On most gamma-ray logs through this contact, there is a sharp gamma high reflecting the concentration of phosphatic sediment. The Potomac Formation crops out only in the Delaware River valley where the river and its tributaries have eroded away the overlying formations. farm Skaneateles Formation - In west: Levanna Shale and Stafford Limestone Members; In east: Butternut, Pompey, and Delphi Station Shale Members, Mottville Sandstone Member. Simpson and lower units are covered. Local thin, pebbly zones with large fossil impressions occur in the middle of the formation. 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. Wachapreague Formation - Coarsening-upward sequence from lower muddy fine-grained sand to upper medium- to coarse-grained gravelly sand, at altitudes from sea level to about 15 ft. (top of unit). Mostly slate, quartzite, hornfels, chert, phyllite, mylonite, schist, gneiss, and minor marble. Locally, the sand has very small amounts of glauconite which may indicate some local marine influence during sedimentation. Copper sulfides and native copper occur locally near base. Composite thicknessof all Upper Wisconsin till may be up to 300 ft (91 m). Conc. Passaic Formation Limestone-clast Conglomerate facies - Limestone conglomerate unit (JTrpcl) is medium-bedded to massive, pebble to boulder conglomerate. Woodbridge Clay Member - Silt, clayey, dark-gray; weathers to red brown or white, locally interbedded with light-gray, clayey, fine- to very fine grained sand (primarily quartz and mica with little feldspar). Thickness 160-225 ft (49-69 m). At the base of the formation in southeast AL is a gravelly medium to coarse sand containing clay pebbles. (0-10 ka), Unconsolidated deposits associated with modern fluvial systems. The maximum thickness, 80 m (262 ft), was penetrated in the Wildwood well. Middendorf Formation - sand, sandstone, and mudstone, gray to pale gray with an orange cast, mottled; clay balls and iron-cemented concretions common, beds laterally discontinuous, cross-bedding common. The Mill River is a basal limestone conglomerate. Alluvial Deposits - Sand, silt, clay, and gravel. Grayish-red, grayish-purple, and dark-brownish-red sequences (Trlr) common in upper half. Upper beds are more sandy than lower beds but also contain many thin to thick beds of clay. GALLATIN LIMESTONE--Blue-gray and yellow mottled hard dense limestone. Manasquan Formation - Clay to clay-silt, massive to finely laminated, green to gray-green, extensively bioturbated. One or more Ordovician Fms (Fremont Limestone, Harding Sandstone, and Manitou Dolomite), Dotsero Fm, Peerless Fm, and Sawatch Quartzite in west-ce, Hawthorn Group, Arcadia Formation, Tampa Member, Hawthorn Group, Coosawhatchie Formation, Charlton Member, Hawthorn Group, Peace River Formation, Bone Valley Member, Lower Tertiary-Cretaceous undifferentiated, Clay, silt, sand, and gravel; Late Pleistocene glacial-lake sediments; Basin and Range province, Dolostone, limestone, sandstone, shale, and conglomerate; Devonian marine continental-shelf deposits; east-central and southeastern Idaho, Gravel and sand; Middle Pleistocene alluvial pediment gravel, Gravel; Early Pleistocene alluvium; western Snake River Plain, Gravel, sand, and clay; Quaternary-Tertiary colluvium and fanglomerate; western Idaho, Gravel, sand, silt, clay; Late Pleistocene glacio-alluvial and lacustrine deposits; Basin and Range, and Snake River Plain, Limestone, shale, siltstone, chert, and conglomerate; Mississippian western turbiditic flysch to eastern shallow-water carbonates; east-central Idaho, Sandstone, limestone, and shale; Upper Triassic marine to non-marine epicontinental deposits; southeastern Idaho, Shale, conglomerate, sandstone, siltstone, limestone, and chert; Mississippian turbidite flysch from a western source; central Idaho, Shale, limestone, and sandstone; Triassic marine to non-marine epicontinental deposits (subunits are TRl and TRu), Silt, clay, and diatomite; Middle Pleistocene lacustrine sediments of lava-dammed lakes; western Snake River Plain, Silt, clay, sand, and gravel; Quaternary-Tertiary alluvial and lacustrine deposits; western Snake River Plain, Siltstone, evaporites, and redbeds; Late Jurassic Cordilleran retroarc-foreland-basin deposits; southeastern Idaho, Siltstone, shale, sandstone, and limestone; Jurassic Cordilleran retroarc-foreland-basin deposits (subunits are Jl and Ju); southeastern Idaho, Lower Chesterian (Glen Dean - Renault) Series, Continental deposits and loess, undifferentiated, Pennington Formation and Newman Limestone, Ste. Bloomsburg and Mifflintown Formations, undivided - Includes, in descending order, the Bloomsburg Formation (Sb) and the Mifflintown Formation--interbedded dark-gray shale and medium-gray fossiliferous limestone; equivalent to "McKenzie" and "Rochester" of earlier workers; not present east of Harrisburg. A laboratory is maintained and tests are constantly made of water for its purity. This section consists of fossiliferous sands and carbonates. Found in subsurface only. The identification of these units is problematic unless the significant molluscan species are recognized. Also see Coarse Aggregate Producers. Only sand from Plant #1 is approved for NJDOT use. The formation thins eastward. FORT SMITH- Mississisippian, Devonian, Silurian, and Ordovician Rocks, Undifferentiated Mississippian and Devonian. Clasts are subangular dolomitic limestone in matrix of brownish- to purplish-red sandstone to mudstone; matrix weathers light-gray to white near faults. Conasauga Shale - Shale with minor limestone and sandstone.

