars typically constitute less than 10 percent of the sand fraction except in the reworked beds where they make up as much as 25 percent of the sand. Mica and wood fragments are minor constituents. The basal contact with the underlying unit is sharp and unconformable. Commonly there is a 0.3- to 1-m (1- to 3-ft)-thick zone along this contact in which coarse-grained quartz sand and some gravel are present. Because of the quartz sand in the lower member in outcrop, some considered the lower member and the Cohansey Formation to be transitional (Isphording, 1970). Obviously this is not the case as there are three other members (Shiloh Marl, Wildwood, and Belleplain) lying between the lower member and the Cohansey. The age of the lower member was determined from planktic foraminifera and diatoms, and from strontium-isotope age estimates. The foraminiferal assemblage includes Globigerina praebulloides, Globigerinoides trilobus, G. altiapertura, and Globorotalia siakensis. These species are characteristic of the lower Miocene Zone 5 of Blow (1969) of Burdigalian age. The diatom assemblage is characterized by Actinoptychus heliopelta, Aulacodiscus rogersii, Coscinodiscus lewisianus, Sceptroneis caduceus, and Triceratium acutum. These diatoms are characteristic of ECDZ 1 of Andrews (1988), which is considered to be early Miocene (Burdigalian) in age. The strontium-isotope analyses of shells from this member indicate ages from 23 to 20.2 Ma (Aquitanian), thereby extending the age of this member (Sugarman and others, 1993). The pollen in the clay facies of the Kirkwood, as determined from the ACGS-4 drillhole, are oak, hickory, and pine with smaller amounts of beech, black gum, sweet gum, alder, elm, linden, and birch. The sandy facies has essentially the same assemblage but has unusually high concentrations of beech. Exotic species such as Podocarpus and Momipites are common in the unit. The cool floral elements found in the overlying Belleplain and Wildwood Members were not found in the lower member.
Lithology: clay or mud; silt; sand
Passaic Formation (Lower Jurassic and Upper Triassic) at surface, covers 6 % of this area
Passaic Formation - Predominantly red beds consisting of argillaceous siltstone; silty mudstone; argillaceous, very fine grained sandstone; and shale; mostly reddish-brown to brownish-purple, and grayish-red. Red beds occur typically in 3- to 7-m (10- to 23-ft-)-thick, cyclic playa-lake-mudflat sequences and fining-upward fluvial sequences. Lamination is commonly indistinct due to burrowing, desiccation, and paleosol formation. Where layering is preserved, most bedforms are wavy parallel lamination and trough and climbing-ripple cross lamination. Calcite- or dolomite-filled vugs and flattened cavities, mostly 0.5 to 0.2 mm (0.02-0.08 in) across, occur mostly in the lower half. Sand-filled burrows, 2 to 5 mm (0.08-0.2 in) in diameter, are prevalent in the upper two-thirds of the unit. Desiccation cracks, intraformational breccias, and curled silt laminae are abundant in the lower half. Lake cycles, mostly 2 to 5 m (7-16 ft) thick, have a basal, greenish-gray, argillaceous siltstone; a medial, dark-gray to black, pyritic, carbonaceous, fossiliferous, and, in places, calcareous lake-bottom fissile mudstone or siltstone; and an upper thick-bedded, gray to reddish and purplish-gray argillaceous siltstone with desiccation cracks, intraformational breccias, burrows, and mineralized vugs. Thickness of the formation between Sourland Mountain and Sand Brook syncline is about 3,500 m (11,483 ft).
Lithology: siltstone; sandstone; shale
Palisade Diabase (Early Jurassic) at surface, covers < 0.1 % of this area
Palisade Diabase
Lithology: diabase
Lockatong Formation (Upper Triassic) at surface, covers 1 % of this area
Lockatong Formation - Predominantly cyclic lacustrine sequences of silty, dolomitic or analcime-bearing argillite; laminated mudstone; silty to calcareous, argillaceous very fine grained sandstone and pyritic siltstone; and minor silty limestone, mostly light- to dark-gray, greenishgray, and black. Grayish-red, grayish-purple, and dark-brownish-red sequences (Trlr) occur in some places, especially in upper half. Two types of cycles are recognized: freshwater-lake (detrital) and alkaline-lake (chemical) cycles. Freshwater-lake cycles average 5.2 m (17 ft) thick. They consist of basal, transgressive, fluvial to lake-margin deposits that are argillaceous, very fine grained sandstone to coarse siltstone with indistinct lamination, planar or cross lamination, or are disrupted by convolute bedding, desiccation cracks, root casts, soil-ped casts, and tubes. Medial lake-bottom deposits are laminated siltstones, silty mudstones, or silty limestones that are dark gray to black with calcite laminae and grains and lenses, or streaks of pyrite; fossils are common, including fish scales and articulated fish, conchostracans, plants, spores, and pollen. Upper regressive lake margin, playa lake, and mudflat deposits are light- to dark-gray silty mudstone to argillitic siltstone or very fine grained sandstone, mostly thick bedded to massive, with desiccation cracks, intraformational breccias, faint wavy laminations, burrows, euhedral pyrite grains, and dolomite or calcite specks. Alkaline-lake cycles are similar to freshwater-lake cycles, but are thinner, averaging 3 m (10 ft), have fewer fossils (mainly conchostracans), and commonly have red beds, extensive desiccation features, and abundant analcime and dolomite specks in the upper parts of cycles. Thickness near Byram is about 1,070 m (3,510 ft). The formation thins to the southeast and northeast; thickness near Princeton is less than 700 m (2,297 ft).
Lithology: argillite; mudstone; sandstone; siltstone; limestone
Passaic Formation gray bed (Lower Jurassic and Upper Triassic) at surface, covers 0.4 % of this area
Passaic Formation gray bed - Upper Triassic gray lake deposits (Trpg) consist of gray to black silty mudstone, gray and greenish- to purplish-gray argillaceous siltstone, black shale, and medium- to dark-gray, argillaceous, fine-grained sandstone and are abundant in the lower half of the Passaic Formation. Gray lakebeds occur in groups of two to five cycles although they also occur as single cycles in some parts of the formation. Several lakebed sequences consisting of one or two thick groups of drab-colored beds as much as 30 m (98 ft) thick or more can be traced over tens of kilometers. Many gray-bed sequences are locally correlated within fault blocks; some can be correlated across major faults or intrusive rock units. Thickness of the (entire Passaic) formation between Sourland Mountain and Sand Brook syncline is about 3,500 m (11,483 ft).
Lithology: fine-grained mixed clastic; siltstone; black shale; sandstone
Orange Mountain Basalt (Lower Jurassic) at surface, covers 0.6 % of this area
Orange Mountain Basalt - Basalt, fine-grained to aphanitic, dark-greenish-gray, composed mostly of calcic plagioclase and augite; crystals smaller than 1 mm (0.04 in). Unit consists of three major tholeiitic lava-flow sequences, each about 80 m (262 ft) thick. Lowest flow is generally massive with widely spaced curvilinear joints; middle flow is massive or has columnar joints; lower part of uppermost flow has pillow structures and upper part has pahoehoe flow structures. Thickness in map area is about 160 m (525 ft).
Lithology: basalt
Hook Mt. Basalt (Lower Jurassic) at surface, covers 0.4 % of this area
Hook Mt. Basalt (Olsen, 1980) - Light- to dark-greenish-gray, medium- to coarse-grained, amygdaloidal basalt composed of plagioclase (typically An65 and commonly porphyritic), clinopyroxene (augite and pigeonite), and iron-titanium oxides such as magnetite and ilmenite. Locally contains small spherical to tubular cavities (gas-escape vesicles), some filled by zeolite minerals or calcite. Consists of two major flows. Base of lowest flow is intensely vesicular. Tops of flows are weathered and vesicular. Maximum thickness is about 110 m (360 ft) (Olsen and others, 1989).
Lithology: basalt
Amphibolite (Middle Proterozoic) at surface, covers < 0.1 % of this area
Amphibolite - commonly biotitic; garnetiferous, pyroxenic, in and adjacent to Adirondack Highlands.
Lithology: amphibolite
Trenton Gravel (Quaternary) at surface, covers < 0.1 % of this area
Trenton Gravel - Gray or pale-reddish-brown, very gravelly sand interstratified with crossbedded sand and clay-silt beds; includes areas of Holocene alluvium and swamp deposits.
Lithology: sand; clay or mud; silt; gravel; alluvium
Microantiperthite Alaskite (Middle Proterozoic) at surface, covers < 0.1 % of this area
Microantiperthite Alaskite - White-weathering, locally rusty, light-greenish-gray medium- to coarse-grained, gneissic granite and alaskite containing microantiperthite, quartz, oligoclase, and sparse amounts of hornblende, clinopyroxene, biotite, and magnetite.
Lithology: granite
Microperthite Alaskite (Middle Proterozoic) at surface, covers 0.4 % of this area
Microperthite Alaskite - Pink- to buff-weathering, light-pinkish-gray or pinkish-white, medium- to coarse-grained, gneissoid to indistinctly foliated granite composed principally of microcline microperthite, quartz and oligoclase. Includes small bodies of amphibolite not shown on map.
Lithology: granite; amphibolite
Hornblende-Quartz-Feldspar Gneiss (Middle Proterozoic) at surface, covers 0.1 % of this area
Hornblende-Quartz-Feldspar Gneiss - Pinkish-gray- to buff-weathering, light- pinkish-white to pinkish-gray, fine- to medium-grained, massive to moderately well layered gneiss containing microcline, quartz, oligoclase, hornblende, and magnetite. Locally contains garnet and biotite.
Lithology: paragneiss
Bossardville Limestone (Upper Silurian) at surface, covers < 0.1 % of this area
Bossardville Limestone (White, 1882) - Light-gray to yellowish- gray-weathering, medium-gray to medium-dark-gray, very fine grained, locally fossiliferous, laminated to thin-bedded limestone and argillaceous limestone. Desiccation polygons occur in southwest. Lower contact is gradational and placed at top of uppermost dolomite. Thickness approximately 30 m (100 ft) in southwest, thinning to 3.1 m (10 ft) at New Jersey-New York State boundary.
Lithology: limestone
Boonton Formation (Lower Jurassic) at surface, covers 1 % of this area
Boonton Formation (Olsen, 1980) - Reddish-brown to brownish-purple, fine-grained sandstone, siltstone, and mudstone; sandstone commonly micaceous, interbedded with siltstone and mudstone in fining-upward sequences mostly 1.5 to 4 m (5-13 ft) thick. Red, gray and brownish-purple siltstone and black, blocky, partly dolomitic siltstone and shale common in lower part. Irregular mudcracks, symmetrical ripple marks, and burrows, as well as gypsum, glauberite, and halite pseudomorphs are abundant in red mudstone and siltstone. Gray, fine-grained sandstone may have carbonized plant remains and reptile footprints in middle and upper parts of unit. Near Morristown, beds of quartz-pebble conglomerate (unit Jbcq) as much as 0.5 m (1.6 ft) thick interfinger with beds of sandstone, siltstone, and shale. Northeast of Boonton, beds of quartz-pebble conglomerate (not mapped separately as Jbcq) occur locally with conglomerate containing abundant clasts of gneiss and granite in matrix of reddish-brown sandstone and siltstone. Maximum thickness is about 500 m (1,640 ft).
Lithology: sandstone; siltstone; mudstone; shale; conglomerate; evaporite
Passaic Formation Limestone-clast Conglomerate facies (Lower Jurassic and Upper Triassic) at surface, covers < 0.1 % of this area
Passaic Formation Limestone-clast Conglomerate facies - Limestone conglomerate unit (JTrpcl) is medium-bedded to massive, pebble to boulder conglomerate. Clasts are subangular dolomitic limestone in matrix of brownish- to purplish-red sandstone to mudstone; matrix weathers light-gray to white near faults. Maximum thickness unknown.
Lithology: conglomerate; limestone; sandstone; mudstone
Biotite-quartz-oligoclase gneiss (Middle Proterozoic) at surface, covers 0.4 % of this area
Biotite-quartz-oligoclase gneiss - White- to light-gray-weathering, light- to medium-gray or greenish-gray, fine- to coarse-grained, massive to moderately well layered, foliated gneiss composed of oligoclase or andesine, quartz, biotite, and, locally, garnet. Commonly interlayered with amphibolite.
Lithology: gneiss; amphibolite
Beekmantown Group, Upper Part (Lower Ordovician) at surface, covers 0.3 % of this area
Beekmantown Group, Upper Part (Clarke and Schuchert, 1899) - Locally preserved upper beds are light- to medium-gray- to yellowish-gray-weathering, medium-light- to medium-gray, aphanitic to medium-grained, thin- to thick-bedded, locally laminated, slightly fetid dolomite. Medium-dark to dark-gray, fine-grained, medium-bedded, sparsely fossiliferous limestone lenses occur locally. Lower beds are medium-dark- to dark-gray, medium- to coarse-grained, mottled surface weathering, medium- to thick-bedded, strongly fetid dolomite that contains pods and lenses of dark-gray to black chert. Cauliflower-textured black chert beds of variable thickness occur locally. Gradational lower contact is placed at top of laminated to thin-bedded dolomite of the lower part (Obl) of the Beekmantown Group. Contains conodonts high in the Rossodus manitouensis zone to low zone D of the North American midcontinent province as used by Sweet and Bergstrom (1986). Upper beds are included in Epler Formation; lower beds are included in Rickenbach Dolomite of Drake and Lyttle (1985) and Drake and others (1985); entire upper part (Obu) is Ontelaunee Formation of Markewicz and Dalton (1977). Thickness ranges from 0 to 244 m (0-800 ft).
