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Mineral Resources On-Line Spatial Data

Geologic units containing gravel

Earth material > Unconsolidated material
Gravel
A loose accumulation of rock fragments composed predominantly of more or less rounded pebbles and small stones
Subtopics:
(none)

Alabama - Arkansas - Arizona - California - Colorado - Delaware - Florida - Georgia - Idaho - Illinois - Kansas - Kentucky - Louisiana - Massachusetts - Maryland - Missouri - Mississippi - North Carolina - North Dakota - Nebraska - New Jersey - New Mexico - Nevada - New York - Oklahoma - Oregon - Pennsylvania - South Carolina - South Dakota - Tennessee - Texas - Utah - Virginia - Washington - Wyoming
Alabama
Citronelle Formation (Pleistocene-Pliocene)
Citronelle Formation - moderate-reddish-brown deeply weathered fine to very coarse quartz sand and varicolored typically mottled lenticular beds of clay and clayey gravel. Limonite pebbles and lenses of limonite cemented sand occur locally in weathered exposures. Gravel is composed of chert and quartz pebbles.
Claiborne Group; Tallahatta Formation (Eocene)
Tallahatta Formation - (Claiborne group), White to very light-greenish-gray thin-bedded to massive siliceous claystone; interbedded with thin layers of fossiliferous clay, sandy clay, and glauconitic sand and sandstone. White to light-greenish-gray fine to coarse sand and fine gravel occur at the base of the formation in southwest Alabama (Meridian Sand Member).
Miocene Series undifferentiated (Miocene)
Miocene Series undifferentiated - Moderate-yellowish-orange thin-bedded to massive fine to coarse sand, gravelly sand, thin-bedded to massive clay and sandy clay. Clays are plastic in part. Limonite pellets occur in places along clay-sand contacts. Gravel is composed of quartz and chert granules and pebbles. Locally the upper part of the unit is Pliocene in age.
Tuscaloosa Group; Coker Formation (Cretaceous)
Coker Formation - (Tuscaloosa Group), Light-colored micaceous very fine to medium sand, cross-bedded sand, varicolored micaceous clay, and a few thin gravel beds containing quartz and chert pebbles. Beds of thinly laminated finely glauconitic very fine to fine sand, silt and dark-gray carbonaceous clay (Eoline Member) occur locally in the lower part in western AL. Locally quartz and chert gravels at the base of the formation range in size from very fine pebbles to large cobbles. In southeastern Elmore County the formation includes marine sediments consisting of glauconitic, fossiliferous, quartzose fine to medium sand and medium-gray carbonaceous silty clay. Not mapped east of the Tallapoosa River.
Tuscaloosa Group; Gordo Formation (Cretaceous)
Gordo Formation - (Tuscaloosa Group), Massive beds of cross-bedded sand, gravelly sand, and lenticular beds of locally carbonaceous partly mottled moderate-red and pale-red-purple clay; lower part is predominantly a gravelly sand consisting chiefly of chert and quartz pebbles. Not mapped east of the Tallapooza River.
Tuscaloosa Group undifferentiated (Cretaceous)
Tuscaloosa Group undifferentiated - Light-gray to moderate-reddish-orange clayey, gravelly fine to very coarse sand; massive mottled sandy clay; local wood and leaf beds; and thin beds of indurated sandstone. Gravel consists mainly of quartz and quartzite and range in size from very fine pebbles to large cobbles. Mapped eats of the Tallapoosa River.
Wilcox Group; Nanafalia Formation (Paleocene)
Nanafalia Formation - (Wilcox Group), Members of the Nanafalia Formation follow in descending order. Grampian Hills Member - medium-gray massive clay, claystone, sandy fossiliferous clay, and fossiliferous fine sand. "Ostrea thirsae beds" - glauconitic, abundantly fossiliferous, quartzose fine to medium sand. Gravel Creek Sand Member - pale-yellowish-orange to moderate-reddish-brown micaceous cross-bedded fine to very coarse sand containing gravel and clay pebbles in some exposures. Gravel Creek Member is absent locally and near the base may contain thin beds of lignite. Updip deposits in northern Henry County and southern Barbour County include beds of alternating medium-gray and white clay, carbonaceous clay, white and grayish-yellow fine to coarse sand and lenses of bauxite and bauxitic clay. Sand beds commonly are cross-bedded, gravelly, and contain numerous clay pebbles. The sequence of beds is often obscured by weathering and the collapse of beds into sinkholes in the underlying Clayton Formation.
Wilcox Group; Tuscahoma Sand (Paleocene)
Tuscahoma Sand - (Wilcox Group), Light-gray to light-olive-gray laminated and thin-bedded carbonaceous silt and clay interbedded with fine sand; thin lignite beds occur locally. Lower part of the formation includes beds of fossiliferous, glauconitic fine quartz sand containing speroidal sandstone concretions, gravel and clay pebbles.