Lithologies are typical of the shallow subsurface. Mainly restricted to northeastern AL and part of the Sequatchie anticline. Peerless Fm: sandstone and dolomite. Unit is characterized by commercial kaolin bodies in older strata from westernmost South Carolina to central Georgia. The presence of these fossil "ghosts" and trace fossils documents marine influence on deposition of the Cypresshead sediments. brown lignitic clays, silts and sands; some sideritic glauconite may weather to brown ironstone in lower part. Original fossil material is not present in the sediments although poorly preserved molds and casts of mollusks and burrow structures are occasionally present. In eastern AL thin to thick-bedded accumulations of the fossil oyster Ostrea cretacea Morton occur throughout much of the formation. Terrace Deposits - Poorly sorted clay, sand, and rounded pebbles and cobbles, deeply weathered. Penholoway Formation: Similar to Cape May, broad lateral extent underlying terraces in the Carolinas; swamps and ridges on terrace surface were originally barrier islands and back bays. Protoliths include basalt, andesite, dacite, and rhyolite deposited as lava or tuff, related sedimentary rock, and shallow intrusive rock. Sand, silt and clay may be present in limited quantities. The Amboy Stoneware is disconformable on the underlying sand. Surficial Deposits, Undivided - sand, clay, gravel, and peat deposited in marine, fluvial, eolian, and lacustrine environments. Mt. Locally, small burrows are present. Sand dunes are common in many places. Gradational southward and eastward into Chickasha Formation. grass elephant tropical grasslands weebly Undifferentiated Hamilton Group - shale, siltstone. Potassium-argon ages on middle and lower parts of sequence range from about 43 to 46 Ma (Magill and others, 1981): one potassium-argon age from dacite near top of sequence is about 40 Ma (see Wells and others, 1983), Moderately well indurated lacustrine and fluvial (flood-plain) deposits of tuff, pumicite, palagonite tuff, and lesser siltstone, arkosic sandstone, and pebble and cobble conglomerate. Thickness up to 180 ft (55 m). Thickness 1,000 to 1,500 feet; Hesse Sandstone - White, vitreous quartzite, medium- to coarse-grained, occurs in massive ledges; Helenmode Member at top is gray to greenish sandstone and shale. Locally the upper part of the unit is Pliocene in age. Informal unit described from a corehole at the Cape May Airport. Potomac Formation - Variegated silts and clays with beds of quartz sand. Lockatong Formation (Kummel, 1897) - Cyclically-deposited sequences consisting of light- to dark-gray, greenish-gray, and black, dolomitic or analcime-bearing silty argillite, laminated mudstone, silty to calcareous, argillaceous, very-fine-grained pyritic sandstone and siltstone, and minor silty limestone (Trl). The Middlebury, which is east of Champlain and Orwell thrusts, and the Youngman, which is east of Highgate Springs thrust, are, due partly to deformation, more slaty in appearance than the Chazy, which is west of the major thrusts. Vicksburg group and Chickasawhay limestone - Chickasawhay limestone, sandy limestone, and sand, present only in eastern MS (mapped with it is the overlying Paynes Hammock sand of Miocene age); Vicksburg group, predominantly limestone and marl, but contains some bentonite and near the top, chocolate-colored clay and some sand. Chadron Formation: Light-colored sand with quartzite and porphyry pebbles, overlain by dark clay; river and lake sediment; as thick as 30 meters (100 feet). Crystal River Formation - white to yellowish-grey medium-grained to coquinoid limestone that is soft and chalky to compact and brittle; principally in southeastern AL but interfingers westward with members of the Yazoo Clay. The Hornerstown is 1.5 to 7 m (5-23 ft) thick. Brule Formation: Pinkish siltstone, clay, and sand; river and lake sediment; as thick as 50 meters (150 feet). Mascot Dolomite - Light-gray, fine-grained, well-bedded cherty dolomite; mottled (red and green) dolomite characteristic; interbeds of bluish-gray limestone in upper part; chert-matrix quartz sandstone at base. Approximately 274 m (900 ft) thick. Thickness up to 180 ft (55 m). Material is a crushed and washed stone sand. JEFFERSON FORMATION--Fetid brown dolomite and limestone. 