Lithology: dolostone (dolomite); limestone
Cohansey Formation (Middle Miocene, Serravallian) at surface, covers 31 % of this area
Cohansey Formation - Sand, fine- to coarse-grained, locally gravelly, massive to crossbedded, gray-brown or dark-gray; weathers yellow to white. Typically, the weathered sand is nearly all quartz or rock fragments of orthoquartzite. Where less weathered, small amounts (5-10 percent) of potassium feldspar are present. Interbedded with discrete beds of clay or silty clay, thin- to thick-bedded, massive to finely laminated, dark-gray; weathers white, yellow, or red. Darkgray beds commonly contain carbonized wood fragments, some of which are log size. The thicker clay beds occur in lenses that commonly have small to very large pieces of lignitized wood. An extensive, well-preserved leaf flora was collected from a very thick clay lens in the Cohansey near Millville, Cumberland County. The leaf flora were dominated by Alangium sp., a tree no longer growing in eastern North America (J.A. Wolfe, written commun., 1992). Locally, formation consists of several thin- to thickbedded, upward-coarsening sections (clay to sand). The depth of weathering ranges from 24 m (79 ft) in the ACGS-4 corehole near Mays Landing, Atlantic County (Owens and others, 1988), to 70 m (230 ft) in the Atlantic City corehole (F-F'). In the southern part of the southern sheet, in the Belleplain State Forest, Cape May County (G-G'), the formation consists of thin to thick beds of fine- to medium-grained, micaceous quartz (both colorless and green) sand and dark-gray to grayish-brown, woody clay. The sand is locally coarsely stratified (typically small-amplitude crossbeds) and locally highly bioturbated. The clay is extensively bioturbated. These beds represent the deepest marine beds found in the Cohansey in the New Jersey Coastal Plain. The basal contact with underlying units has considerable relief. The contact is sharp and commonly consists of a thin bed of fine gravelly sand. The original thickness of the Cohansey is difficult to ascertain because of extensive erosion. The formation lies in a broad channel and is thickest in the thalweg near Atlantic City where it is nearly 107 m (351 ft) thick. The base of the formation rises rapidly to the south and north of this channel axis. In downdip areas near Belleplain State Forest, the Cohansey contains marginal marine and shelfal facies. The shelfal facies is composed of interbedded, highly bioturbated, micaceous, slightly glauconitic quartz sand and massive clay. Most of the sand in the Cohansey is medium grained and moderately sorted although coarse and fine sandy beds also are common. Beds that have gravel as a major component are locally common in the mixed marine-nonmarine facies in the northeastern corner of the southern sheet. Here, the gravel occurs in well-defined channels. Most of the gravel is 2.5 cm (1 in) or less in diameter, although clasts up to 13 cm (5 in) in diameter have been locally observed. The gravel is mostly quartz or quartzite with lesser amounts of white and black chert. Previously, the age of the Cohansey was postulated from its stratigraphic position, its perceived contact relations with the underlying Kirkwood Formation (conformable or unconformable), and its macro- and microflora. The palynology of upper Tertiary formations in the northeastern United States is, however, only generally understood. Commonly, Pliocene beds have less exotic species than Oligocene or Miocene beds. If this is the case, then the Cohansey, which has a large number of exotics of some species, has more Miocene affinities than Pliocene, an age some have assigned to this formation. Ager (in Owens and others, 1988) discusses the microflora in the Cohansey near Mays Landing. He notes that the Cohansey has a large number of exotics similar to those in the underlying Wildwood Member of the Kirkwood, and because of this, thought the Cohansey to be Miocene. Pollen from the Cohansey at Belleplain also has a large variety of exotics in a warm temperate to subtropical pollen assemblage (Les Sirkin, Adelphi University, oral commun., 1991), which includes Clethra, Cyathea, Cyrilla, Engelhardia, Epilobium, Gordonia, Planera, Podocarpus, Pterocarya, and Symplocos. The major sources of tree pollen at Belleplain are pine, oak, and hickory. The contained dinocyst flora from marine beds at Belleplain can be correlated with the known dinocyst assemblages from the Choptank and the lower part of the St. Marys Formation of the Chesapeake Bay region and therefore is middle Miocene in age (Laurent de Verteuil, University of Toronto, written commun., 1991). These dinoflagellate data therefore confirm the Miocene rather than Pliocene age for the Cohansey. The strontium-isotope age from shells at the base of the Cohansey in an offshore well (ACOW-1) was approximately 11 Ma or latest middle Miocene or late Serravallian
Lithology: alluvium
Lockatong Formation Arkosic Sandstone facies (Upper Triassic) at surface, covers 0.2 % of this area
Lockatong Formation Arkosic Sandstone facies - Cycles in northern Newark basin are thinner and have arkosic sandstone in lower and upper parts. Upper part of formation in northern basin composed mostly of light-gray to light-pinkish-gray or light-brown, coarse- to fine-grained, thick- to massive-bedded arkosic sandstone (Trla). Thermally metamorphosed into hornfels where intruded by diabase (Jd).
Lithology: arkose; hornfels
Jacksonburg Limestone (Middle Ordovician) at surface, covers 0.2 % of this area
Jacksonburg Limestone (Kummel, 1908; Miller, 1937) - Upper part is medium- to dark-gray, laminated to thin-bedded shaly limestone and less abundant medium-gray arenaceous limestone containing quartz-sand lenses. Upper part thin to absent to northeast. Lower part is interbedded medium- to dark-gray, fine- to medium-grained, very thin to medium-bedded fossiliferous limestone and minor medium- to thick-bedded dolomite-cobble conglomerate having a limestone matrix. Unconformable on Beekmantown Group and conformable on the discontinuous sequence at Wantage in the Paulins Kill area. Contains conodonts of North American midcontinent province from Phragmodus undatus to Aphelognathus shatzeri zones of Sweet and Bergstrom (1986). Thickness ranges from 41 to 244m (135-800 ft).
Lithology: limestone; conglomerate
Hornblende Syenite (Middle Proterozoic) at surface, covers 0.2 % of this area
Hornblende Syenite - Tan- to buff-weathering, pinkish-gray or greenish-gray, medium- to coarse-grained, gneissoid syenite and lesser amounts of quartz syenite containing microcline microperthite, oligoclase, quartz, and hornblende. Some phases are monzonite or monzodiorite.
Lithology: syenite; quartz syenite; monzonite; monzodiorite
Marshalltown Formation (Upper Cretaceous, upper and middle Campanian) at surface, covers 0.4 % of this area
Marshalltown Formation - Sand, quartz and glauconite, fine- to medium-grained, silty and clayey, massive, dark-gray; weathers light brown or pale red, extensively bioturbated. Very glauconitic in basal few meters; glauconite concentration decreases upward so that in upper part of unit, quartz and glauconite are nearly equal. Feldspar, mica, pyrite, and phosphatic fragments are minor sand constituents. Locally, very micaceous (mostly green chlorite) with sparse carbonized wood fragments. Fine-grained pyrite abundant throughout formation. Local thin, pebbly zones with large fossil impressions occur in the middle of the formation. In the upper part of the formation, quartz increases to about 40 percent. Unit crops out in a narrow belt throughout the map area and forms isolated outliers in the central sheet. Best exposures are along Crosswicks Creek in the Allentown quadrangle. In the southern sheet, the Marshalltown underlies a narrow belt in the uplands and broadens to the southwest. Many Marshalltown exposures occur along Oldmans Creek and its tributaries near Auburn, Gloucester County. The contact with the underlying Englishtown Formation is sharp and unconformable. The basal few centimeters of the Marshalltown contain siderite concentrations, clay balls, and wood fragments reworked from the underlying Englishtown. Many burrows, some filled with glauconite, project downward into the Englishtown for about one meter (3 ft) giving a spotted appearance to the upper part of the Englishtown (Owens and others, 1970). The Marshalltown is the basal transgressive unit of a sedimentation cycle that includes the regressive deposits of the overlying Wenonah and Mount Laurel Formations resembling the overlying Red Bank Formation to Navesink Formation cycle in its asymmetry. Within the map area, only a few long-ranging megafossils occur in the Moorestown quadrangle (Richards, 1967). To the south, in the type area, Weller (1907) reported diverse molluskan assemblages indicating a Campanian age. More importantly, Olsson (1964) reported the late Campanian foraminifera Globotruncana calcarata Cushman from the upper part of the formation. No G. calcarata were found during our investigations. Wolfe (1976) assigned the pollen assemblage of the Marshalltown to the CA5A Zone considered to be Campanian. The Marshalltown has most recently been assigned to Zone CC 20-21 (Sugarman and others, 1995) of middle and late Campanian age (Perch-Nielsen, 1985).
Lithology: sand; clay or mud; silt
Tinton Formation (Upper Cretaceous, upper Maastrichtian) at surface, covers 0.4 % of this area
Tinton Formation - Sand, quartz and glauconite, sideritecemented, indurated, reddish-brown to dark-gray. The Tinton was extensively dissected prior to deposition of the overlying Hornerstown Formation. Unit can be traced in the subsurface only as far downdip (south) as the Freehold area, Monmouth County. The Tinton in the Freehold core is about 6 m (20 ft) thick and thickens to the east where at Rumson, Monmouth County, it is 12 m (40 ft) thick. The Tinton unconformably overlies the Kc4 cycle. The Tinton is more quartzose to the west and more glauconitic to the east. The unit represents an incomplete cycle of sedimentation as it consists only of subtidal marine beds and lacks nearshore sands. Siderite cement, which imparts the hardness to the Tinton, is irregularly distributed throughout the unit. Because of its extensive induration, sand and clay mineralogy was not determined. Gamma logs of the Tinton, because of the widespread presence of siderite cement in the matrix, have a relatively high intensity and are similar in shape to gamma logs for clayey units. No fossils were found in subsurface samples of this formation, but fossils from outcrops indicate a late Maastrichtian age.
Lithology: sand
Hornblende granite and granite gneiss (Middle Proterozoic) at surface, covers < 0.1 % of this area
Hornblende granite and granite gneiss - with subordinate leucogranite.
Lithology: granite; granitic gneiss
Chestnut Hill Formation (Late Proterozoic) at surface, covers < 0.1 % of this area
Chestnut Hill Formation (Drake, 1984) - Interbedded arkose, ferruginous quartzite, quartzite conglomerate, metarhyolite, and metasaprolite. Confined to a few small areas north and east of Phillipsburg, on the western side of Bowling Green Mountain, northwest of High Bridge, and a few areas too small to show at this map scale.
Lithology: arkose; quartzite; conglomerate; meta-rhyolite
Pyroxene Granite (Middle Proterozoic) at surface, covers 0.8 % of this area
Pyroxene Granite - Gray- to buff- or white-weathering, greenish-gray, medium- to coarse-grained, massive, gneissoid to indistinctly foliated granite containing mesoperthite to microantiperthite, quartz, oligoclase, and clinopyroxene. Common accessory minerals include titanite, magnetite, apatite, and trace amounts of pyrite. Some phases are monzonite, quartz monzodiorite, or granodiorite. Locally includes small bodies of amphibolite not shown on map.
Lithology: granite; monzonite; quartz monzodiorite; granodiorite; amphibolite
Pyroxene Alaskite (Middle Proterozoic) at surface, covers < 0.1 % of this area
Pyroxene Alaskite - Light-gray- or tan-weathering, greenish-buff to light-pinkish-gray, medium- to coarse-grained, massive, moderately foliated granite composed of mesoperthite to microantiperthite, oligoclase, and quartz. Common accessory minerals are clinopyroxene, titanite and magnetite. Locally includes small bodies of amphibolite not shown on map.
Lithology: granite; amphibolite
Basalt-clast Conglomerate (Lower Jurassic) at surface, covers < 0.1 % of this area
Basalt-clast Conglomerate - Dark to very-dark-gray conglomerate with clasts mostly of sub-angular to subrounded greenish-black basalt cobbles and boulders. Other clasts (about 10 to 15%) are pebbles to boulders of hornblende granite with pink feldspar. Matrix is dark-pinkish-gray arkosic sand. Locally onlaps the Hook Mountain Basalt along the Ramapo Fault in northeast part of map area. Maximum thickness of unit unknown.
Lithology: conglomerate; arkose
Merchantville Formation (Upper Cretaceous, lower Campanian) at surface, covers 1 % of this area
Merchantville Formation - Sand, glauconite, locally has high quartz content, very clayey and silty, massive to thick-bedded, grayish-olive-green to dark-greenish-gray; weathers moderate brown or moderate yellow brown. Mica, feldspar, and pyrite are minor sand constituents. Very micaceous at base. Locally, has extensive iron incrustations in near-surface weathered beds. Fossil molds are mostly phosphatic. Fossils typically occur in siderite concretions. No calcareous fossils were found in outcrop. The Merchantville forms a continuous narrow to wide belt throughout the map area. The unit is about 6 m (20 ft) thick in the northern part of the central sheet, about 20 m (66 ft) thick in the Trenton area, and 12 to 15 m (39-49 ft) thick throughout the southern sheet. The formation is best exposed in the Trenton East quadrangle, mainly in the tributaries on the western side of Blacks Creek and south of Bordentown, Burlington County, where the entire thickness of the formation can be seen in gullies (Owens and Minard, 1964b). The basal contact with the underlying Magothy or Cheesequake Formations is sharp and disconformable. At most places, a reworked zone about 0.3 to 1 m (1-3 ft) thick is present at the base. This basal bed contains reworked lignitized wood, siderite concretions as much as 13 cm (5 in) in diameter, scattered pebbles and coarse-grained quartz sand and is burrowed. Most burrows project downward into the underlying formations. The Merchantville is the basal bed of a lower Campanian transgressive-regressive cycle that includes the overlying Woodbury and Englishtown Formations. Merchantville faunas were analyzed by Sohl (in Owens and others, 1977) who concluded that northern fauna represented deposition on a lower shoreface or in the transition to an inner shelf, whereas the southern fauna was a deeper water assemblage, probably inner shelf. Macrofossils occur as internal and external molds and include the ammonites Menabites (Delawarella) delawarensis and Scaphites (Scaphites) hippocrepis III. The Scaphites is of the type III variety of Cobban (1969) and is indicative of the lower, but not the lowest, Campanian. More recently, Kennedy and Cobban (1993), detailing the ammonite assemblage that includes Baculites haresi, Chesapeakella nodatum, Cryptotexanites paedomorphicus sp., Glyptoxoceras sp., Menabites (Delawarella) delawarensis, M. (Delawarella) vanuxemi, Menabites (Bererella) sp., Pachydiscus (Pachydiscus) sp., Placenticeras placenta, Pseudoscholenbachia cf. P. chispaensis, Scaphites (Scaphites) hippocrepis III, Submortoniceras punctatum, S. uddeni, and Texanites (Texanites) sp., concluded that the Merchantville is of late early Campanian age. Wolfe (1976) indicated that the Merchantville microflora was distinct from overlying and underlying units and designated it Zone CA2 of early Campanian age.
Lithology: sand; clay or mud; silt
Sandy Hook Member of the Red Bank Formation (Upper Cretaceous, upper and middle Maastrichtian) at surface, covers 0.3 % of this area
Sandy Hook Member - Sand, quartz, fine-grained, clayey, very micaceous, massive, dark-gray, fossiliferous. Feldspar, muscovite, chlorite, and biotite are minor sand constituents. Well exposed at Poricy Brook in the Long Branch quadrangle. The Sandy Hook is much thinner than the overlying Shrewsbury Member and is a maximum of 10 m (33 ft) thick.