Arkansas
Gravel (Phanerozoic | Cenozoic | Tertiary)
Gravel - Gravel on isolated hills within 40 miles (64km) of the Mississippi Embayment. Many small deposits to the west not shown
Sand and gravel (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Early)
Sand and gravel
Silt and sand (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Early)
Silt and sand - Contains lenses of gravel and clay
Wilcox Group (Phanerozoic | Cenozoic | Tertiary | Eocene-Early)
Wilcox Group
Woodbine Formation (Phanerozoic | Mesozoic | Cretaceous-Late)
Woodbine Formation
Arizona
Early Pleistocene to late Miocene basin deposits (Late Pliocene to Early Pleistocene)
Poorly sorted, variably consolidated gravel and sand that range widely in age. These sediments are generally light gray or tan. This unit is generally mapped in areas of deep late Cenozoic stream incision and landscape degradation where thin Quaternary deposits (map units Qy, Qm, Qo) discontinuously blanket older deposits (map units Tsy or Tsm) and the two cannot be differentiated at the scale of this map. (0.75-10 Ma)
Early Pleistocene to latest Pliocene surficial deposits (Late Pliocene to Early Pleistocene)
Coarse relict alluvial fan deposits that form rounded ridges or flat, isolated surfaces that are moderately to deeply incised by streams. These deposits are generally topographically high and have undergone substantial erosion. Deposits are moderately to strongly consolidated, and commonly contain coarser grained sediment than younger deposits in the same area. (0.75-3 Ma)
Holocene river alluvium (Holocene)
Unconsolidated to weakly consolidated sand and gravel in river channels and sand, silt, and clay on floodplains. Also includes young terrace deposits fringing floodplains. (0-10 ka)
Holocene surficial deposits (Holocene)
Unconsolidated deposits associated with modern fluvial systems. This unit consists primarily of fine-grained, well-sorted sediment on alluvial plains, but also includes gravelly channel, terrace, and alluvial fan deposits on middle and upper piedmonts. (0-10 ka)
Late and middle Pleistocene surficial deposits (Middle to Late Pleistocene)
Unconsolidated to weakly consolidated alluvial fan, terrace, and basin-floor deposits with moderate to strong soil development. Fan and terrace deposits are primarily poorly sorted, moderately bedded gravel and sand, and basin-floor deposits are primarily sand, silt, and clay. (10-750 ka)
Pliocene to middle Miocene deposits (Middle Miocene to Pliocene)
Moderately to strongly consolidated conglomerate and sandstone deposited in basins during and after late Tertiary faulting. Includes lesser amounts of mudstone, siltstone, limestone, and gypsum. These deposits are generally light gray or tan. They commonly form high rounded hills and ridges in modern basins, and locally form prominent bluffs. Deposits of this unit are widely exposed in the dissected basins of southeastern and central Arizona. (2-16 Ma)
Quaternary surficial deposits, undivided (Quaternary)
Unconsolidated to strongly consolidated alluvial and eolian deposits. This unit includes: coarse, poorly sorted alluvial fan and terrace deposits on middle and upper piedmonts and along large drainages; sand, silt and clay on alluvial plains and playas; and wind-blown sand deposits. (0-2 Ma)
California
Oigocene nonmarine rocks (?), unit 1 (Klamath Mountains) (Oligocene(?) to Pleistocene(?))
Colorado
Bouldery gravel on old erosion surfaces in Front Range and Never Summer Mountains (Phanerozoic | Cenozoic | Tertiary)
Gravels and alluviums (Phanerozoic | Cenozoic | Quaternary)
Includes Broadway and Louviers Alluviums
Older gravels and alluviums (Phanerozoic | Cenozoic | Quaternary)
Includes Slocum, Verdos, Rocky Flats, and Nussbaum Alluviums in east, and Florida, Bridgetimber, and Bayfield Gravels in southwest
Delaware
Bryn Mawr Formation (?)
Bryn Mawr Formation - Red and brown quartz sand with silt, clay and fine gravel.
Columbia Formation (Pleistocene)
Columbia Formation - Yellow and reddish brown quartz sand with gravel and little clay
Florida
Alluvium (Pleistocene/Holocene)
Alluvium - Undifferentiated Quaternary Sediments - Much of Florida's surface is covered by a varying thickness of undifferentiated sediments consisting of siliciclastics, organics and freshwater carbonates. Where these sediments exceed 20 feet (6.1 meters) thick, they were mapped as discrete units. In an effort to subdivide the undifferentiated sediments, those sediments occurring in flood plains were mapped as alluvial and flood plain deposits (Qal). Sediments showing surficial expression of beach ridges and dunes were mapped separately (Qbd) as were the sediments composing Trail Ridge (Qtr). Terrace sands were not mapped (refer to Healy [1975] for a discussion of the terraces in Florida). The subdivisions of the Undifferentiated Quaternary Sediments (Qu) are not lithostratigraphic units but are utilized in order to facilitate a better understanding of the State's geology. The siliciclastics are light gray, tan, brown to black, unconsolidated to poorly consolidated, clean to clayey, silty, unfossiliferous, variably organic-bearing sands to blue green to olive green, poorly to moderately consolidated, sandy, silty clays. Gravel is occasionally present in the panhandle. Organics occur as plant debris, roots, disseminated organic matrix and beds of peat. Freshwater carbonates, often referred to as marls in the literature, are scattered over much of the State. In southern Florida, freshwater carbonates are nearly ubiquitous in the Everglades. These sediments are buff colored to tan, unconsolidated to poorly consolidated, fossiliferous carbonate muds. Sand, silt and clay may be present in limited quantities. These carbonates often contain organics. The dominant fossils in the freshwater carbonates are mollusks.
Citronelle Formation (Pliocene)
Citronelle Formation - The Citronelle Formation is widespread in the Gulf Coastal Plain. The type section for the Citronelle Formation, named by Matson (1916), is near Citronelle, Alabama. The Citronelle Formation grades laterally, through a broad facies transition, into the Miccosukee Formation of the eastern Florida panhandle. Coe (1979) investigated the Citronelle Formation in portions of the western Florida panhandle. The Citronelle Formation is a siliciclastic, deltaic deposit that is lithologically similar to, and time equivalent with, the Cypresshead Formation and, at least in part, the Long Key Formation (Cunningham et al., 1998) of the peninsula. In the western panhandle, some of the sediments mapped as Citronelle Formation may be reworked Citronelle. The lithologies are the same and there are few fossils present to document a possible younger age. The Citronelle Formation consists of gray to orange, often mottled, unconsolidated to poorly consolidated, very fine to very coarse, poorly sorted, clean to clayey sands. It contains significant amounts of clay, silt and gravel which may occur as beds and lenses and may vary considerably over short distances. Limonite nodules and limonite-cemented beds are common. Marine fossils are rare but fossil pollen, plant remains and occasional vertebrates are found. Much of the Citronelle Formation is highly permeable. It forms the Sand and Gravel Aquifer of the surficial aquifer system.
Miccosukee Formation (Pliocene)
Miccosukee Formation - The Miccosukee Formation, named by Hendry and Yon (1967), is a siliciclastic unit with a limited distribution in the eastern panhandle. It occurs in the Tallahassee Hills from central Gadsden County to eastern Madison County, often capping hills. The Miccosukee Formation grades to the west, through a broad facies transition, in central Gadsden County into the Citronelle Formation. The Miccosukee Formation is a prodeltaic deposit. The Miccosukee Formation is composed of grayish orange to grayish red, mottled, poorly to moderately consolidated, interbedded clay, sand and gravel of varying coarseness and admixtures (Hendry and Yon, 1967). The unit is relatively impermeable but is considered a part of the surficial aquifer system (Southeastern Geological Society, 1986).