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). 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. Devonian(?) In the southern sheet, the lower clay facies is exposed only where the Coastal Plain was deeply entrenched and stripped away. Bloomsburg Formation - Grayish-red and greenish-gray shale, siltstone, and very fine to coarse-grained sandstone; some calcareous mudstone in central Pennsylvania; thins to west and is replaced by Mifflintown beds; thickens eastward, replacing overlying Wills Creek and Tonoloway Formations and underlying Mifflintown Formation. The middle part is mostly massive to finely laminated, dark-gray to gray-brown silt to clay.

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. Superimposed on these landforms are swarms of Carolina bays. gray mixed with brown-to-red clay and silty clay; some sand and gravel locally. 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. Lower Tertiary-Cretaceous undifferentiated, as mapped includes Middendorf Formation (Sloan, 1904); "Channel Sands" (LaMoreaux, 1946); Tuscaloosa Formation (Cooke, 1939); and "Huber beds" (Buie, informal terminology), Mississippian undifferentiated: Includes Pennington Shale, Bangor Limestone (except in Floyd County), Hartselle Sandstone, Golconda Formation, Gasper Limestone, Ste. The clay is pervaded by reddish-brown siderite. Typically about 8 m (25 ft) thick. PHOSPHORIA FORMATION AND RELATED ROCKS--Thrust Belt: Upper part is dark- to light-gray chert and shale with black shale and phosphorite at top; lower part is black shale, phosphorite, and cherty dolomite; north Wyoming: Brown sandstone and dolomite, cherty phosphatic and glauconitic dolomite, phosphatic sandstone and dolomite, and greenish-gray to black shale. About 25 feet above the base is a white to light-gray dolomite ("Day Creek Bed") not mapped. The "Chickasha Formation" (Pc) is a deltaic tongue of red-brown to greenish-gray to orange-brown cross-bedded mudstone conglomerate, siltstone, shale, and fine-grained sandstone, about 30 feet thick, in the middle of the Flowerpot Shale, pinching out northward. Erosional unconformity at top. Farther basinward, the bulk of the formation is an unfossiliferous, gray-green to locally tan clayey silt or silty clay. In a few exposures, a thin layer of medium- to coarse-grained quartz sand separates the Hornerstown from the underlying unit. Hamburg has a population of over 800,000. New Oxford conglomerate - Quartz or quartzite pebbles, cobbles, and rare boulders set in a red, sandy, ferruginous matrix; some silica cement; some feldspar clasts. (0-4 Ma), Highly faulted and folded rocks of units Jv, J_, and Pz, deformed and metamorphosed in Jurassic, Cretaceous and Tertiary time. Thickness about 1,200 feet. These deposits are generally light gray or tan. Locally include silt and fine sand and clay as levees on tidal channels. Manasquan Formation - Consists of several lithologies. The interbedded sequence, the major facies in the north, ranges to about 4.5 m (15 ft) thick. Thickness of uppermost Pre-Illinoian till may be up to 120 ft (37 m). Unit is approximately 7.5 m (25 ft) thick, but pinches out along strike. Includes older alluvium and related deposits of Piper (1942), Willamette Silt (Allison, 1953; Wells and Peck, 1961), alluvial silt, sand, and gravel that form terrace deposits of Wells and others (1983), and Gresham and Estacada Formations of Trimble (1963).