Lithology: sand; clay or mud
Franklin Marble (Middle Proterozoic) at surface, covers 0.2 % of this area
Franklin Marble - White- to light-gray-weathering, white, grayish-white, or, less commonly pinkish-orange, coarse- to locally fine-crystalline calcite marble with accessory amounts of graphite, phlogopite, chondrodite, clinopyroxene, and serpentine. Contains pods and layers of clinopyroxene-garnet skarn, hornblende skarn, and clinopyroxene-rich rock. Thin layers of metaquartzite occur locally. Intruded by the Mount Eve Granite in the Pochuck Mountain area. Franklin Marble is host to the Franklin and Sterling Hill zinc ore bodies; exploited for talc and asbestiform minerals near Easton, Pennsylvania. Subdivided into an upper marble, "Wildcat marble," and a lower marble, "Franklin marble," by New Jersey Zinc Co. geologists (Hague and others, 1956).
Lithology: marble; skarn (tactite); quartzite
Oriskany Group, undivided (Lower Devonian) at surface, covers < 0.1 % of this area
Oriskany Group, undivided (Willard, 1938) - Thickness ranges from 38 m (125 ft) in southwest to 52 m (170 ft) in northeast. Ridgely Sandstone (Swartz and others, 1913) - White-weathering, medium-gray, medium- to thick-bedded, carbonate-cemented quartz-pebble conglomerate and coarse quartz sandstone, which contain abundant brachiopods. Moderately well sorted, subrounded sand gains. Unit thins northeastward and pinches out at Peters Valley. Lower contact abrupt. Thickness ranges from 0 to 10 m (0-32 ft). Shriver Chert (Swartz and others, 1913) - Medium- to dark-gray-weathering, black to dark-gray, medium-to-thick-bedded siltstone and shale containing interbedded black chert and local chert-bearing limestone. Present only in southwestern part of outcrop area where lower contact is gradational with silty limestone of Glenarie Formation. Thickness ranges from 0 to 9 m (0-30 ft). Glenarie Formation (Chadwick, 1908) - Medium-gray-weathering, medium- to dark-gray, fine-grained, thin- to medium-bedded, fossiliferous, silty limestone, and local chert lenses. Unit thickens to northeast. Lower contact probably gradational. Thickness ranges from 17 to 52 m (55-170 ft).
Lithology: sandstone; limestone; siltstone; conglomerate; black shale; chert
Microcline Gneiss (Middle Proterozoic) at surface, covers 0.3 % of this area
Microcline Gneiss - Light-gray- to pinkish-white-weathering, tan to pinkish-white, fine- to medium-grained, well-layered gneiss composed principally of quartz, microcline, and lesser amounts of oligoclase. Common accessory minerals include biotite, garnet, magnetite, and, locally, sillimanite.
Lithology: paragneiss
Cheesequake Formation (Upper Cretaceous, lower Campanian and upper Santonian) at surface, covers < 0.1 % of this area
Cheesequake Formation - New unit named herein for outcrops in gullies at Cheesequake in the eastern part of the South Amboy 7.5-min quadrangle. Basal sand, quartz and glauconite, fine-grained, clayey, thin-bedded, dark-greenish-gray; middle part, quartz sand, very fine grained, thick-bedded, dark-gray, micaceous, and clayey silt with scattered and varying amounts of glauconite sand; upper part, quartz sand, fine-grained, clayey, thinbedded. Sand, excluding glauconite sand beds, is primarily quartz with small amounts of feldspar and mica. In most areas, particularly in the updip sections, the upper sand has been eroded away. This formation underlies most of the map area and is as much as 43 m (141 ft) thick. Nannofossils obtained from the Toms River and Freehold drillholes indicate that the Cheesequake Formation is latest Santonian at the base to earliest Campanian at the top (P.C. Valentine, oral commun., 1989) or equivalent to Zones CC16 to CC17. Thus the Santonian-Campanian boundary lies within the Cheesequake Formation. Studies of pollen (Litwin and others, 1993) in outcrop indicate a pollen assemblage containing elements of the ?Pseudoplicapollis cuneata-Semioculopollis verrucosa Zone (Vc of Christopher, 1982) and the CA2 Zone of Wolfe (1976).
Lithology: sand; clay or mud; silt
Hardyston Quartzite (Lower Cambrian) at surface, covers 0.1 % of this area
Hardyston Quartzite (Lower Cambrian) (Wolff and Brooks, 1898) - Light- to medium-gray and bluish-gray conglomeratic sandstone. Varies from pebble conglomerate, to fine-grained, well-cemented quartzite, to arkosic or dolomitic sandstone. Conglomerate contains subangular to subrounded white quartz pebbles up to 2.5 cm (1 in.). Lower contact unconformable. About 0 to 9 m (1-30 ft) thick.
Lithology: quartzite; conglomerate; sandstone
Allentown Dolomite (Lower Ordovician and Upper Cambrian) (Wherry, 1909) (Lower Ordovician and Upper Cambrian) at surface, covers 2 % of this area
Allentown Dolomite (Lowest Lower Ordovician and Upper Cambrian) (Wherry, 1909) - Medium- to very light gray, fine- to medium-grained, very thin to very thick bedded dolomite containing minor orthoquartzite and shale. Oolites and algal stromatolites occur throughout unit. Shaly dolomite increases downward towards lower conformable contact with the Leithsville Formation. Unit does not crop out but is known from subsurface borings near Flanders (Volkert and others, 1990). Thickness ranges from 0 to 73 m (0-240 ft) due to erosion.
Lithology: dolostone (dolomite); orthoquartzite; shale
Martinsburg Formation (Ordovician) at surface, covers < 0.1 % of this area
Martinsburg Formation - Gray to dark-gray, buff-weathering shale.
Lithology: shale
Brunswick Formation (Upper Triassic) at surface, covers < 0.1 % of this area
Brunswick Formation - mudstone, sandstone and arkose.
Lithology: mudstone; sandstone; arkose
Hypersthene-Quartz-Oligoclase Gneiss (Middle Proterozoic) at surface, covers 0.4 % of this area
Hypersthene-Quartz-Oligoclase Gneiss - Gray- to tan-weathering, greenish-gray to greenish-brown, medium-grained, moderately well layered and foliated, greasy-lustered gneiss of charnockitic affinity composed of andesine or oligoclase, quartz, clinopyroxene, hornblende, hypersthene, and sparse amounts of biotite. Commonly interlayered with amphibolite and mafic-rich quartz-plagioclase gneiss.
Lithology: gneiss; amphibolite
Ramseyburg Member (Upper and Middle Ordovician) at surface, covers 2 % of this area
Ramseyburg Member (Drake and Epstein, 1967) - Interbedded medium- to dark-gray, to brownish-gray, fine- to medium-grained, thin- to thick-bedded graywacke sandstone and siltstone and medium- to dark-gray, laminated to thin-bedded shale and slate. Unit may form complete turbidite sequences, Tabcde (Bouma, 1962), but basal cutout sequences Tcde dominate. Basal scour, sole marks, and soft-sediment distortion of beds are common in graywacke. Thermally metamorphosed near intrusive bodies. Lower contact placed at bottom of lowest thick- to very thick bedded graywacke, but contact locally grades through sequence of dominantly thin-bedded shale and slate and minor thin- to medium-bedded discontinuous and lenticular graywacke beds in the Bushkill member. Parris and Cruikshank (1992) correlate unit with Orthograptus ruedemanni to lowest part of Climacograptus spiniferus zones of Riva (1969, 1974). Thickness ranges from 640 m (2,100 ft) in Delaware River Valley, to 1,524 m (5,000 ft) near Stillwater, to 1067 m (3,500 ft) at New York State line.
Lithology: graywacke; siltstone; shale; slate
Wenonah Formation (Upper Cretaceous, upper Campanian) at surface, covers 1 % of this area
Wenonah Formation - Sand, quartz and mica, fine-grained, silty and clayey, massive to thick-bedded, dark-gray to medium-gray; weathers light brown to white, extensively bioturbated, very micaceous, locally contains high concentrations of sand-sized lignitized wood and has large burrows of Ophiomorpha nodosa. Feldspar (5-10 percent) is a minor sand constituent. Unit crops out in a narrow belt from Sandy Hook Bay on the central sheet and pinches out southwest of Oldmans Creek, Salem County, on the southern sheet. Isolated outliers of the Wenonah are detached from the main belt in the central sheet area. Thickness is about 10 m (33 ft) in the northern part of the central sheet, 20 m (66 ft) in the southwestern part of the central sheet, and 7.5 m (25 ft) in the southern sheet. The Wenonah is gradational into the underlying Marshalltown Formation. A transition zone of several meters is marked by a decrease in mica and an increase in glauconite sand into the Marshalltown. Fossil casts are abundant in the Wenonah. Weller (1907) reported Flemingostrea subpatulata Hop Brook in the Marlboro quadrangle indicating a late Campanian age. Wolfe (1976) placed the Wenonah microflora in his CA5A assemblage, considered to be of late Campanian age. Kennedy and Cobban (1994) identified ammonites including Baculites cf. B. scotti, Didymoceras n. sp., Menuites portlocki, Nostoceras (Nostoceras) puzosiforme n. sp., Nostoceras (Nostoceras) aff. N. colubriformus, Parasolenoceras sp., Placenticeras placenta, P. minor n. sp., and Trachyscaphites pulcherrimus. The presence of M. portlocki and T. pulcherrimus indicates late, but not latest, Campanian.
Lithology: sand; clay or mud; silt
Shark River Formation (upper and middle Eocene, Priabonian through Lutetian) at surface, covers < 0.1 % of this area
Shark River Formation - Consists of three lithofacies, a basal clayey, greenish-gray glauconite sand; a middle dark-green to gray-green silty clay or clayey silt; and an upper medium-gray to gray-green, silty quartz sand. Updip beds are cyclic with a fine- to medium-grained, somewhat clayey, fossiliferous, dark-green, glauconite-quartz (25 percent) sand at the base. The basal lithofacies is about 12 m (39 ft) thick in the southern sheet and 3 m (10 ft) thick in the central sheet. There is a general increase in quartz sand upward and a change in color to dark gray or brownish gray. Locally, some of the beds are more clayey and have more calcareous shell fragments. The middle clay and silt facies is typically the thickest lithofacies in most Shark River sections (as much as 38 m (125 ft) thick) and is massive to thick bedded. The thick-bedded parts typically consist of intercalated silty and clayey beds that are extensively bioturbated. Macro- and microfossils are abundant in this facies. Most of the macrofossils are thin-walled pelecypods. This facies is gradational into the upper quartz-sand facies. The quartz sand is well developed in the Toms River Chemical Plant drillhole, Toms River, Ocean County (sheet 1). This facies apparently was beveled off in the updip areas during erosion prior to deposition of the Kirkwood Formation. The Shark River Formation in the updip area near Bridgeton, Cumberland County (sheet 2), is about 52 m (171 ft) thick. All of the Shark River lithologies in the downdip area are extensively bioturbated. The Shark River is thickest (more than 60 m (197 ft)) in a trough that lies near the middle of the southern sheet. The contact between the Shark River and the underlying Manasquan Formation is sharp and contains a thin zone of reworked glauconite sand, granules of quartz, and phosphatic debris. On most gamma-ray logs through this contact, there is a sharp gamma high reflecting the concentration of phosphatic sediment. The vertical arrangement of facies in this formation is from a transgressive (mostly clay) facies at the base to a regressive (mostly sand) facies at the top. Calcareous nannofossils and foraminifera were used to date this unit. Where the unit is thickest, the nannofossils range from the upper part of Zone NP 14 (Rhabdosphaera inflata) to the lower part of Zone NP 18 (Chiasmolithus oamaruensis). The entire sequence of Zones NP 14 through NP 18 was observed only in the ACGS-4 corehole near Mays Landing. The planktic foraminifera zones range from the Turborotalia frontosa Zone at the base to the Turborotalia pomeroli/Turborotalia cerroazulensis Zone at the top. A middle to early late Eocene age for the Shark River is indicated by these zones (Poore and Bybell, 1988).
Lithology: silt; clay or mud; sand
Jacksonburg Limestone and Sequence at Wantage, undivided (Middle Ordovician) at surface, covers < 0.1 % of this area
Jacksonburg Limestone and Sequence at Wantage, undivided - Jacksonburg Limestone - Upper part is medium- to dark-gray, laminated to thin-bedded shaly limestone and less abundant medium-gray arenaceous limestone containing quartz-sand lenses. Upper part thin to absent to northeast. Lower part is interbedded medium- to dark-gray, fine- to medium-grained, very thin to medium-bedded fossiliferous limestone and minor medium- to thick-bedded dolomite-cobble conglomerate having a limestone matrix. Unconformable on Beekmantown Group and conformable on the discontinuous sequence at Wantage in the Paulins Kill area. Contains conodonts of North American midcontinent province from Phragmodus undatus to Aphelognathus shatzeri zones of Sweet and Bergstrom (1986). Thickness ranges from 41 to 244m (135-800 ft). Sequence at Wantage - Restricted, discontinuous sequence of interbedded limestone, dolomite, conglomerate, siltstone, and shale. Upper part is medium-yellowish-brown- to olive-gray-weathering, medium- to dark-gray, very fine to fine-grained, laminated to massive limestone and dolomite that grade down into underlying clastic rocks of lower part. Upper part locally absent. Lower part ranges from grayish-red, medium-gray, pale-brown, and greenish-gray to pale-green mudstone and siltstone containing disseminated subangular to subrounded chert-gravel, quartz-sand lenses, and chert-pebble conglomerate. Lower contact unconformable. Thickness ranges from 0 to 46 m (0-150 ft).
Lithology: limestone; dolostone (dolomite); conglomerate; siltstone; shale; chert
Passaic Formation Quatzite-clast Conglomerate facies (Lower Jurassic and Upper Triassic) at surface, covers 0.8 % of this area
Passaic Formation Quartzite-clast Conglomerate facies - Quartzite conglomerate unit (JTrpcq) is reddish-brown pebble conglomerate, pebbly sandstone, and sandstone, in upward-fining sequences 1 to 2 m (3-6 ft) thick. Clasts are subangular to subrounded, quartz and quartzite in sandstone matrix. Sandstone is medium to coarse grained, feldspathic (up to 20 percent feldspar), and locally contains pebble and cobble layers. Conglomerate thickness exceeds 850 m (2,790 ft).
Lithology: conglomerate; sandstone
Clinopyroxene-Quartz-Feldspar Gneiss (Middle Proterozoic) at surface, covers 0.2 % of this area
Clinopyroxene-Quartz-Feldspar Gneiss - Pinkish-gray- or pinkish-buff-weathering, white to pale-pinkish-white or light-gray, fine- to medium-grained, massive to moderately well-layered gneiss composed of microcline, quartz, oligoclase, clinopyroxene, and trace amounts of epidote, biotite, titanite, and opaque minerals. Commonly interlayered with amphibolite or pyroxene amphibolite.