Reworked Cypresshead sediments (Pliocene/Pleistocene)
Reworked Cypresshead sediments - Undifferentiated reworked Cypresshead Formation- This unit is the result of post depositional reworking of the Cypresshead siliciclastics. The sediments are fine to coarse quartz sands with scattered quartz gravel and varying percentages of clay matrix.
Trail Ridge sands (Pleistocene)
Trail Ridge Sands - Undifferentiated sediments - Undifferentiated Quaternary Sediments - Much of Florida's surface is covered by a varying thickness of undifferentiated sediments consisting of siliciclastics, organics and freshwater carbonates. Where these sediments exceed 20 feet (6.1 meters) thick, they were mapped as discrete units. In an effort to subdivide the undifferentiated sediments, those sediments occurring in flood plains were mapped as alluvial and flood plain deposits (Qal). Sediments showing surficial expression of beach ridges and dunes were mapped separately (Qbd) as were the sediments composing Trail Ridge (Qtr). Terrace sands were not mapped (refer to Healy [1975] for a discussion of the terraces in Florida). The subdivisions of the Undifferentiated Quaternary Sediments (Qu) are not lithostratigraphic units but are utilized in order to facilitate a better understanding of the State's geology. The siliciclastics are light gray, tan, brown to black, unconsolidated to poorly consolidated, clean to clayey, silty, unfossiliferous, variably organic-bearing sands to blue green to olive green, poorly to moderately consolidated, sandy, silty clays. Gravel is occasionally present in the panhandle. Organics occur as plant debris, roots, disseminated organic matrix and beds of peat. Freshwater carbonates, often referred to as marls in the literature, are scattered over much of the State. In southern Florida, freshwater carbonates are nearly ubiquitous in the Everglades. These sediments are buff colored to tan, unconsolidated to poorly consolidated, fossiliferous carbonate muds. Sand, silt and clay may be present in limited quantities. These carbonates often contain organics. The dominant fossils in the freshwater carbonates are mollusks.
Undifferentiated sediments (Pleistocene/Holocene)
Undifferentiated sediments - Undifferentiated Quaternary Sediments - Much of Florida's surface is covered by a varying thickness of undifferentiated sediments consisting of siliciclastics, organics and freshwater carbonates. Where these sediments exceed 20 feet (6.1 meters) thick, they were mapped as discrete units. In an effort to subdivide the undifferentiated sediments, those sediments occurring in flood plains were mapped as alluvial and flood plain deposits (Qal). Sediments showing surficial expression of beach ridges and dunes were mapped separately (Qbd) as were the sediments composing Trail Ridge (Qtr). Terrace sands were not mapped (refer to Healy [1975] for a discussion of the terraces in Florida). The subdivisions of the Undifferentiated Quaternary Sediments (Qu) are not lithostratigraphic units but are utilized in order to facilitate a better understanding of the State's geology. The siliciclastics are light gray, tan, brown to black, unconsolidated to poorly consolidated, clean to clayey, silty, unfossiliferous, variably organic-bearing sands to blue green to olive green, poorly to moderately consolidated, sandy, silty clays. Gravel is occasionally present in the panhandle. Organics occur as plant debris, roots, disseminated organic matrix and beds of peat. Freshwater carbonates, often referred to as marls in the literature, are scattered over much of the State. In southern Florida, freshwater carbonates are nearly ubiquitous in the Everglades. These sediments are buff colored to tan, unconsolidated to poorly consolidated, fossiliferous carbonate muds. Sand, silt and clay may be present in limited quantities. These carbonates often contain organics. The dominant fossils in the freshwater carbonates are mollusks.
Georgia
Miccosukee Formation (Neogene)
Miccosukee Formation
Pleistocene-Pliocene sands and gravels (Pleistocene-Pliocene)
Pleistocene-Pliocene sands and gravels, includes, in part, Sunderland, Coharie, and Brandywine "Formations" of Cooke, 1939
Tuscaloosa Formation (Cretaceous)
Tuscaloosa Formation
Idaho
Basalt and gravel; Late Pleistocene basalt flows and interlayered gravel of subunit 2b; Snake River Plain (Late Pleistocene)
Upper Pleistocene Snake Plain basaltic lava flows, unit 2.
Basalt, clay, and gravel; Late Pleistocene basalt flows with interlayered alluvial and lacustrine sediments; Snake River Plain and vicinity (subunits are Qpu1b, Qpu2b, Qpu3b, and Qpu4b) (Late Pleistocene)
Upper Pleistocene Snake Plain lava flows; local stratigraphic position shown by (Qpu4b, Qpu3b, Qpu2b, Qpu1b).
Basalt, gravel, and pumice; Late Pleistocene basaltic volcanics and interlayered sedimetnsof subunit 3b; Snake River Plain (Late Pleistocene)
Upper Pleistocene Snake Plain basaltic lava flows, unit 3.
Clay, silt, sand, and gravel; Late Pleistocene glacial-lake sediments; Basin and Range province (Late Pleistocene)
Pleistocene glacial-lake, ponded-water, and shoreline sediments.
Gravel and sand; Middle Pleistocene alluvial pediment gravel (Pleistocene )
Middle Pleistocene deposits; outwash, fanglomerate, flood and terrace gravels.
Gravel; Early Pleistocene alluvium; western Snake River Plain (Pleistocene)
Lower Pleistocene deposits; outwash, fanglomerate, flood and terrace gravels.
Gravel, sand, and clay; Quaternary-Tertiary colluvium and fanglomerate; western Idaho (Pleistocene and Pliocene)
Pleistocene and Pliocene fanglomerate, colluvium, and poorly sorted gravel deposits.
Gravel, sand, silt, clay; Late Pleistocene glacio-alluvial and lacustrine deposits; Basin and Range, and Snake River Plain (Late Pleistocene)
Upper Pleistocene deposits; outwash, fanglomerate, flood and terrace gravels.
Silt, clay, and diatomite; Middle Pleistocene lacustrine sediments of lava-dammed lakes; western Snake River Plain (Middle Pleistocene)
Middle Pleistocene lava-dammed Snake Plain lake beds of silt, clay and diatomite.
Silt, clay, sand, and gravel; Quaternary-Tertiary alluvial and lacustrine deposits; western Snake River Plain (Early Pleistocene and Late Pliocene)
Pleistocene and Pliocene stream and lake deposits.