Lithology: paragneiss; amphibolite
Diorite (Middle Proterozoic) at surface, covers 1.0 % of this area
Diorite - Gray- to tan-weathering, greenish-gray to brownish-gray, medium- to coarse-grained, greasy-lustered, massive diorite containing andesine or oligoclase, clinopyroxene, hornblende, hypersthene, and sparse amounts of biotite and magnetite. Amphibolite layers common.
Lithology: diorite; amphibolite
Bloomsburg Red Beds (Upper Silurian) at surface, covers 0.9 % of this area
Bloomsburg Red Beds (White, 1883) (High Falls Shale of previous usage) - Grayish-red, thin- to thick-bedded, poorly to moderately well sorted, massive siltstone, sandstone, and local quartz-pebble conglomerate containing local planar to trough crossbedded laminations. Conglomerate consists of matrix-supported quartz pebbles in grayish-red, fine-grained sandstone matrix. Locally, near base of unit, is greenish-gray, light-gray, or grayish-orange, massive, planar tabular to trough crossbedded quartz sandstone to siltstone with subrounded grains. Lower part of formation marked by several upward-fining sequences of light-gray sandstone grading through grayish-red, fine-grained sandstone and siltstone to grayish-red, mudcracked siltstone and mudstone. Each sequence is 1 to 3 m (3-10 ft) thick. Lower contact placed at bottom of lowermost red sandstone. Thickness approximately 460 m (1,510 ft).
Lithology: siltstone; sandstone; conglomerate; mudstone
Leithsville Formation (Middle and Lower Cambrian) at surface, covers 0.8 % of this area
Leithsville Formation (Middle and Lower Cambrian) (Wherry, 1909) - Light- to dark-gray and lightolive-gray, fine- to medium-grained, thin- to medium-bedded dolomite. Grades downward through medium-gray, grayish-yellow, or pinkish-gray dolomite and dolomitic sandstone, siltstone and shale to medium-gray, medium-grained, medium-bedded dolomite containing quartz sand grains as stringers and lenses near the base. Lower contact gradational. Thickness ranges from 0 to 56 m (0-185 ft) due to erosion.
Lithology: dolostone (dolomite); shale; siltstone; sandstone
Pyroxene Gneiss (Middle Proterozoic) at surface, covers 0.6 % of this area
Pyroxene Gneiss - White- to tan-weathering, greenish-gray, fine- to medium-grained, well-layered gneiss containing oligoclase, clinopyroxene, variable amounts of quartz, and trace amounts of opaque minerals and titanite. Some phases contain scapolite and calcite. Commonly interlayered with pyroxene amphibolite or marble.
Lithology: paragneiss; amphibolite; marble
Biotite Granite (Middle Proterozoic) at surface, covers < 0.1 % of this area
Biotite Granite - Pink- to buff-weathering, light-pinkish-gray, medium-grained, massive, moderately foliated granite composed of microcline microperthite, quartz, oligoclase, and biotite.
Lithology: granite
Mt. Laurel Formation (Upper Cretaceous, upper Campanian) at surface, covers 1 % of this area
Mt. Laurel Formation - Sand, quartz, massive to crudely bedded, typically coarsens upward, interbedded with thin clay beds. Glauconite and feldspar are minor sand constituents. Muscovite and biotite are abundant near the base. Lower part of formation is a fine- to medium-grained, clayey, dark-gray, glauconitic (maximum 25 percent) quartz sand. Typically weathers to white or light yellow and locally stained orange brown by iron oxides. Small pebbles scattered throughout, especially in the west-central area. Locally, has small, rounded siderite concretions in the interbedded clay-sand sequence. Granules and gravel are abundant in the upper 1.5 m (5 ft). Upper beds are light gray and weather light brown to reddish brown. The Mount Laurel is 10 m (33 ft) thick from the Roosevelt quadrangle to the Runnemede quadrangle in the central sheet. Thickness varies in the northern part of the map area due, in part, to extensive interfingering of this formation with the underlying Wenonah Formation. Weller (1907) and Kummel (1940) recognized only about 1.5 m (5 ft) of the Mount Laurel in the north. In this report those beds are assigned to the overlying Navesink Formation. The interbedded sequence, the major facies in the north, ranges to about 4.5 m (15 ft) thick. These interbeds have well-developed large burrows (Martino and Curran, 1990), mainly Ophiomorpha nodosa, and less commonly Rosselia socialis. The Mount Laurel is gradational into the underlying Wenonah Formation. A transition zone of 1.5 m (5 ft) is marked by an increase in clay, silt, and mica into the Wenonah, especially in the west-central area of the central sheet. The oyster Agerostrea falcata occurs in the lower part of the formation. Exogyra cancellata and Belemnitella americana are abundant in upper beds in the west-central area of the central sheet (New Egypt quadrangle). The Mount Laurel Formation is of late Campanian age based on the assignment of Zone CC 22b to the formation by Sugarman and others (1995) and the occurrence of Exogyra cancellata near Mullica Hill, Gloucester County.
Lithology: sand; clay or mud; gravel
Serpentinite (Cambrian and Late Proterozoic) at surface, covers < 0.1 % of this area
Serpentinite - Light-yellowish-green to dark-green, fine-grained, massive serpentinite containing locally abundant magnetite where fresh. Contains a variety of serpentine minerals and alteration products where sheared or weathered. Exposed only along the Hudson waterfront in Hoboken but present elsewhere in boring logs.
Lithology: serpentinite
Longwood Shale (Middle (?) and Upper Silurian) at surface, covers < 0.1 % of this area
Longwood Shale (Darton, 1894) - Dark-reddish-brown, thin- to very thick bedded shale interbedded with cross-bedded, very dark red, very thin to thin-bedded sandstone and siltstone. Lower contact conformable. About 100 m (330 ft) thick.
Lithology: shale; sandstone; siltstone
Quartzite (Middle Proterozoic) at surface, covers < 0.1 % of this area
Quartzite - Light-gray, medium-grained, massive- to well-layered, vitreous, partly feldspathic quartzite having sparse flakes of graphite. Associated with potassium-feldspar gneiss (Yk), biotite-quartz-feldspar gneiss (Yb), pyroxene gneiss (Yp), Franklin Marble (Yf), and pyroxene-epidote gneiss (Ype).
Lithology: quartzite
Pyroxene-Epidote Gneiss (Middle Proterozoic) at surface, covers < 0.1 % of this area
Pyroxene-Epidote Gneiss - White- to light-gray-weathering, light-greenish-gray or greenish-buff, fine- to medium-grained, moderately layered and foliated gneiss composed principally of quartz, microcline, plagioclase, clinopyroxene, epidote, and sparse amounts of titanite. Some phases of this unit are quartz-rich. May be interlayered and probably related to pyroxene gneiss (Yp).
Lithology: paragneiss
Biotite-Quartz-Feldspar Gneiss (Middle Proterozoic) at surface, covers 0.7 % of this area
Biotite-Quartz-Feldspar Gneiss - Gray-weathering, locally rusty, gray to tan or greenish-gray, fine- to medium-coarse-grained, moderately layered and foliated gneiss that is variable in texture and composition. Composed of oligoclase, microcline microperthite, quartz, and biotite. Locally contains garnet, graphite, sillimanite, and opaque minerals.
Lithology: paragneiss
Berkshire Valley and Poxono Island Formations, undivided (Upper Silurian) at surface, covers < 0.1 % of this area
Berkshire Valley and Poxono Island Formations, undivided - Thickness ranges from 76 m (250 ft) at Greenwood Lake to 122 m (400 ft) in Longwood Valley. Berkshire Valley Formation (Barnett, 1970) - Commonly yellowish-gray weathering, medium-gray to pinkish-gray, very thin to thin-bedded fossiliferous limestone interbedded with gray to greenish-gray calcareous siltstone and silty dolomite, medium-gray to light-gray dolomite conglomerate, and grayish-black, thinly laminated shale. Lower contact conformable. Thickness ranges from 27 to 38 m (90-125 ft) thick. Poxono Island Formation, (White, 1882; Barnett, 1970) - Very thin to medium-bedded sequence of medium-gray, greenish-gray, or yellowish-gray, mud-cracked dolomite; light-green, pitted, medium-grained calcareous sandstone, siltstone, and edgewise conglomerate containing gray dolomite; and quartz-pebble conglomerate containing angular to subangular pebbles as much as 2 cm (0.8 in.) long. Interbedded grayish-green shales at lower contact are transitional into underlying Longwood Shale. Thickness ranges from 49 to 84 m (160-275 ft) thick.
Lithology: limestone; dolostone (dolomite); conglomerate; siltstone; shale; sandstone
Pyroxene Syenite (Middle Proterozoic) at surface, covers 0.3 % of this area
Pyroxene Syenite - Gray- to buff- or tan-weathering, greenish-gray, medium- to coarse-grained, massive, indistinctly foliated syenite composed of mesoperthite to microantiperthite, oligoclase and clinopyroxene. Contains sparse amounts of quartz, titanite, magnetite, and trace amounts of pyrite.
Lithology: syenite
Diabase (Jurassic) at surface, covers 0.8 % of this area
Diabase - Concordant to discordant, predominantly sheet-like intrusions of medium- to fine-grained diabase and dikes of fine-grained diabase; dark-greenish-gray to black; subophitic texture. Dense, hard, sparsely fractured rock composed mostly of plagioclase (An50-70), clinopyroxene (mostly augite), and magnetite-ilmenite. Orthopyroxene (En75-80) is locally abundant in the lower part of the sheets. Accessory minerals include apatite, quartz, alkali feldspar, hornblende, sphene, zircon, and rare olivine. Diabase in the map area was derived primarily from high-titanium, quartz-tholeiite magma. Sedimentary rocks within about 300 m (984 ft) above and 200 m (656 ft) below major diabase sheets are thermally metamorphosed. Red mudstone is typically altered to indurated, bluish-gray hornfels with clots or crystals of tourmaline or cordierite. Gray argillitic siltstone is typically altered to brittle, black, very fine grained hornfels. Sills are 365 to 400 m (1,197-1,312 ft) thick. Dikes range in thickness from 3 to 10 m (10-33 ft) and are many kilometers long.
Lithology: diabase
Buttermilk Falls Limestone and Onondaga Limestones, undivided (Middle Devonian) at surface, covers 0.1 % of this area
Buttermilk Falls Limestone and Onondaga Limestones, undivided - Buttermilk Falls Limestone in southwestern part of outcrop belt grades into Onondaga Limestone along strike to northeast. The transition occurs north of Millville. Buttermilk Falls Limestone (Middle Devonian) (Willard, 1938) - Light- to medium-light-gray-weathering, medium- to dark-gray, thin- to medium-bedded, fossiliferous, flaggy, clayey to silty limestone and nodular black chert. Lower contact grades downward through several meters (feet) of silty limestone to interbedded limestone and calcareous siltstone of the Schoharie Formation. Thickness is approximately 82 m (270 ft). Onondaga Limestone (Middle Devonian) (Vanuxem 1840) - Light-medium-gray- weathering, medium gray, fine-grained, thin- to thick-bedded fossiliferous limestone. Black chert more abundant in upper half of unit. Lower contact grades into interbedded limestone and calcareous siltstone of the Schoharie Formation. Thickness approximately 60 m (200ft).
Lithology: limestone; chert
Biotite-Plagioclase Gneiss (Middle Proterozoic) at surface, covers < 0.1 % of this area
Biotite-Plagioclase Gneiss - White- to light-gray weathering, greenish-gray, medium-grained, moderately well layered gneiss composed of biotite, plagioclase and accessory amounts of hornblende, clinopyroxene, and, locally, garnet.
Lithology: gneiss
Stockton Formation Cobble Conglomerate and Sandstone facies (Upper Triassic) at surface, covers < 0.1 % of this area
Stockton Formation Cobble Conglomerate and Sandstone facies - Predominantly medium- to coarse-grained, light-gray, light-grayish-brown, or yellowish- to pinkish-gray arkosic sandstone and medium- to fine-grained, violet-gray to reddish-brown arkosic sandstone; with lesser, reddish to purplish-brown, silty mudstone, argillaceous siltstone, and shale. Some coarse-grained sandstone in lower part contains thick beds of conglomerate (Trsc) which have been mapped in the vicinity of Stockton. Sandstone, deposited in high-gradient stream channels, is mostly planar bedded with scoured bases containing pebble lags and mudstone rip-up clasts. Upper part of channel beds are burrowed. Large-scale trough crossbeds occur in some very coarse grained sandstone beds; smaller scale trough and climbing-ripple cross lamination occur in the upper part of channel sequences and in finer grained sandstone beds. Typical floodplain mudstones are irregularly thin bedded and extensively burrowed. Floodplain beds are thicker and more numerous in the central Newark basin, near the Delaware River. Thickness of the unit (including Trsc) near Stockton is about 1,240 m (4,068 ft).
Lithology: conglomerate
Lockatong Formation red bed (Upper Triassic) at surface, covers 0.1 % of this area
Lockatong Formation red bed - Predominantly cyclic lacustrine sequences of silty, dolomitic or analcime-bearing argillite; laminated mudstone; silty to calcareous, argillaceous very fine grained sandstone and pyritic siltstone; and minor silty limestone, mostly light- to dark-gray, greenishgray, and black. Grayish-red, grayish-purple, and dark-brownish-red sequences (Trlr) occur in some places, especially in upper half. Two types of cycles are recognized: freshwater-lake (detrital) and alkaline-lake (chemical) cycles. Freshwater-lake cycles average 5.2 m (17 ft) thick. They consist of basal, transgressive, fluvial to lake-margin deposits that are argillaceous, very fine grained sandstone to coarse siltstone with indistinct lamination, planar or cross lamination, or are disrupted by convolute bedding, desiccation cracks, root casts, soil-ped casts, and tubes. Medial lake-bottom deposits are laminated siltstones, silty mudstones, or silty limestones that are dark gray to black with calcite laminae and grains and lenses, or streaks of pyrite; fossils are common, including fish scales and articulated fish, conchostracans, plants, spores, and pollen. Upper regressive lake margin, playa lake, and mudflat deposits are light- to dark-gray silty mudstone to argillitic siltstone or very fine grained sandstone, mostly thick bedded to massive, with desiccation cracks, intraformational breccias, faint wavy laminations, burrows, euhedral pyrite grains, and dolomite or calcite specks. Alkaline-lake cycles are similar to freshwater-lake cycles, but are thinner, averaging 3 m (10 ft), have fewer fossils (mainly conchostracans), and commonly have red beds, extensive desiccation features, and abundant analcime and dolomite specks in the upper parts of cycles. Thickness near Byram is about 1,070 m (3,510 ft). The formation thins to the southeast and northeast; thickness near Princeton is less than 700 m (2,297 ft).