Illinois
Caseyville Formation (Pennsylvanian)
Caseyville
Cretaceous (Cretaceous)
Cretaceous
Tertiary - Paleocene, Eocene (Tertiary)
Tertiary - Paleocene, Eocene
Kansas
Alluvium (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
unconsolidated sand, silt, clay, and gravel
Alluvium (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
unconsolidated sand, silt, clay, and gravel
Alluvium (Phanerozoic | Cenozoic | Tertiary)
largely chert gravel
Drift (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
sand, silt, clay, and some gravel
Kentucky
Continental deposits and loess, undifferentiated (Tertiary to Quaternary)
Continental deposits and loess, undifferentiated; West of the Tennessee River
Continental deposits, undifferentiated (Tertiary to Quaternary)
Continental deposits, undifferentiated; East of the Tennessee River
Tuscaloosa Formation (Upper Cretaceous)
Tuscaloosa Formation
Louisiana
Alluvium (Phanerozoic | Cenozoic | Quaternary | Holocene)
gray to brownish gray clay and silty clay, reddish brown in the Red River Valley, some sand and gravel locally.
Blounts Creek Member (Phanerozoic | Cenozoic | Tertiary | Miocene Pliocene)
gray to green silty clays, siltstones, and silts with abundant sand beds; some lignite and lenses of black chert gravel.
Braided Stream Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
light gray, tan and brown fine to coarse sand; some clay silt and gravel.
Braided Stream Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
light gray, tan and brown fine to coarse sand; some clay silt and gravel. Overlain by 1-9 meters of loess.
Carnahan Bayou Member (Phanerozoic | Cenozoic | Tertiary | Miocene)
yellow to gray siltstones, sandstones, and clays with thin tuffaceous beds; some lenses of black chert gravel; petrified wood locally.
Deweyville Terrace (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
gray mixed with brown-to-red clay and silty clay; some sand and gravel locally.
High Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
tan to orange clay, silt, and sand with a large amount of basal gravels.
High Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
tan to orange clay, silt, and sand with a large amount of basal gravels. Overlain by 1-9 meters of loess.
Intermediate Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
light gray to orange-brown clay, sandy clay, and silt; much sand and gravel locally. Overlain by 1-9 meters of loess.
Intermediate Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
light gray to orange-brown clay, sandy clay, and silt; much sand and gravel locally.
Prairie Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
light gray to light brown clay, sandy clay, silt, sand, and some gravels. Overlain by 1-9 meters of loess.
Prairie Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
light gray to light brown clay, sandy clay, silt, sand, and some gravels.
Williamson Creek Member (Phanerozoic | Cenozoic | Tertiary | Miocene)
white to gray silts, siltstones, silty clays, and sand beds; some lenses of black chert gravel.
Massachusetts
Cretaceous sediments (Cretaceous)
Cretaceous sediments - Clay, silt, sand, and gravel, mostly of non-marine and nearshore marine origin, Campanian and older.
Maryland
Lowland Deposits (Quaternary)
Lowland Deposits - Gravel, sand, silt, and clay. Medium- to coarse-grained sand and gravel; cobbles and boulders near base; commonly contains reworked Eocene glauconite; varicolored silts and clays; brown to dark gray lignitic silty clay; contains estuarine to marine fauna in some areas (includes in part Pamlico, Talbot, Wicomico and Sunderland Formations of earlier reports); thickness 0 to 150 feet.
Magothy Formation (Cretaceous)
Magothy Formation - Loose, white, cross-bedded, "sugary", lignitic sands and dark gray, laminated silty clays; white to orange-brown, iron-stained, subrounded quartzose gravels in western Anne Arundel County; absent in outcrop southwest of Patuxent River; thickness 0 to 60 feet.
Monmouth Formation (Cretaceous)
Monmouth Formation - Dark gray to reddish-brown, micaceous, glauconitic, argillaceous, fine- to coarse-grained sand; basal gravel in Prince Georges County; thickness 0 to 100 feet.
Potomac Group, including Raritan and Patapsco Formations, Arundel Clay, and Patuxent Formation (Cretaceous)
Potomac Group - Interbedded quartzose gravels; protoquartzitic to orthoquartzitic argillaceous sands; and white, dark gray, and multicolored silts and clays; thickness 0 to 800 feet. Includes Raritan and Patapsco Formations - Gray, brown, and red variegated silts and clays; lenticular, cross-bedded, argillaceous, subrounded sands; minor gravels; thickness 0 to 400 feet; Arundel Clay - Dark gray and maroon lignitic clays; abundant siderite concretions; present only in Baltimore-Washington area; thickness 0 to 100 feet; and Patuxent Formation - White or light gray to orange-brown, moderately sorted, cross-bedded, argillaceous, angular sands and subrounded quartz gravels; silts and clays subordinate, predominantly pale gray; thickness 0 to 250 feet.
Quaternary Deposits Undivided (Quaternary)
Quaternary Deposits Undivided - Undifferentiated gray to buff sand and gravel, gray to brown lignitic silt and clay, occasional boulders, and rare shell beds. Surficial deposits occur as intercalated fluvial sands and marsh muds (e.g. in upstream floodplain of the Wicomico and Nanticoke Rivers), well-sorted, stablized dune sands (e.g. eastern Wicomico County), shell-bearing estuarine clays and silts (e.g. lower Dorchester County) and Pocomoke River basin of Worcester County), and beach zone sands (e.g. Fenwick and Assateague Islands). Wisconsin to Holocene in age. Subsurface deposits of pre-Wisconsin age consist of buff to reddish-brown sand and gravel locally incised into Miocene sediments (e.g. Salisbury area), estuarine to marine white to gray sands, and gray to blue, shell-bearing clays (e.g. Worcester County).
Upland Deposits (Eastern Shore) (Quaternary)
Upland Deposits (Eastern Shore) - Gravel, sand, silt, and clay. Mostly cross-bedded, poorly sorted, medium- to coarse-grained white to red sand and gravel; boulders near base; minor pink and yellow silts and clays; (Wicomico Formation of earlier reports); thickness 0 to 90 feet, locally thicker in paleochannels.
Upland Deposits (Western Shore) (Quaternary)
Upland Deposits (Western Shore) - Gravel and sand, commonly orange-brown, locally limonite-cemented; minor silt and red, white, or gray clay; (includes Brandywine, Bryn Mawr, and Sunderland Formations of earlier reports); lower gravel member and upper loam member in Southern Maryland; thickness 0 to 50 feet.