Lithology: argillite; mudstone; sandstone; siltstone; limestone
Feltville Formation (Lower Jurassic) at surface, covers 0.4 % of this area
Feltville Formation - Mostly fine-grained, feldspathic sandstone, coarse siltstone, and silty mudstone, brownish-red to light-grayish-red. Fine-grained sandstone is moderately well sorted, cross laminated, and contains 15 percent or more feldspar; interbedded with mudstone, indistinctly laminated, bioturbated, and calcareous in places. A thin bed (0-2 m (0-7 ft) thick) of black, microlaminated carbonaceous limestone and gray calcareous mudstone occurs near the base and contains fish and plant fossils, and thermally mature hydrocarbons. Thickness of unit in the Sand Brook syncline is about 155 m (509 ft).
Lithology: siltstone; sandstone; fine-grained mixed clastic; mudstone; limestone
Preakness Basalt (Lower Jurassic) at surface, covers < 0.1 % of this area
Preakness Basalt - A thin, 2 to 8 m (6.6-26 ft) bed of siltstone (Jps) separates the lower flows.
Lithology: siltstone
Potomac Formation (Upper Cretaceous, lower Cenomanian) at surface, covers 1 % of this area
Potomac Formation - Predominantly clay to clay-silt, thinly laminated to thick-bedded, mottled red, white, and orange-brown, less commonly dark-gray and woody; interbedded with thin beds and lenses of very fine to medium-grained, massive, white to orange-brown, micaceous sand. Lithologies are typical of the shallow subsurface. Down dip, these lithologies interfinger with thin to thick beds of marine clay-silt, commonly glauconitic and locally shelly. Marine beds are most prevalent in the southernmost part of the southern sheet. Unit 3 was cored in its entirety at Freehold where it is approximately 75 m (246 ft) thick. In the core, the basal 6 m (20 ft) consists of red or mottled red and white clay interbedded with gravel and fine- to coarse-grained sand. The clay is pervaded by reddish-brown siderite. Most of the overlying beds consist of interbedded dark-colored clay, locally weathered to pale yellow or white, and fine- to medium-grained, light-colored sand. Layers that contain fine black carbonaceous material to large lignitized wood pieces are common in unit 3 in this core. At Toms River, the unit is about 60 m (197 ft) thick and consists of dark- to pale-gray clay, locally weathering to white or yellowish gray, and light-colored, micaceous sand. In general, the darker colored clay is more common in the upper part of the section. Locally, the sand has very small amounts of glauconite which may indicate some local marine influence during sedimentation. The age of unit 3 was determined from pollen in the nonmarine deposits and foraminifera in the marine sections. Typical forms found in Zone III in New Jersey are Ajatipollis sp. A, Tricolpites nemejci, T. vulgaris, Tricolporoidites bohemicus, Tricolporoidites sp. A, T. sp. B, and Tricolporopollenites sp. B (Doyle and Robbins, 1977). In the marine facies, Petters (1976) reports a planktic foraminiferal suite containing Praeglobotruncana delrioensis and Rotalipora greenhornensis. Both the pollen and foraminiferal assemblages suggest an early Cenomanian age.
Lithology: clay or mud; silt; sand
Epidote Gneiss (Middle Proterozoic) at surface, covers < 0.1 % of this area
Epidote Gneiss - Light-gray- to pinkish-white-weathering, light-grayish-pink to pinkish-white, medium-grained, moderately layered and foliated gneiss containing quartz, microcline, and epidote. Some phases contain scapolite. May be interlayered with and related to potassium-feldspar gneiss (Yk), and (or) clinopyroxene-quartz-feldspar gneiss (Ymp). Two elongate bodies mapped east of Franklin.
Lithology: paragneiss
Towaco Formation Conglomerate and Sandstone facies (Lower Jurassic) at surface, covers < 0.1 % of this area
Towaco Formation Conglomerate and Sandstone facies - Conglomerate and conglomeratic sandstone with subrounded quartzite and quartz clasts in matrix of light-red sand to brownish-red silt (Jtc) interfingers with rocks of the Towaco Formation north and west of New Vernon.
Lithology: conglomerate; sandstone; siltstone
Martinsburg Formation (Upper and Middle Ordovician) (Upper and Middle Ordovician) at surface, covers 0.1 % of this area
Martinsburg Formation (Middle and Upper Ordovician) - Yellowish-gray weathering, light-olive- to dark-gray, phyllonitic shale containing thin, discontinuous silty lenses. Crops out in two locations along the Reservoir fault north of Bowling Green Mountain (Barnett, 1976; Herman and Mitchell, 1991). Contact relations and thickness unknown.
Lithology: shale; siltstone
Towaco Formation (Lower Jurassic) at surface, covers 0.9 % of this area
Towaco Formation (Olsen, 1980) - Reddish-brown to brownish-purple, fine- to medium-grained micaceous sandstone, siltstone, and silty mudstone in upward-fining sequences 1 to 3 m (3-10 ft) thick. Distributed throughout formation are eight or more sequences of gray to greenish- or brownish-gray, fine-grained sandstone, siltstone and calcareous siltstone and black, microlaminated calcareous siltstone and mudstone containing diagnostic pollen, fish and dinosaur tracks. Sandstone is commonly trough cross laminated; siltstone is commonly planar laminated or bioturbated, but can be indistinctly laminated to massive. Thermally metamorphosed into hornfels where in contact with Hook Mountain Basalt. Conglomerate and conglomeratic sandstone with subrounded quartzite and quartz clasts in matrix of light-red sand to brownish-red silt (Jtc) interfingers with rocks of the Towaco Formation north and west of New Vernon. Maximum thickness is about 380 m (1,250 ft).
Lithology: sandstone; siltstone; fine-grained mixed clastic; conglomerate
Felsic to mafic gneiss (Precambrian) at surface, covers < 0.1 % of this area
Felsic to mafic gneiss - Light, medium grained; predominantly quartz and feldspar of igneous origin.
Lithology: felsic gneiss; mafic gneiss; orthogneiss
Stockton Formation Cobble Conglomerate and Sandstone facies (Upper Triassic) at surface, covers < 0.1 % of this area
Stockton Formation Cobble Conglomerate and Sandstone facies - Unit is coarser near Newark basin border fault, where poorly exposed, reddish-brown to pinkish-white, medium- to coarse-grained, feldspathic pebbly sandstone and conglomerate (Trss) and pebble to cobble quartzite conglomerate (Trscq).
Lithology: sandstone; conglomerate
Beekmantown Group, Lower Part (Lower Ordovician) at surface, covers 0.7 % of this area
Beekmantown Group, Lower Part (Clarke and Schuchert, 1899) - Very thin to thick-bedded, interbedded dolomite and minor limestone. Upper beds are light-olive-gray to dark-gray, fine- to medium-grained, thin- to thick-bedded dolomite. Middle part is olivegray-, light-brown-, or dark-yellowish-orange- weathering, dark-gray, aphanitic to fine-grained, laminated to medium-bedded dolomite and light-gray to light-bluish-gray-weathering, medium-dark- to dark-gray, fine-grained, thin- to medium-bedded limestone, that is characterized by mottling with reticulate dolomite and light-olive-gray to grayish-orange, dolomitic shale laminae surrounding limestone lenses. Limestone grades laterally and down section into medium- gray, fine-grained dolomite. Lower beds consist of medium-light- to dark-gray, aphanitic to coarse-grained, laminated to medium-bedded, locally slightly fetid dolomite having thin black chert beds, quartz-sand laminae, and oolites. Lenses of light-gray, very coarse to coarse-grained dolomite and floating quartz sand grains and quartz-sand stringers at base of sequence. Lower contact placed at top of distinctive medium-gray quartzite. Contains conodonts of Cordylodus proavus to Rossodus manitouensis zones of North American Midcontinent province as used by Sweet and Bergstrom (1986). Unit Obl forms Stonehenge Formation of Drake and Lyttle (1985) and Drake and others (1985), upper and middle beds are included in Epler Formation, and lower beds are in Rickenbach Dolomite of Markewicz and Dalton (1977). Unit is about 183 m (600 ft) thick.
Lithology: dolostone (dolomite); limestone; chert
Minisink Limestone and New Scotland Formation, undivided (Lower Devonian) at surface, covers < 0.1 % of this area
Minisink Limestone and New Scotland Formation, undivided - Minisink Limestone (Epstein and others, 1967) - Light-medium-gray-weathering, medium-gray, fine-grained, medium-bedded, partly massive, argillaceous fossiliferous limestone. Some nodules and lenses of purer limestone occur locally. Lower contact gradational. Thickness uniformly 7 m (23 ft). New Scotland Formation (Clarke and Schuchert, 1899) - Upper part is dark-gray, very fine grained, laminated to thin-bedded siliceous shale containing pods of medium-dark-gray, very fine grained limestone; scattered thin beds and lenses of medium-gray, fine-grained argillaceous fossiliferous limestone; and small dark-gray chert nodules. Lower part is medium-dark-gray, thin-bedded, siliceous, fossiliferous calcareous shale. Contains thin beds and lenses of medium-gray, fine-grained, highly fossiliferous, argillaceous limestone containing nodules, lenses and, locally, irregular beds of dark-gray chert. Lower contact abrupt and placed at top of calcareous quartz sandstone. Total thickness is approximately 23 m (75 ft).
Lithology: limestone; shale; chert
Stockton Formation (Upper Triassic) at surface, covers 1 % of this area
Stockton Formation - Predominantly medium- to coarse-grained, light-gray, light-grayish-brown, or yellowish- to pinkish-gray arkosic sandstone and medium- to fine-grained, violet-gray to reddish-brown arkosic sandstone; with lesser, reddish to purplish-brown, silty mudstone, argillaceous siltstone, and shale. Some coarse-grained sandstone in lower part contains thick beds of conglomerate (Trsc) which have been mapped in the vicinity of Stockton. Sandstone, deposited in high-gradient stream channels, is mostly planar bedded with scoured bases containing pebble lags and mudstone rip-up clasts. Upper part of channel beds are burrowed. Large-scale trough crossbeds occur in some very coarse grained sandstone beds; smaller scale trough and climbing-ripple cross lamination occur in the upper part of channel sequences and in finer grained sandstone beds. Typical floodplain mudstones are irregularly thin bedded and extensively burrowed. Floodplain beds are thicker and more numerous in the central Newark basin, near the Delaware River. Thickness of the unit (including Trsc) near Stockton is about 1,240 m (4,068 ft).
Lithology: arkose; fine-grained mixed clastic; siltstone; shale
Mount Eve Granite (Middle Proterozoic) at surface, covers < 0.1 % of this area
Mount Eve Granite (Drake and others, 1991a) - Light-pinkish-gray or grayish-tan-weathering, light-gray to pinkish-gray, medium- to coarse-grained granite containing microcline microperthite, quartz, oligoclase, and biotite. Common accessory minerals include hornblende, biotite, magnetite, and allanite. Most of the rock is a syenogranite. Upper intercept U-Pb age of 1,020 +/- 4 Ma (Drake and others, 1991a). Occurs in Pochuck Mountain area along New York boundary.
Lithology: granite
Shrewsbury Member of the Red Bank Formation (Upper Cretaceous, upper and middle Maastrichtian) at surface, covers 0.8 % of this area
Shrewsbury Member - Sand, quartz, fine- to coarse-grained, somewhat clayey and micaceous, mostly massive with local small-scale crossbedding, light-yellow to red or dark-brown, slightly glauconitic at the base. Feldspar is a minor sand constituent. The Shrewsbury is extensively burrowed but is otherwise unfossiliferous. Locally, small "Callianassa"-type burrows are present. Maximum thickness is over 30 m (98 ft) in the highlands near Matawan. Unit thins southwestward and pinches out near Arneytown, Ocean County. The transition to the underlying Sandy Hook Member occurs within several feet and is characterized by an increase in clay, quartz, silt, mica, and fine pieces of wood downward.
Lithology: sand; clay or mud
Passaic Formation Conglomerate and Sandstone facies (Lower Jurassic and Upper Triassic) at surface, covers 1.0 % of this area
Passaic Formation Conglomerate and Sandstone facies - Conglomeratic sandstone (JTrpsc) is brownish-red pebble conglomerate, medium- to coarse-grained, feldspathic sandstone and micaceous siltstone; unit is planar to low-angle trough cross laminated, burrowed, and contains local pebble layers. Unit forms upward-fining sequences 0.5 to 2.5 m (1.6-8 ft) thick. Conglomeratic sandstone thickness exceeds 800 m (2,625 ft).
Lithology: conglomerate; sandstone; siltstone
Bushkill Member (Middle Ordovician) at surface, covers 0.7 % of this area
Bushkill Member (Drake and Epstein, 1967) - Interbedded medium- to dark gray, thinly laminated to thick-bedded shale and slate and less abundant medium-gray to brownish-gray, laminated to thin-bedded siltstone. To the southwest, fine-grained, thin dolomite lenses occur near base. Complete turbidite sequences (Bouma, 1962) occur locally, but basal cutout sequences (Tbcde, Tcde or Tde) dominate. Conformable lower contact is placed at top of highest shaly limestone; elsewhere, lower contact is commonly strain slipped. Correlates with graptolite Climacograptus bicornis to Corynoides americanus zones of Riva (1969, 1974) (Parris and Cruikshank, 1992). Thickness ranges from 1,250 m (4,100 ft) in Delaware River Valley to 457 m (1,500 ft) at New York State line.
Lithology: slate; shale; siltstone; dolostone (dolomite)
Granophyre (Early Jurassic) at surface, covers < 0.1 % of this area
Granophyre - Fine-grained to aphanitic dikes; medium- to coarsegrained, subophitic discordant stock-like intrusions of dark-greenish-gray to black diabase; and plugs of dark gray, concordant to discordant sheetlike, medium- to coarse-grained, quartz-rich to albite-rich granophyre (map unit Jg). The chilled margins of diabase masses are aphanitic to very fine grained. Diabase is dense, hard, and sparsely fractured. It is composed mostly of plagioclase (An50-70), clinopyroxene (mostly augite) and magnetite +/- ilmenite. Accessory minerals include apatite, quartz, alkali feldspar, hornblende, titantite, and zirocon. Olivine is rare. Within about 200 m (655 ft) above and 150 m (490 ft) below the large diabase sheets, red mudstones are typically metamorphosed into indurated, bluish-gray hornfels commonly with clots or crystals of tourmaline or cordierite, whereas argillitic siltstone is metamorphosed into brittle, black, very fine grained hornfels, Sheetlike intrusions are as much as 360 to 400 m (1,180-1,310 ft) thick. Dikes range in thickness from 3 to 15 m (10-50 ft) and several kilometers (miles) long. Thickness of the stocklike bodies is unknown.