Missouri
GULFIAN SERIES (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian])
GULFIAN SERIES - Owl Creek Formation - massive, sandy, micaceous, fossilliferous, glauconitic marine clay, max 100 ft. McNairy Formation - unconsolidated sandstone with clay and gravel lenses, max of 250 ft.
HOLOCENE SERIES (Phanerozoic | Cenozoic | Quaternary | Holocene)
HOLOCENE SERIES - Alluvium - clay, silt, sand, and gravel
PLEISTOCENE SERIES (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
PLEISTOCENE SERIES - Loess, till, drift, clay, silt, sand and gravel (shown on cross section, not on map)
TERTIARY SYSTEM (Phanerozoic | Cenozoic | Tertiary | Paleocene Eocene(?) Oligocene(?) Miocene(?) Pliocene-Early(?) Pliocene-Middle(?) Pliocene-Late)
TERTIARY SYSTEM - PLIOCENE SERIES - Mounds Gravel (Lafayette Formation) - ferruginous, chert gravel, max of 60 ft. EOCENE SERIES - Wilcox Group - includes Holly Springs Formation - x - bedded sandstone, clay and gravel, max of 1200 ft.; Ackerman Formation - clay with lens of sand and gravel, max of 100ft. PALEOCENE SERIES - Midway Group - includes Porters Creek Clay - bentonitic clay, max of 200 ft.; Clayton Formation - marl, fossiliferous, calcareous, limonitic, glauconitic sand and clay, max of 20 ft.,
Mississippi
Catahoula formation (Miocene)
Catahoula formation - Irregularly bedded gray sand and sandstone; mottled red and gray, green, and chocolate-colored clay; some quartzite, and some gravel; the Paynes Hammock sand, sandy limestone cross-bedded fine green sand, and thin-bedded sand and clay, is mapped with the underlying Chickasawhay limestone in eastern MS.
Citronelle formation (Pleistocene)
Citronelle formation - Red sand and gravel and white clay; may be of Pliocene age; the formation mapped is equivalent to the Willis sand and does not include the terrace deposits, colluvium, and residuum commonly considered "Citronelle".
Coastal deposits (Holocene)
Coastal deposits - Loam, sand, gravel and clay.
Eutaw formation (Upper Cretaceous)
Eutaw formation - More or less cross-bedded and thinly laminated glauconitic sand and clay; basal part includes the McShan formation, greenish-gray, micaceous, locally very glauconitic, very fine-grained sand and thin-bedded light-gray clay, small chert gravels may be present in basal beds, not recognized in northern Tishomingo County.
Tuscaloosa formation (Upper Cretaceous)
Tuscaloosa formation - Light and vari-colored irregularly bedded sand, clay, and gravel; gravel is mostly in lower portion.
North Carolina
Surficial Deposits, Undivided (Quaternary)
Surficial Deposits, Undivided - sand, clay, gravel, and peat deposited in marine, fluvial, eolian, and lacustrine environments. Quaternary deposits not shown at altitudes greater than approx. 205 feet above mean sea level (Suffolk Scarp, in part).
Terrace Deposits and Upland Sediment (Tertiary)
Terrace Deposits and Upland Sediment - gravel, clayey sand, and sand, minor iron-oxide cemented sandstone.
North Dakota
Coleharbor Formation- River Sediment- Collapsed River Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Moderately well sorted cross-bedded sand and plane-bedded gravel, including sediment of melt-water and other rivers; as thick as 30 meters (100 feet). Faulted and contorted supraglacial sediment with hummocky topography.
Coleharbor Formation- River Sediment- Uncollapsed River Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Moderately well sorted cross-bedded sand and plane-bedded gravel, including sediment of melt-water and other rivers; as thick as 30 meters (100 feet). Flat-bedded sediment of gently sloping plains and terraces, commonly with braided-channel scars.
Coleharbor Formation- Shoreline Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Well-sorted sand and gravel of beach-ridge complexes; as thick as 5 meters (15 feet).
Glacial Sediment- Collapsed/Draped Transition Sediments (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Collapsed Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Collapsed Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Collapsed Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Collapsed Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Glacial Sediment Draped Over Pre-existing Topography (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment-Glacial Sediment Draped Over Pre-existing Topography (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Glacial Sediment on Subglacially Molded Surfaces (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Glacial Sediment on Thrust Masses (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- River-Eroded Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Slopwash-Eroded Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Wave-Eroded Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Quaternary and Upper Tertiary Sediment, Undivided (Phanerozoic | Cenozoic | Tertiary Quaternary | Pliocene Pleistocene(?) Holocene)
Largely river sediment; includes upper Quaternary terrace, fan, and pediment gravel composed of subanglar pebbles and cobbles of locally-derived material such as sandstone, silicified wood, and concretions and Pliocene (?) to middle (?) Quaternary clay, silt, sand, and gravel composed of rounded pebbles and cobbles of quartzite and porphyry derived from the Black Hills or Rocky Mountains; as thick as 100 meters (300 feet)
Nebraska
Dakota Group (Phanerozoic | Mesozoic | Cretaceous-Early)
Upper part is white, light-gray, brownish-gray, yellow, redish-brown, and red sandstone and shale. Sandstone is very fine to coarse grained, friable, micaeous, crossbedded, and lenticular; locally contains gravel near base. contains numerous zones of ironstone and siltstone concretions of variable thickness. Middle part is light-gray, yellow, red brown and dark-gray, sandy carbonaceous shale; commonly contains a zone of concretions near top. Lower part is sandstone similar to that in upper except there are zones of siderite concretions and, locally a basal zone of chert pebbles. Approx. max thickness 600 ft.
New Jersey
Cohansey Formation (Middle Miocene, Serravallian)
Cohansey Formation - Sand, white to yellow with local gravel and clay. Locally stained red or orange brown by iron oxides and (or) cemented into large blocks of ironstone. Unweathered clay is typically dark gray, but commonly weathers white where interbedded with thin beds of ironstone. Unit is a complex of interfingering marine and nonmarine facies. Sand is typically medium grained and moderately sorted although it ranges from fine to very coarse grained and from poorly to well sorted. Sand consists of quartz and siliceous rock fragments. Some beds are locally micaceous, and in the Lakehurst area, Ocean County, some beds have high concentrations of "black" sand (pseudorutile) that was once extensively mined. In general, the sand is crossbedded, although the style of crossbedding varies significantly with the paleoenvironment. Trough crossbedding predominates, especially in the nonmarine channel fill deposits, and the scale of the crossbeds varies from small to large. In some areas, planar bedding is well developed in sections that have abundant marine burrows (mostly the clay-lined trace fossil Ophiomorpha nodosa). Such marine-influenced beds (largely foreshore deposits) occur on the central sheet west of Asbury Park, near Adelphia, Monmouth County, north of the Lakehurst Naval Air Station, Ocean County, and at Juliustown, Burlington County (Owens and Sohl, 1969), and on the southern sheet as far north as Salem, Salem County. Gravel beds occur locally, especially in updip areas such as near New Egypt, Ocean County, in the Atlantic Highlands and in the highlands west of Barnegat, Ocean County, in the southern part of the central sheet and in mixed marine and nonmarine facies in the northeastern part of the southern sheet where gravel occurs in well-defined channels. Most of the gravel is 1.3 to 2.5 cm (0.5-1.0 in) in diameter, but pieces as long as 10 cm (4 in) are present. The gravel is composed of quartz with small amounts of black chert and quartzite. Clay commonly occurs as discrete, thin, discontinuous beds, is dark gray where unweathered, white or red where weathered. Lesser, thin laminated clay strata also are present. Locally, as near Lakehurst, thick, dark-gray, very lignitic clay was uncovered during the mining of ilmenite and is informally called the Legler lignite (Rachele, 1976). An extensive, well-preserved leaf flora was collected from a thick clay lens in a pit near Millville, Cumberland County. The leaf flora was dominated by Alangium sp., a tree no longer growing in eastern North America (J.A. Wolfe, written commun., 1992). Maximum thickness in the map area is about 60 m (197 ft); however, thickness is difficult to determine because of the irregular basal contact and extensive post-depositional erosion. There is as much as 18 m (59 ft) of relief along the basal contact. The basal contact is sharp, undulatory, and directly overlain by a thin gravel bed. The Cohansey Formation unconformably overlies the Kirkwood Formation and is found in channels cut down into the Kirkwood. Where the Kirkwood consists of sandy, light-colored sediments, the basal contact of the Cohansey is drawn below crossbedded sediments. Where the Kirkwood consists of dark-colored silty beds, the basal contact is drawn between light-colored Cohansey sediments and the underlying dark-colored sediments. The Cohansey was markedly thinned because of erosion prior to deposition of overlying units in the western and southern parts of the southern sheet (Owens and Minard, 1975). The unit has been extensively eroded and stripped from large areas of the New Jersey Coastal Plain, particularly in the central sheet where outliers are common. In spite of its widespread nature, the Cohansey is poorly exposed because of its loose sandy composition, which causes it to erode easily (Newell and others, in press). Because of this same sandy nature, the Cohansey has been widely mined for sand, and manmade exposures are common in many areas. The age of the Cohansey is controversial because no calcareous microfauna or macrofauna have been found in this formation. The best indication of age comes from pollen and spores obtained from dark carbonaceous clay. Rachele (1976) analyzed the microflora from the Legler site and noted that the Cohansey had a rich and varied assemblage including several genera labeled "exotics" which no longer occur in the northeastern United States: Engelhardia, Pterocarya, Podocarpus, and Cyathea. Greller and Rachele (1984) estimated a middle Miocene age. Ager's (in Owens and others, 1988) analysis of the Cohansey from a corehole at Mays Landing also suggests a middle Miocene (Serravallian) age.
Magothy Formation (Upper Cretaceous, middle and lower Santonian)
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.
Magothy Formation (Upper Cretaceous, middle and lower Santonian)
Magothy Formation - Sand, quartz, fine- to coarse-grained, locally gravelly (especially at the base), white; weathers yellow brown or orange brown, interbedded with thin-bedded clay or dark-gray clay-silt mainly at the top of the formation. Muscovite and feldspar are minor sand constituents. Large wood fragments occur in many clay layers. Clay weathers to gray brown or white. Formation characterized by local vertical and lateral facies changes. The Magothy is best exposed and thickest (about 80 m (262 ft)) in the Raritan Bay area. The outcrop belt is widest in the north and narrows to the southwest. The formation is about 25 m (82 ft) thick or less in the southern sheet. The formation is poorly exposed because of its sandy nature and its widespread cover by younger sediments. The old geologic map of New Jersey (Lewis and Kummel, 1910-1912, revised 1950) showed the Magothy to consist of only one lithology (Cliffwood beds at Cliffwood Beach, Monmouth County). Subsequent pollen studies of the Magothy and the underlying Raritan Formation showed most of the Raritan to be the same age as the Magothy. Wolfe and Pakiser (1971) redefined and considerably expanded the Magothy. Kummel and Knapp (1904) had already recognized that the Magothy, as used here, contained a large number of lithologies. At the time of their study, the Magothy was extensively mined for clay and sand and was well exposed. Their subdivisions had economic designations (for example, Amboy stoneware clay). Barksdale and others (1943) later gave geographic names to these subdivisions, discussed individually below. The lower contact of the Magothy in the Delaware River valley is difficult to place because the lower part of the Magothy is lithically similar to the underlying Potomac Formation. The contact is placed at the base of the lowest dark-gray clay in the Magothy. The best faunas from the Magothy were obtained from siderite concretions and slabs in and near Cliffwood Beach representing only the top of the formation. These faunas were discussed in detail by Weller (1904, 1907) and supplemented by Sohl (in Owens and others, 1977). The presence of Ostrea cretacea in the Cliffwood Beach fauna suggests that the upper part of the Magothy is late Santonian in age. Wolfe and Pakiser (1971) and Christopher (1979, 1982) discussed the microfloral assemblage in the Magothy. Christopher subdivided the Magothy into three zones: Complexipollis exigua-Santalacites minor (oldest), ?Pseudoplicapollis longiannulata-Plicapollis incisa (middle), and ?Pseudoplicapollis cuneata-Semioculopollis verrucosa (youngest). The oldest zone, originally considered to be as old as Turonian, was subsequently considered to be post-Coniacian Christopher, 1982). The middle and upper zones are also probably Santonian. Christopher (1979) followed the nomenclature for the subdivisions elaborated upon earlier. The Cliffwood and Morgan beds, and, presumably the upper thin-bedded sequence, would include the youngest pollen zone; the Amboy Stoneware Clay Member and perhaps the uppermost part of the Old