Lithology: granitoid
Manasquan Formation (lower Eocene, Ypresian) at surface, covers 0.3 % of this area
Manasquan Formation - Clay to clay-silt, massive to finely laminated, green to gray-green, extensively bioturbated. Calcareous microfossils are abundant in this unit. In the northwestern outcrop belt and shallow subsurface of the central sheet, the lower beds of the Manasquan Formation consist of a maximum of 10 m (33 ft) of fine- to coarse-grained, somewhat clayey, bluish-green glauconitic quartz sand. No calcareous macrofossils were found in this lithology. The sand minerals in the basal sand facies, excluding glauconite, consist of quartz, feldspar (10 to 25 percent), and siliceous rock fragments (a few percent). The glauconitic quartz sand is overlain to the southwest by a light- to dark-green, locally glauconitic, sandy clay-silt. This clay-silt is present at the base of the unit in the shallow subsurface. Eastward and in the intermediate subsurface, the Manasquan is primarily a clayey glauconite sand. In the deep subsurface, the Manasquan is primarily a massive to finely laminated, lightyellow clay-silt that has high concentrations of calcareous microfossils and has several hard indurated layers. In general, the formation thickens to the southeast where it is more than 60 m (197 ft) thick. The basal contact with the underlying Vincentown Formation is sharp and contains a thin zone, typically 0.61 m (2 ft) thick, of reworked glauconite sand, phosphatic debris, and sparse quartz granules. Gamma-ray logs through the Manasquan Formation have a large gamma spike along the basal contact. The age of the Manasquan was determined from calcareous nannofossils and, to a lesser degree, from foraminifera. The lower part of the Manasquan is assigned to the upper part of Zone NP 9 on the basis of the calcareous nannofossils Campylosphaera dela and Lophodolithus nascens and the absence of Zone NP 10 species. The upper part of the formation lies within Zone NP 13. This zone is characterized by the absence of Rhomboaster orthostylus and the presence of Discoaster lodoensis (Poore and Bybell, 1988). The foraminifera Planorotalites palmerae, which is present in this unit, has a range that correlates with the lower part of Zone NP 13 (Poore and Bybell, 1988).
Lithology: clay or mud; silt; sand
Manhattan Schist (Lower Cambrian and (or) Late Proterozoic) at surface, covers < 0.1 % of this area
Manhattan Schist (Hall, in press) - Medium-dark gray, medium- to coarse-grained schist and gneiss composed of biotite, muscovite, quartz, and plagioclase, and local accessory minerals sillimanite, kyanite, tourmaline, and garnet. Contains some interlayered amphibolite. Unit is not exposed in the map area, but is present in boring logs.
Lithology: schist; gneiss; amphibolite
Migmatite (Middle Proterozoic) at surface, covers < 0.1 % of this area
Migmatite - Mixed rock consisting of amphibolite containing veins, lenses, layers, and irregular clots of albite-oligoclase granite or microperthite alaskite.
Lithology: migmatite
Jutland Klippe Sequence Unit B (Middle Ordovician) at surface, covers < 0.1 % of this area
Jutland Klippe Sequence Unit B of Perissoratis and others (1979) - Heterogeneous sequence of interbedded red, green, tan and gray shale; interlaminated dolomite and shale; interbedded fine-grained graywacke siltstone and beds or lenses of sandstone; light-gray to pale-pinkish-gray quartzite; and interbedded fine-grained, thin-bedded limestone and red and green shale. Limestone locally resembles an intraformational conglomerate because it is disrupted, boudinaged, and surrounded by shale beds. Lower contact gradational and within interbedded sequence of thin- to medium-bedded sandstone, siltstone, and limestone. Perissoratis and others (1979) placed this contact at boundary between graptolite faunas Isograptus caduceus and Paraglossograptus etheridgei of Berry (1968). The youngest graptolites occur within Climacograptus bicornis zone of Berry (1968). Some shale beds contain conodonts (Ethington and others, 1958; Karklins and Repetski, 1989) and brachiopod fragments. Carbonate and pelitic rocks locally contain conodonts of Prioniodus triangularis to Pygodus anserinus faunas of North Atlantic Realm. Thickness varies due to structural complexity, but may be about 460 to 550 m (1,500-1,800 ft).
Lithology: shale; dolostone (dolomite); siltstone; sandstone; quartzite; limestone
Hornblende gneiss (Precambrian) at surface, covers < 0.1 % of this area
Hornblende gneiss - Dark, medium grained; includes some rocks of probable sedimentary origin.
Lithology: mafic gneiss; paragneiss
Nepheline syenite (Early Silurian? and Late Ordovician) at surface, covers < 0.1 % of this area
Nepheline syenite - Medium- to dark-gray, medium- to coarse-grained, alkalic to alkalic-calcic nepheline syenite. Composed principally of nepheline, orthoclase, biotite, and clinopyroxene, and accessory minerals are magnetite, apatite, titanite, zircon, and pyrite. Restricted to two small bodies northwest of Beemerville. Intrudes the Martinsburg Formation, but appears to be unconformably overlain by the Shawangunk Formation. K-Ar and Rb-Sr ages of 435 +/- 20 Ma from biotite (Zartman and others, 1967) and a fission track date from titanite of 422 +/- 14 Ma (Eby and others, 1992) suggest emplacement in Late Ordovician to Early Silurian.
Lithology: nepheline syenite
Raritan Formation (Upper Cretaceous, upper Cenomanian) at surface, covers 0.7 % of this area
Raritan Formation - Clay, silty, massive, dark-gray, shelly. Unit is generally restricted to the deep subsurface and only subcrops in the northern part of the central sheet. Petters (1976) proposed a new formation, the Bass River Formation, which included the Raritan as well as the lowermost part of the Magothy and the uppermost part of the Potomac Formation, unit 3. In this report, the name Bass River is not used. Thickness values were obtained from interpretations of geophysical logs from the few drillholes that penetrated this formation; consequently, these values are, at best, speculative. It is estimated that the Raritan is at most 100 m (328 ft) thick in the southernmost part of New Jersey. The formation contains both nonmarine and marine facies. The Freehold drillhole shows the best section containing both facies. In this drillhole the Raritan is approximately 60 m (197 ft) thick. The lower 12 m (39 ft) consists of interbedded, fine- to medium-grained, thin- to thick-bedded, light to dark-colored quartz sand and light- to dark-colored clay or clayey silt. Small to large pieces of lignitized wood are characteristic of and common to abundant in these beds. The middle 30 m (98 ft) consists of laminated to thinly bedded, dark-gray, micaceous clay and fine-grained, light-colored, micaceous quartz sand. Reddish-brown secondary cementation is common in the strata of this interval. Lignitized wood fragments are also locally abundant in these beds but on average the wood pieces are much smaller than those seen in the basal beds. The upper 18 m (59 ft) also is dominated by the laminated to thin-bedded sequences of micaceous clay and quartz sand but has small amounts of glauconite sand. A thin layer of large fossils (primarily Exogyra woolmani) is present in these upper beds. At the very top of this interval some of the beds are cemented by siderite. In general, the Raritan appears to be fluvial in the lower part, marginal marine in the middle, and marine at the top. North and west of the Freehold drillhole the Raritan is mostly interbedded nonmarine crossbedded sand and black to variegated clay. At Island Beach, southwest of Freehold, the Raritan is wholly marine and consists largely of dark-gray, shelly, micaceous clay at the base and fine-grained, dark-gray, shelly, micaceous clay at the top. It is assumed that the Raritan is late Cenomanian to possibly early Turonian in age as determined from northern New Jersey sections. In outcrop, the Raritan is early late Cenomanian in age on the basis of ammonites (Cobban and Kennedy, 1990). Pollen from these outcrops belongs to the Complexiopollis-Atlantopollis Assemblage Zone (zone IV, Christopher, 1979). Downdip, Petters (1976) reports the planktic foraminifer Marginotruncana helvetica, a middle Turonian marker, from beds assigned to pollen zone IV at Toms River, Ocean County.
Lithology: clay or mud; silt; sand
Green Pond Conglomerate (Lower (?) and Middle Silurian) at surface, covers 0.2 % of this area
Green Pond Conglomerate (Rogers, 1836) - Medium- to coarse-grained quartz-pebble conglomerate, quartzitic arkose and orthoquartzite, and thin- to thick-bedded reddish-brown siltstone. Grades downward into gray, very dark-red, or grayish-purple, medium- to coarse-grained, thin- to very thick bedded pebble to cobble conglomerate containing clasts of red shale, siltstone, and chert; yellowish-gray sandstone and chert; dark-gray shale and chert; and white-gray and pink milky quartz. Quartz cobbles are as long as 10 cm (4 in.), and rare red shale clasts as much as 46 cm (18 in.) across. Milky quartz pebbles average 2.5 cm (1 in.) in length. Red arkosic quartz-pebble conglomerate and quartzite are more abundant than gray and grayish-green quartzite. Unconformably overlies Martinsburg Formation, Allentown Dolomite, Leithsville Formation, or Proterozoic rocks. About 305 m (1000 ft) thick.
Lithology: conglomerate; arkose; siltstone; quartzite; shale; chert
Shawangunk Formation (Middle and Lower Silurian) at surface, covers 0.4 % of this area
Shawangunk Formation (Mather, 1840; Epstein and Epstein, 1972) - Upper part is medium- to medium-dark-gray, or dark-greenish-gray, medium- to thick-bedded sandstone and pebble conglomerate having well rounded grains, some of which are limonite stained. Conglomerate consists of matrix-supported quartz and subordinate shale pebbles as long as 5 cm (2 in.) in poorly to well-sorted, planar tabular to trough crossbedded sandstone. Local black to dark-greenish-gray, thin-bedded shale near upper contact. Middle part, occurring in southwest and sporadically in northeast, is light- to medium-dark-gray, greenish-gray, interbedded thin- to medium-bedded, planar tabular to trough cross-bedded shale and sandstone. Grains are well rounded and moderately to well sorted. Contains sparse graphite flakes. Lower part is light- to medium-gray to light-olive-gray, thin- to thick-bedded quartz and feldspathic sandstone, quartzite, and quartz-pebble conglomerate, which is matrix-supported, poorly to well sorted, cross to planar bedded. Clasts are primarily quartz and sparse dark-gray argillite and black chert. Sandstone is feldspathic and locally approaches an arkose in compostion. Lower contact unconformable and, at places, is a fault of small displacement. Thickness approximately 427 m (1,400 ft).
Lithology: sandstone; conglomerate; shale
Pyroxene-hornblende-quartz-plagioclase gneiss (Middle Proterozoic) at surface, covers < 0.1 % of this area
Pyroxene-hornblende-quartz-plagioclase gneiss.
Lithology: mafic gneiss
Bellvale Sandstone (Middle Devonian) at surface, covers 0.2 % of this area
Bellvale Sandstone (Bellvale Flags of Darton, 1894; Willard, 1937) - Upper beds are grayish-red to grayish-purple sandstone containing quartz pebbles as large as 3 cm (1.2 in) in diameter. Lower beds are light-olive-gray- to yellowish-gray- and greenish-black-weathering, medium-gray to medium-bluish-gray very thin to very thick bedded siltstone and sandstone cross-bedded, graded and interbedded with black to dark-gray shale that is locally fossiliferous. More sandstone in upper beds becomes finer downward. Lower contact conformable and placed where beds thicken and volume of shale and siltstone are about equal. The unit is 535 to 610 m (1,750-2,000 ft) thick.
Lithology: sandstone; siltstone; shale
Kanouse and Esopus Formations and Connelly Conglomerate, undivided (Lower Devonian) at surface, covers < 0.1 % of this area
Kanouse and Esopus Formations and Connelly Conglomerate, undivided - Kanouse Sandstone (Kummel, 1908) - Medium-gray, light-brown, and grayish-red, fine- to coarse-grained, thin- to thick-bedded sparsely fossiliferous sandstone and pebble conglomerate. Basal conglomerate beds are interbedded with siltstone similar to the upper part of the Esopus Formation and contain well-sorted, subangular to subrounded, gray and white quartz pebbles less than 1 cm (0.4 in.) long. Lower contact gradational. About 14 m (46 ft) thick. Esopus Formation - (Vanuxem, 1842; Boucot, 1959) - Light- to dark-gray, laminated to thin-bedded siltstone interbedded with dark-gray to black mudstone, dusky-blue sandstone and siltstone, and yellowish-gray fossiliferous siltstone and sandstone. Lower contact probably conformable with the Connelly Conglomerate. The formation is about 100 m (330 ft) thick at Greenwood Lake and estimated at 55 m (180 ft) thick in Longwood Valley. Connelly Conglomerate (Chadwick, 1908) - Grayish-orange weathering, very light gray to yellowish-gray, thin-bedded quartz-pebble conglomerate. Quartz pebbles average 1 to 2 cm (0.4-0.8 in.), are subrounded to well rounded, and well sorted. The unit unconformably overlies the Berkshire Valley Formation. About 11 m (36 ft) thick.
Lithology: siltstone; sandstone; mudstone; conglomerate
Unnamed Formation at Cape May (upper Pliocene) at surface, covers 1 % of this area
Unnamed Formation at Cape May - Interbedded gravel, sand, and clay, massive to thickbedded. Informal unit described from a corehole at the Cape May Airport. The lower 18.3 m (60 ft) consists of interbedded gravel; medium- to very coarse grained, poorly sorted sand; and thin to thick beds of medium- to dark-gray, very woody clay. Gravel clasts are typically less than 0.64 mm (0.025 in) in diameter. The upper 12.2 m (40 ft) consists of a thick-bedded, medium-gray, extensively bioturbated clay-silt, which is overlain by an extensively burrowed, fine- to medium-grained glauconitic (about 5 percent) quartz sand. Quartz and siliceous rock fragments compose most sand grains. Feldspar is present in most samples but usually constitutes less than 10 percent of the sand fraction. No calcareous macrofossils were found in the burrowed intervals. Unit is known only to occur on the Cape May peninsula where it lies within a large channel. The unit is about 60 m (197 ft) in maximum thickness. The contact with the underlying Belleplain Member of the Kirkwood Formation is sharp and unconformable; a basal gravel bed as much as 1 m (3 ft) thick is present along the contact. The pollen assemblage in the lower part of the unit is dominated by pine and oak with somewhat lesser amounts of hickory and basswood. Spruce, hemlock, beech, alder, and black gum are minor constituents. Traces of fir, willow, birch, and sweet gum are present, as is exotic Engelhardia. The nonarborial pollen are a Multisia-type composite of the present-day Andean provenance which indicate an exotic cool climate. The lower assemblage suggests a cool-temperate climatic regimen. The pollen assemblage in the upper beds is dominated by oak and hickory with minor amounts of basswood, sweet gum, pine, and Multisia-type composite. Traces of cedar, willow, birch, alder, grass, and Sphagnum spores also are present. This assemblage probably represents a temperate climatic regimen (Les Sirkin, Adelphi University, written commun., 1991). The low percentage of exotic species is characteristic of the late Pliocene, and therefore, the unnamed unit at Cape May may be equivalent to the Beaverdam Formation of the Delmarva Peninsula of Delaware, Maryland, and Virginia.