Bridge Sand Member, the middle pollen zone; and the lower part of the Old Bridge Sand Member and South Amboy Fire Clay Member, the oldest pollen zone. The Magothy is considered herein to be of Santonian age. Cliffwood beds - Typically very sandy, horizontally bedded to crossbedded, mainly small-scale trough crossbeds. Thin layers of dark, fine, carbonaceous matter are interbedded with sand. Carbonaceous units are conspicuously micaceous; the sand is less so. Sand is typically fine to medium grained and locally burrowed. Burrows include the small-diameter Ophiomorpha nodosa and some that are not clay lined. Slabs of dark-reddish-brown siderite were common at the base of the bluff at Cliffwood Beach before the outcrop was covered. Some of these slabs had many fossil molds, typically a large number of pelecypods. Lower in the section, between high and low tide level, there is a pale-gray clay-silt about 1.5 m (5 ft) thick with many small reddish-brown siderite concretions. These concretions have many fossils that were described in detail by Weller (1904). The Cliffwood beds are about 7.5 m (25 ft) thick in outcrop. Equivalents of the Cliffwood beds are exposed near the Delaware River between Trenton and Florence, Burlington County. These beds are mainly sand, as are those at Cliffwood Beach, but they tend to have more crossbedding than the typical Cliffwood strata and no burrows or marine fossils. In addition, beds of quartz gravel are present in the Cliffwood near Riverside, Burlington County. Morgan beds - Occur only in the northern part of the central sheet. They consist of interbedded, thin, dark-colored clay and fine-grained, light-colored, micaceous sand. Clay is locally more abundant in the Morgan than in the Cliffwood beds. Sand ranges from massive to locally crossbedded and locally has fine organic matter. This unit is exposed only in the South Amboy quadrangle where it is as much as 12 m (39 ft) thick. It grades downward into underlying clay. Amboy Stoneware Clay Member - Crops out only in the South Amboy quadrangle in the central sheet and is mainly dark-gray, white-weathering, interbedded clay and silt to fine-grained quartz sand. Clay has abundant, fine, carbonaceous matter and fine mica flakes. Small cylindrical burrows are abundant in this unit. Locally, the clay is interbedded with sand and contains large pieces of lignitized, bored (Teredolites) logs. Large slabs of pyrite-cemented sand are associated with the woody beds. Amber occurs in some of the wood. Unit is approximately 7.5 m (25 ft) thick, but pinches out along strike. The Amboy Stoneware is disconformable on the underlying sand. Old Bridge Sand Member - Predominantly a light-colored sand, extensively crossbedded and locally interbedded with dark-gray laminae; clay is highly carbonaceous, woody, in discontinuous beds, especially near the base. The scale of crossbedding varies from small to large. Locally, small burrows are present. Unit is as much as 12 m (39 ft) thick and rests disconformably on the underlying unit. South Amboy Fire Clay Member - Basal member of the Magothy Formation. Unit resembles the Amboy Stoneware Clay Member, particularly in its lensing character. Unit is best exposed in the central sheet in the South Amboy quadrangle and in the Delaware River valley at the base of the bluffs at Florence. The South Amboy is a dark, massive to finely laminated clay, locally oxidized to white or red. Unit fills large channels and has local concentrations of large, pyrite-encrusted, lignitized logs. Some of the clay is slumped, suggesting post-depositional undercutting during channel migration. The clay is interbedded with fine- to medium-grained, crossbedded sand. The basal contact with the underlying Raritan is well exposed in the Sayre and Fisher Pit in Sayreville, Middlesex County, where the contact is marked by a deeply weathered gravel zone.
Mt. Laurel Formation (Upper Cretaceous, upper Campanian)
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.
Potomac Formation, unit 3 (Upper Cretaceous, lower Cenomanian)
Potomac Formation - Sand, fine- to coarse-grained, locally gravelly, crossbedded, light-colored, interbedded with white or variegated red and yellow, massive clay, and rarely dark-gray, woody clay. The Potomac Formation crops out only in the Delaware River valley where the river and its tributaries have eroded away the overlying formations. The Potomac has been mapped in a broad belt parallel to the inner edge of the Coastal Plain. Although mapped in a broad belt, the Potomac is very poorly exposed because of the widespread cover of surficial sediments. The best exposures occur where surficial material is mined away in the Camden area. Unit is about 45 m (148 ft) thick. Contact with the overlying Magothy Formation is difficult to pick where the basal Magothy also contains variegated clays. Most of the basal Magothy has more dark-colored clay, and the contact was drawn by using this criterion. The basal contact of the Potomac with the underlying crystalline rock is not exposed in New Jersey. Biostratigraphically, the Potomac has been separated into pollen zones I, II, and III (Doyle, 1969; Doyle and Robbins, 1977). Samples from the Potomac Formation in the Camden area and along the Delaware River nearby contain pollen assemblages of early Cenomanian age (Zone III) (Les Sirkin, written commun., 1988).
Shiloh Marl Member of the Kirkwood Formation (lower Miocene, Burdigalian)
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.
Tinton Formation (Upper Cretaceous, upper Maastrichtian)
Tinton Formation - Sand, quartz, and glauconite in varying proportions, very clayey and locally indurated by siderite into hard, massive ledges. Sand is dark gray to dark yellow where unweathered; where weathered, siderite changes color of unit to orange brown because of iron oxides, and the formation is stained or cemented in exotic patterns. The Tinton crops out in the northern part of the central sheet from Sandy Hook, Monmouth County, to the northernmost part of the Roosevelt quadrangle, near Perrineville. Unit unconformably overlies the Red Bank Formation in the high hills of the northern Coastal Plain, most notably near Perrineville and Morganville, Monmouth County. In these updip areas, fine gravel, 1 cm (0.4 in) maximum diameter, or large shell concentrations are found along the basal contact. The typical basal bed is a massive, glauconitic (10-35 percent), fine to medium-grained quartz sand with scattered gravel. The massive character of the basal bed is the result of extensive bioturbation. Burrows, filled with glauconite sand of the Tinton, project down into the quartz sand of the underlying Red Bank Formation. At lower elevations downdip, the Tinton is less weathered, much darker, more glauconitic, and typically indurated. The type locality on Pine Brook at Tinton Falls, Monmouth County, is in this downdip area. At Tinton Falls, 7 to 8 m (23-26 ft) of the Tinton is exposed and has a higher glauconite content than in the updip area. Glauconite at Tinton Falls is light green to pale yellow, and many of the grains have a smooth polished surface that is almost lustrous. Thin sections of the Tinton reveal that many of the grains are oolitic (Owens and Sohl, 1973). X-ray analyses indicate the presence of mixed clay minerals; therefore, the unit is not pure glauconite. The Tinton Formation at Tinton Falls has scattered molds of calcitic fossils and aragonitic shells. Richards (1958) recorded 30 species of mollusks from the Tinton in this area. Of importance are Sphenodiscus lobatus, Cucullaea (Idonearca) littlei, and Scabrotrigonia cerulia. In New Jersey, Scabrotrigonia cerulia is restricted to the Tinton. All three species are common to the upper Maastrichtian Haustator bilira Zone of Sohl (in Owens and others, 1977). Strontium-isotope analysis on calcareous shells from the Tinton yielded ages of 66.2 to 65.6 Ma or a late Maastrichtian age (Sugarman and others, 1995).