Lithology: gravel; sand; clay or mud; silt
Franklin Marble (Precambrian) at surface, covers < 0.1 % of this area
Franklin Marble - White, coarsely crystalline; disseminated graphite flakes.
Lithology: marble
Gabbro (Middle Proterozoic) at surface, covers < 0.1 % of this area
Gabbro - Medium- to coarse-crystalline, medium- to dark-gray foliated rock composed principally of plagioclase (An35) and clinopyroxene. Contains minor amounts of garnet, biotite, and sulfide. The rock is more siliceous than typical gabbros.
Lithology: gabbro
Lockatong Formation - Sandstone and Conglomerate facies (Upper Triassic) at surface, covers < 0.1 % of this area
Sandstone and Conglomerate Sandstone facies - Unit Trla interfingers laterally and gradationally with quartz sandstone and conglomerate (Trls) and quartzite conglomerate (Trlcq) near Triassic border fault in southwestern area of map.
Lithology: sandstone; conglomerate
Cornwall Shale (Middle Devonian) at surface, covers 0.1 % of this area
Cornwall Shale (Hartnagel, 1907) - Black to dark-gray, very-thin- to thickbedded, fissile shale, fossiliferous, interbedded with medium-gray and light-olive-gray to yellowish-gray, laminated to very-thin-bedded siltstone, that increases in upper part of unit. Lower contact probably conformable. About 290 m (950 ft) thick.
Lithology: shale; siltstone
Garnet-biotite-quartz-feldspar gneiss (Middle Proterozoic) at surface, covers < 0.1 % of this area
Garnet-biotite-quartz-feldspar gneiss - quartzite, quartz-feldspar gneiss, calcsilicate rock.
Lithology: gneiss; quartzite; calc-silicate rock
Ouachitite breccia (Early Silurian? and Late Ordovician) at surface, covers < 0.1 % of this area
Ouachitite breccia - Medium-dark-gray, fine-grained ouachitite (olivine-free biotite lamprophyre) containing pebble- to cobble-size xenoliths of Middle Proterozoic rock, dolomite of the Kittatinny Supergroup(?), the Martinsburg Formation, and autoliths of potassic syenite, lamprophyre, and carbonatite. Found in numerous diatremes in the Beemerville area; largest of at Rutan Hill.
Lithology: lamprophyre; dolostone (dolomite); syenite; intrusive carbonatite
Syenite Gneiss (Middle Proterozoic) at surface, covers < 0.1 % of this area
Syenite Gneiss - Light-pinkish-white- to buff-white-weathering, greenish-gray, medium-grained, moderately foliated rock consisting of two distinct phases: hornblende syenite gneiss containing microcline microperthite, oligoclase, hornblende, and opaque minerals; and pyroxene syenite gneiss containing microcline microperthite, oligoclase, clinopyroxene, accessory amounts of titanite, and opaque minerals. Despite the co-mingling of these two phases, they appear to belong respectively to the Byram and Lake Hopatcong Intrusive Suites. In Hamburg Mountain area.
Lithology: orthogneiss
Rondout and Decker Formations, undivided (Lower Devonian and Upper Silurian) at surface, covers < 0.1 % of this area
Rondout and Decker Formations, undivided - Rondout Formation (Clarke and Schuchert, 1899) - Upper part is medium-gray weathering, medium-dark-gray, very fine to fine-grained, medium-bedded, fossiliferous, argillaceous limestone. Middle part is light-medium-gray-weathering, medium-gray, laminated to medium-bedded, argillaceous dolomite. Locally contains deep desiccation polygons. Lower part is medium-gray-weathering, medium- to dark-gray, very fine to medium-grained, medium-bedded fossiliferous limestone. Silurian-Devonian boundary placed in middle of formation (Denkler and Harris, 1988). Lower contact abrupt and placed at top of highest calcareous quartz sandstone. Thickness approximately 12 m (40 ft). Decker Formation (White, 1882) - Light-gray- to yellowish-gray-weathering, light- to medium-gray, calcareous quartz siltstone, sandstone, and fine-pebble conglomerate locally interbedded with fossiliferous medium-gray, medium- to coarse-grained limestone and very fine grained, thin- to medium-bedded dolomite. Lower contact gradational. Thickness varies from 15 m (50 ft) near Duttonville to 25 m (82 ft) at Wallpack Center.
Lithology: limestone; dolostone (dolomite); siltstone; sandstone; conglomerate
Rickenbach Formation (Ordovician) at surface, covers < 0.1 % of this area
Rickenbach Formation - Gray, very finely to coarsely crystalline, laminated dolomite; dark-gray chert in irregular beds, stringers, and nodules; bands of quartz sand grains in lower half.
Lithology: dolostone (dolomite); chert
Graywacke and shale of Martinsburg Formation (Ordovician) at surface, covers < 0.1 % of this area
Graywacke and shale of Martinsburg Formation - Abundant impure sandstone (graywacke) interbeds.
Lithology: graywacke
Ridgeley Formation through Coeymans Formation, undivided (Devonian) at surface, covers < 0.1 % of this area
Ridgeley Formation through Coeymans Formation, undivided - In descending order: Ridgeley Formation--white siliceous sandstone; Shriver Chert--gray siltstone and shale and dark-gray chert; Port Ewen Shale--dark-gray calcareous siltstone and shale; Minisink Limestone--dark-gray clayey limestone; New Scotland Formation--dark-gray fossiliferous shale and clayey limestone; Coeymans Formation--gray, clayey to sandy limestone.
Lithology: sandstone; siltstone; shale; limestone; chert
Feltville Formation Conglomerate and Sandstone facies (Lower Jurassic) at surface, covers < 0.1 % of this area
Feltville Formation Conglomerate and Sandstone facies - Near Oakland, subrounded pebbles to cobbles of quartzite and quartz in a red siltstone and sandstone matrix (Jfc) interfinger with sandstone and siltstone of the Feltville Formation.
Lithology: conglomerate; sandstone; siltstone
Quartz-pebble Conglomerate (Lower Jurassic) at surface, covers < 0.1 % of this area
Quartz-pebble Conglomerate - Reddish-brown to brownish-purple, fine-grained sandstone, siltstone, and mudstone; sandstone commonly micaceous, interbedded with siltstone and mudstone in fining-upward sequences mostly 1.5 to 4 m (5-13 ft) thick. Red, gray and brownish-purple siltstone and black, blocky, partly dolomitic siltstone and shale common in lower part. Irregular mudcracks, symmetrical ripple marks, and burrows, as well as gypsum, glauberite, and halite pseudomorphs are abundant in red mudstone and siltstone. Gray, fine-grained sandstone may have carbonized plant remains and reptile footprints in middle and upper parts of unit. Near Morristown, beds of quartz-pebble conglomerate (unit Jbcq) as much as 0.5 m (1.6 ft) thick interfinger with beds of sandstone, siltstone, and shale. Northeast of Boonton, beds of quartz-pebble conglomerate (not mapped separately as Jbcq) occur locally with conglomerate containing abundant clasts of gneiss and granite in matrix of reddish-brown sandstone and siltstone. Maximum thickness is about 500 m (1,640 ft).
Lithology: conglomerate
Mahantango Formation (Devonian) at surface, covers < 0.1 % of this area
Mahantango Formation - Gray, brown, and olive shale and siltstone; marine fossils. Includes the following members, in descending order: Tully-argillaceous limestone; Sherman Ridge, Montebello (sandstone), Fisher Ridge, Dalmatia, and Turkey Ridge. In south-central Pennsylvania, includes Clearville, Frame, Chaneysville, and Gander Run Members. Characterized by coarsening-upward cycles.
Lithology: shale; siltstone; limestone; sandstone
Allentown Formation (Cambrian) at surface, covers < 0.1 % of this area
Allentown Formation - Medium- to medium-dark-gray, thick-bedded dolomite and impure limestone; dark-gray chert stringers and nodules; laminated; oolitic and stromatolitic; some orange-brown-weathering calcareous siltstone at base.
Lithology: dolostone (dolomite); limestone; chert; siltstone
Leithsville Formation (Cambrian) at surface, covers < 0.1 % of this area
Leithsville Formation - Medium- to dark-gray, crystalline dolomite, light-olive-gray in places, weathering to light gray and yellowish brown; massive bedded; oolitic; pink to gray, mottled chert and dark-gray chert; thin shale and dolomitic shale interbeds; scattered sand grains; upper part is very shaly.
Lithology: dolostone (dolomite); shale; chert; sand
Jutland Klippe Sequence, undifferentiated (Middle Ordovician to Upper Cambrian?) at surface, covers < 0.1 % of this area
Jutland Klippe Sequence, undifferentiated - Rocks of the Jutland klippe sequence occur in six isolated fragments of the Jutland klippe east of Jutland and two fragments of the Peapack klippe along the Peapack-Ralston fault in the New Jersey Highlands hinterland. The sequence is largely varicolored shale and sandstone, but contains lesser amounts of limestone, dolomite and pebble conglomerate. Lash and Drake (1984) correlate this sequence with the accretionary prism deposits of the Greenwich slice of the Hamburg klippe in eastern Pennsylvania. Rocks of the Jutland klippe sequence were folded and thrust over rocks of the Kittatinny Valley sequence during the Taconic orogeny and then were deformed during the Alleghanian orogeny and again during Mesozoic rifting of eastern North America.
Lithology: shale; sandstone; limestone; dolostone (dolomite); conglomerate
Poxono Island Formation (Upper Silurian) at surface, covers < 0.1 % of this area
Poxono Island Formation (White, 1882) - Greenish-gray, finely crystalline to aphanitic, thin- to medium-bedded, flaggy dolomite containing discontinuous lenses of disseminated, rounded quartz grains. Some local quartz sandstone beds and argillaceous dolomite. Lower contact gradational (Epstein, 1973). Formation poorly exposed; located by drill data. Thickness estimated at 183 m (600 ft) from well data.
Lithology: dolostone (dolomite); sandstone
Bloomsburg Formation (Silurian) at surface, covers < 0.1 % of this area
Bloomsburg Formation - Grayish-red siltstone, shale, and sandstone arranged in fining-upward cycles.
Lithology: siltstone; shale; sandstone
Lockatong Formation - Conglomerate facies (Upper Triassic) at surface, covers < 0.1 % of this area
Lockatong Formation Sandstone and Conglomerate Sandstone facies - Unit Trla interfingers laterally and gradationally with quartz sandstone and conglomerate (Trls) and quartzite conglomerate (Trlcq) near Triassic border fault in southwestern area of map.
Lithology: conglomerate; sandstone
Skunnemunk Conglomerate (Middle Devonian) at surface, covers 0.1 % of this area
Skunnemunk Conglomerate (Darton, 1894) - Grayish-purple to grayish-red, thin- to very thick bedded, locally cross-bedded, polymictic conglomerate and sandstone containing clasts of white vein quartz, red and green quartzite and sandstone, red and gray chert, and red shale; interbedded with medium-gray, thin-bedded sandstone and greenish-gray and grayish-red, mud-cracked shale. Conglomerate and sandstone matrix is primarily hematite and microcrystalline quartz. Conglomerate cobbles range to 16.5 cm (6.5 in) long, and average cobble size increases in upper part of unit. Lower contact conformable and gradational as defined by Kummel and Weller (1902). About 915 m (3,000 ft) thick.
Lithology: conglomerate; sandstone; shale; quartzite; chert
Jutland Klippe Sequence Unit A (lower Middle Ordovician to Upper Cambrian) at surface, covers < 0.1 % of this area
Jutland Klippe Sequence Unit A of Perissoratis and others (1979) - Interbedded red, green, and tan shale, sandstone, and dark-gray, aphanitic to fine-grained limestone, which contains floating quartz-sand grains. Grades downward through interbedded sequence of red, green and brown shale to medium-gray to brown, fine- to coarse-grained sandstone and quartz-pebble conglomerate. Lower beds are dark-gray shale and siltstone containing minor dark-gray, aphanitic to fine-grained, medium-bedded limestone. Lower contact is a fault. Contains graptolites in the span of Anisograptus to Isograptus caduceus of Berry (1968) (Perissoratis and others, 1979) and conodonts of the Cordylodus proavus to Paroistodus proteus faunas of the North Atlantic Realm. Thickness is unknown.
Lithology: shale; sandstone; limestone; conglomerate; siltstone
Wildwood Member of the Kirkwood Formation (middle and lower Miocene, Langhian and Burdigalian) at surface, covers 1 % of this area
Wildwood Member - New member named for a well drilled at Wildwood, Cape May County. Typically consists of a very fossiliferous, micaceous, darkgray clay-silt interbedded with fine- to medium-grained, pale-gray-brown sand in lower half of the member. The upper half of the member is more sandy (mostly fine-grained, micaceous quartz sand), thin-bedded to laminated, commonly interbedded with thin-bedded, gray-brown, micaceous clay; wood fragments are common. The basal contact with the underlying unit is sharp and has considerable relief. A 1-m (3-ft)-thick bed of gravel (1 cm (0.4 in) in maximum diameter) with pieces of quartz and worn shells, commonly occurs along the contact. Thickness of the unit varies widely because of the undulating basal contact. The maximum thickness, 80 m (262 ft), was penetrated in the Wildwood well. At the Island Beach well (290019) at Island Beach State Park, Ocean County, the Wildwood is over 30 m (98 ft) thick. The lower 6 m (20 ft) consists of thick interbeds of fine- to medium-grained, massive to locally thick-bedded, extensively bioturbated, micaceous quartz sand and dark-brown and grayish-brown silty clay. The middle part is mostly massive to finely laminated, dark-gray to gray-brown silt to clay. The upper 6 m (20 ft) consists of fine- to coarse-grained, locally gravelly, thin- to thick-bedded sand interbedded with the clay and silt. The age of the Wildwood was determined from diatoms and strontium-isotope age estimates of mollusk shells. The diatom assemblages in this unit fall within Andrews (1988) ECDZ 2, thus indicating a considerable unconformity between this member and the overlying Belleplain (ECDZ 6). ECDZ 2 is in the Delphineis ovata Zone and contains the characteristic diatoms Coscinodiscus lewisianus, Delphineis lineata, Rhaphidodiscus marylandicus, Rhaphoneis fusiformis, R. margaritata, R. wicomicoensis, Sceptroneis caduceus, S. grandis, and S. hungarica. Strontium-isotope analyses on shells from this interval indicate an age range of 17.4 to 15.5 Ma (Sugarman and others, 1993). The isotopic and paleontologic ages suggest that the Wildwood Member straddles the early-middle Miocene boundary (Langhian-Burdigalian boundary). Pollen from the Wildwood has warm-temperate affinities in the lower part and mixed warm- and cool-temperate affinities in the upper part suggesting an overall cooling of the climate during the time of deposition. Collectively, the Wildwood and Belleplain Members constitute the section that Woolman (1889-1902) assigned to his "great diatom bed".
Lithology: clay or mud; silt; sand
Brunswick Formation (Upper Triassic) at surface, covers < 0.1 % of this area
Brunswick Formation - sandstone, siltstone and mudstone.
Lithology: sandstone; siltstone; mudstone
High Point Member (Upper Ordovician) at surface, covers 0.2 % of this area
High Point Member (Drake, 1991) - Medium-dark-gray, thin-bedded shale, siltstone and fine-grained sandstone, containing turbidite sequences Tbcde to Tcde of Bouma (1962). Interbedded with less abundant, light-yellowish-gray-weathering, medium-gray to medium-dark-gray, medium-grained, medium- to thick-bedded and massive, quartz- and calcareous-cemented quartz sandstone containing rip-ups of medium- to dark-gray shale and siltstone that commonly consist of Bouma (1962) turbidite sequences Tab to Ta. Restricted to northeast section of Martinsburg outcrop belt. Thermally metamorphosed near intrusive bodies. Grades along strike to the southwest into Ramseyburg Member by decrease in average grain size, absence of shale rip-ups, and lack of siliceous cement. Lower contact gradational and placed at base of lowermost thick-bedded graywacke or amalgamated graywacke containing shale rip-ups. Unit assigned to Orthograptus ruedemanni zone to Climacograptus spiniferus zone of Riva (1969, 1974) using graptolites collected by Parris and Cruikshank (1992). Thickness ranges from 0 to 1,370 m (0-4,500 ft).
Lithology: sandstone; shale; siltstone
Onondaga Limestone (Lower to Middle Devonian) at surface, covers < 0.1 % of this area
Onondaga Limestone - Schoharie Formation-shale, limestone; Carlisle Center Siltstone; Esopus Shale.
Lithology: shale; limestone; siltstone
Coeymans Formation, Kalkberg Limestone, Coeymans Limestone, Manlius Limestone, undivided (Lower Devonian) at surface, covers < 0.1 % of this area
Coeymans Formation, Kalkberg Limestone, Coeymans Limestone, Manlius Limestone, undivided - At New York border consists of fine-grained, chert-bearing, argillaceous limestone (Kalkberg Limestone) grading downward through coarse-grained limestone (Coeymans Limestone) into fine-grained limestone (Manlius Limestone). Toward southwest these units grade into fine- to coarse-grained limestone with a marked increase in quartz sand that comprises the Coeymans Formation (Epstein and others, 1967). Total thickness 27 m (90 ft). Coeymans Formation (Epstein and others, 1967) - Medium-light-gray, fine- to coarse-grained calcareous sandstone and medium-gray, fine- to coarse-grained, medium- to thick-bedded, locally irregularly-bedded, argillaceous to arenaceous limestone containing lenses of quartz sand and nodules of black chert. Grades downward into medium-gray, fine-grained, argillaceous and arenaceous limestone containing local beds of fine- to coarse-grained pebbly calcareous sandstone. Local bioherms consisting of light-gray to light-pinkish-gray, coarse-grained to very coarse biogenic limestone are unbedded and have sharp boundaries. Lower contact of unit abrupt. Formation thickness varies from 11 m (35 ft) in northeast to 24 m (80 ft) in southwest. Kalkberg Limestone (Chadwick, 1908) - Medium-gray-weathering, medium-dark-gray, fine-grained, very thin to massively bedded fossiliferous limestone. Grades downward into fine- to medium-grained, thin-bedded, fossiliferous argillaceous limestone containing nodules and lenses of dark-gray chert. Grades to the southwest into calcareous and arenaceous rocks of the upper part of the Coeymans Formation near Wallpack Center. Lower contact placed at base of lowest black chert. Approximately 12 m (40 ft) thick. Coeymans Limestone (Clarke and Schuchert, 1899) - Medium-gray weathering, medium-dark-gray, fine-to-coarse-grained, medium- to massively bedded fossiliferous limestone and local argillaceous limestone lenses. Unit is approximately 9 m (30 ft) thick. Between Duttonville and Millville, grades into biohermal and nonbiohermal facies of medium- to coarse-grained limestone of Coeymans Formation of Epstein and others (1967). Manlius Limestone (Vanuxem, 1840) - Medium-gray weathering, medium-dark- to dark-gray, very fine to fine-grained, unevenly bedded fossiliferous limestone. Some local medium-grained limestone, yellowish-gray shale partings and biostromes. Near Hainesville, unit grades into lower part of Coeymans Formation. Lower contact abrupt and placed at top of uppermost very fine grained argillaceous limestone. Thickness approximately 11 m (35 ft).
Lithology: limestone; sandstone; chert
Marcellus Formation (Devonian) at surface, covers < 0.1 % of this area
Marcellus Formation - Black shale; sparse marine fauna and siderite concretions. Contains local limestone ("Purcell") member. Tioga bentonite included at base in eastern Pennsylvania.
Lithology: black shale; limestone; bentonite
Schoharie Formation (Lower Devonian) at surface, covers < 0.1 % of this area
Schoharie Formation (Vanuxem, 1840) - Yellowish-gray- to locally pale-olive-weathering, medium- to dark-gray, medium- to thick-bedded, calcaeous siltstone and lesser amounts of silty limestone. Locally contains thin ribs or pods of black chert in limestone. Limestone content decreases in lower part of unit. Contains the trace fossil Taonurus, a grazing trail. Lower contact gradational and placed at top of highest massive siltstone below lowest limestone. Thickness approximately 53 m (175 ft).
Lithology: siltstone; limestone; chert
Shiloh Marl Member of the Kirkwood Formation (lower Miocene, Burdigalian) at surface, covers 0.4 % of this area
Shiloh Marl Member - Consists of (1) a lower laminated, micaceous, locally fossiliferous (typically thin-walled, small mollusks), dark-gray clay interbedded with very fine grained sand and (2) an upper medium- to coarse-grained, gravelly, massive, pale-brown to medium-gray sand with scattered thin-walled mollusks. Thin, dark-gray clay layers interbedded with thin layers of lignite are common in this upper interval. Like the Wildwood, this unit occurs mainly within the southern sheet and the southeastern part of the central sheet. Thicknesses vary within the basin but are a maximum of 55 m (180 ft). In the Island Beach corehole the unit is clayey at the base and sandy at the top. The basal contact with the underlying unit is sharp but there is little reworked debris along this contact. In detail, the lowest 4.5 m (15 ft) of the unit is a fine- to medium-grained, massive, micaceous, extensively bioturbated, somewhat clayey, quartz sand. Small wood fragments are common. This basal sand bed grades upward into a sequence of horizontally bedded, light- to dark-gray clay and very fine grained, somewhat micaceous quartz sand. Color banding in this interval is strong. A very coarse grained, pale-gray quartz sand with some granules is interbedded with this dominantly clayey sequence. The clayey sequence is overlain by a medium-grained, massive, bioturbated, medium-gray sand similar to the basal sand. This sand grades into a thin- to thick-bedded and crossbedded sequence of dark-gray and brown sand that increases in grain size from coarse to very coarse grained up section. Most of the sand is quartz with lesser amounts of potassium feldspar (6 to 16 percent of the sand fraction). Near the top of the unit, quartz gravel is a common constituent in the very coarse grained sand bed. The age of the Shiloh is early Miocene (Burdigalian) as determined from diatoms. The Shiloh contains Actinoptychus heliopelta (ECDZ 1 of Andrews, 1987, 1988). Strontium age determinations on shells from this unit yielded ages of 20.9 to 19.7 Ma confirming the early Burdigalian age. Pollen studies indicate that the Shiloh has unusually high concentrations of Fagus (beech). Other pollen includes Quercus (oak), Carya (hickory), Pinus (pine), and Ulmus (elm) along with exotics. Overall the assemblage, except possibly for the high concentration of Fagus, indicates a warm-temperate climate during the time of deposition.
Lithology: clay or mud; sand; gravel; lignite
Metabasalt (Late Proterozoic) at surface, covers < 0.1 % of this area
Metabasalt - Sequence of conformably layered volcanic rocks of fine-grained to aphanitic, greenish-gray, retrogressively metamorphosed greenstone, greenschist, and basalt. Greenschist contains clots and lenses of blue quartz and abundant sulfide. Unit does not crop out and is known only from subsurface borings and artificial exposures. Interpreted to be Late Proterozoic by Volkert and Drake (1993) on the basis of geochemical similarity to Late Proterozoic metadiabase dikes in New Jersey Highlands.
Lithology: greenstone; greenschist; meta-basalt
Port Ewen Shale (Lower Devonian) at surface, covers < 0.1 % of this area
Port Ewen Shale (Clarke, 1903) - Upper part is medium-gray- weathering, dark-to- medium-dark-gray, thin- to medium-bedded, fossiliferous, calcareous siltstone and shale. Lower part is medium-dark-gray, irregularly bedded nonfossiliferous, calcareous silty shale. Lower contact abrupt and placed at top of uppermost medium-gray, argillaceous limestone in Minisink Limestone. Thickness approximately 46 m (150 ft).
Lithology: shale; siltstone
Marcellus Shale (Middle Devonian) at surface, covers < 0.1 % of this area
Marcellus Shale (Vanuxem, 1840) - Medium-gray weathering, dark-gray to grayish-black, thin- to thick-bedded, fossiliferous, fissile and limonite-stained locally arenaceous shale. Lower contact grades downward over 12 m (40 ft) from black shale through limy shale, into silty limestone of the Buttermilk Falls Limestone (documented in drill core data of Fletcher and Woodrow, 1970). Approximately 274 m (900 ft) thick.
Lithology: black shale; shale; siltstone; sandstone
Epler Formation (Ordovician) at surface, covers < 0.1 % of this area
Epler Formation - Very finely crystalline, light-gray limestone interbedded with gray dolomite; coarsely crystalline limestone lenses present.
Lithology: limestone; dolostone (dolomite)
Brunswick Formation (Upper Triassic) at surface, covers < 0.1 % of this area
Brunswick Formation - sandstone and conglomerate.
Lithology: sandstone; conglomerate
Wissahickon Formation (Lower Cambrian and Late Proterozoic) at surface, covers < 0.1 % of this area
Wissahickon Formation - Fine- to medium-grained biotite-quartz-plagioclase schist and gneiss that contains thin amphibolite layers. Schist and gneiss in alternating layers suggest a turbidite sequence of shale and graywacke. The rocks are at high metamorphic grade, and, in places, the more pelitic parts have partly melted forming veins of migmatite. Some exposures show evidence of polymetamorphism as micaceous minerals occur both within the schistosity and as static porphyroblasts.
Lithology: schist; gneiss; amphibolite; migmatite
Decker Formation through Poxono Island Formation, undivided (Silurian) at surface, covers < 0.1 % of this area
Decker Formation through Poxono Island Formation, undivided -In descending order: Decker Formation--gray calcareous sandstone having lenses of calcareous conglomerate, siltstone, and shale, and lenses of limestone and dolomite (in Stroudsburg area, includes calcareous shale, limestone, and dolomite of Rondout Formation at top); Bossardville Limestone--gray argillaceous limestone and dolomitic limestone; Poxono Island Formation--thin-bedded dolomite, limestone, and shale; red shale in lower part. This undivided succession is equivalent to Keyser, Tonoloway, and Wills Creek (part) Formations of central Pennsylvania.
Lithology: dolostone (dolomite); limestone; siltstone; shale; sandstone; conglomerate
Gneiss granofels and Migmatite (Middle Proterozoic) at surface, covers < 0.1 % of this area
Gneiss granofels and Migmatite - Gneiss and granofels range in composition from felsic to intermediate to mafic; intermediate compositions predominate. Contains a wide variety of rock types including graphitic schist and marble. Many rocks were injected by a granitoid that has blue quartz and augen of potassic feldspar and are arteritic migmatites. One body of gneiss contains a 1 m by 0.5 m (3 by 2 ft) phacoid of gabbro that is interpreted to be an olistolith. Unit probably represents a sequence of meta-sedimentary and metavolcanic rocks that have been heavily injected and migmatized by felsic magma.
Lithology: gneiss; granofels; schist; marble; migmatite
Interlayered amphibolite and granitic, charnockitic, mangeritic, or syenitic gneiss (Middle Proterozoic) at surface, covers < 0.1 % of this area
Interlayered amphibolite and granitic, charnockitic, mangeritic, or syenitic gneiss.
Lithology: amphibolite; gneiss
Hammer Creek Formation (Upper Triassic) at surface, covers < 0.1 % of this area
Hammer Creek Formation - conglomerate.
Lithology: conglomerate
Esopus Formation (Lower Devonian) at surface, covers < 0.1 % of this area
Esopus Formation (Vanuxem, 1842) - Medium-gray weathering, medium- to dark-gray, laminated to medium-bedded, partly massive, shaly to finely arenaceous siltstone, containing minor calcareous siltstone near top, locally limonite stained. Contains Taonurus. Rocks are cleaved in southwest and extreme northeast part of outcrop belt but not in central region. Lower contact sharp and unconformable where underlying Oriskany Group is coarse quartz sandstone. Elsewhere, lower contact conformable; fine sandstone to siltstone grades downward several meters into silty limestone. Thickness approximately 91 m (300 ft).
Lithology: siltstone
Shawangunk Formation (Silurian) at surface, covers < 0.1 % of this area
Shawangunk Formation - Light- to dark-gray, fine- to very coarse grained sandstone and conglomerate containing thin shale interbeds. Includes four members, in descending order: Tammany--conglomerate and sandstone; Lizard Creek--sandstone and red or green shale; Minsi--sandstone and conglomerate; Weiders--conglomerate. Tammany and Lizard Creek Members together are approximately equivalent to Clinton Group to the west; Minsi and Weiders Members together are equivalent to Tuscarora Formation to the west.
Lithology: sandstone; conglomerate; shale
Helderberg Group (Lower Devonian) at surface, covers < 0.1 % of this area
Helderberg Group - West of Albany: Alsen, Becraft, New Scotland, Kalkberg, Coeymans, and Manlius Limestones; Rondout Dolostone. South of Albany: Port Ewen, Alsen thru Manlius Limestones; Rondout Dolostone.
Lithology: limestone; dolostone (dolomite)

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