Unnamed Formation at Cape May (upper Pliocene)
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.
New Mexico
Los Pinos Formation of Lower Santa Fe Group (Phanerozoic | Cenozoic | Tertiary)
Los Pinos Formation of Lower Santa Fe Group (Miocene and upper Oligocene); includes Carson Conglomerate (Dane and Bachman, 1965) in Tusas Mountains-San Luis Basin area
Nevada
Banbury Formation (Middle Miocene to Late Miocene)
BANBURY FORMATION-Basalt, gravel, and tuffaceous sediments locally. Northeast Humboldt County and northwest Elko County
New York
Monmouth Group, Matawan Group and Magothy Formation (Upper Cretaceous)
Monmouth Group, Matawan Group and Magothy Formation - silty clay, glauconitic sandy clay, sand, gravel.
Raritan Formation (Upper Cretaceous)
Raritan Formation - clay, silty clay, sand, gravel.
Oklahoma
Ogallala Formation (Phanerozoic | Cenozoic | Tertiary | Pliocene)
CIMARRON- Generally semiconsolidated clay, silt, sand, gravel, and caliche 0 to 400 feet thick. BEAVER- Interbedded sand, siltstone, clay, gravel lenses, and thin limestone. Caliche common near surface but occurrence is not limited to the surface. Caliche accounts for most of the white color in the Ogallala. Other colors generally light tan or buff but locally may be pastel shades of almost any color. The Laverne and Rexroad Formations of Pliocene age and the Meade Group and Odee (of local usage) and other formations of Pleistocene age occur locally and are included with the Ogallala Formation, 0-700 feet thick. WOODWARD- Gravel, sand, silt, clay, caliche, and limestone, locally cemented with calcium carbonate. Generally light-tan to gray to white. Thickness ranges up to 400 feet and probably averages 150 feet. CLINTON- Gray to light-brown, fine- to medium-grained sand with some, clay, silt, gravel, volcanic ash, and caliche beds; locally cemented by calcium carbonate. Thickness ranges from 0 to about 320 feet. The formation thins eastward.
Pleistocene and Pliocene deposits, undifferentiated (Phanerozoic | Cenozoic | Tertiary Quaternary | Pliocene Pleistocene)
TEXAS- Interfingering beds, tongues, and lenses of sand, silt, clay, gravel, sandstone, caliche, limestone, conglomerate, and volcanic ash. Includes Ogallala and Laverne Formations of Pliocene age and younger deposits of Pleistocene age. Locally the units are tightly cemented by calcium carbonate; other places, they are very poorly consolidated and nearly free of cementing materials. Thickness ranges from 0 to about 800 feet.
Terrace Deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
WOODWARD- Lenticular and interfingering deposits of light-tan to gray gravel, sand, silt, clay, and volcanic ash. Sand dunes are common in many places. Thickness ranges up to 150 feet and averages about 60 feet. ENID- Sand, silt, clay, and gravel. Maximum thickness, about 75 feet (23 m) along major streams. TULSA- Fine gravel, sand, silt, and clay. CLINTON- Stream-laid deposits of sand, silt, clay, gravel, and volcanic ash; thickness ranges from 0 to about 120 feet. OKLAHOMA CITY- Lenticular beds of sand, silt, clay, and gravel. Thickness ranges from a few feet to about 100 feet and probably averages about 50 feet along major streams. FORT SMITH- Gravel, sand, silt, and clay. LAWTON- Sand, clay, and gravel as much as 75 feet (23 m) in Tillman County, ranging from 5 to 50 feet (2 to 15 m) elsewhere. ARDMORE-SHERMAN- Gravel, sand, silt, clay, and volcanic ash; thickness, about 5 to 50 feet; at various levels, as high as 160 feet above present flood plains. McALESTER TEXARKANA- Gravel, sand, silt, clay, and volcanic ash; several levels 20 to 160 feet or more above present flood plains, with each level containing deposits that average 20 to 30 feet in thickness, some windblown sand on top; may include colluvial wash down sides of hills
Woodbine Formation (Phanerozoic | Mesozoic | Cretaceous-Late)
McALESTER TEXARKANA- Sand, dark-green, yellowish-red, white, gray, fine- to coarse-grained, tuffaceous in upper part; crossbedded, quartzose, and brownish-red noncalcareous clay; some gravel lentils with little to no quartz and some lignites and fossil plants; rests unconformably upon successively older Cretaceous units eastward; thickness, 325 to 455 feet, increasing eastward.
Oregon
Alluvial deposits (Holocene) (Holocene)
Sand, gravel, and silt forming flood plains and filling channels of present streams. In places includes talus and slope wash. Locally includes soils containing abundant organic material, and thin peat beds
Glacial deposits (Pleistocene) (Pleistocene)
Unsorted bouldery gravel, sand, and rock flour in ground, terminal, and lateral moraines. Locally partly sorted
Glaciofluvial, lacustrine, and pediment sedimentary deposits (Holocene and Pleistocene) (Pleistocene)
Unconsolidated, poorly sorted silt, sand, and gravel. Includes lacustrine deposits west of Columbia River Gorge (Trimble, 1963). Mostly in northern Morrow and Umatilla Counties where unit represents deposits of swollen late Pleistocene Columbia River (Hogenson, 1964)
Lacustrine and fluvial sedimentary rocks (Pleistocene) (Pleistocene)
Unconsolidated to semiconsolidated lacustrine clay, silt, sand, and gravel; in places includes mudflow and fluvial deposits and discontinuous layers of peat. 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). Includes deltaic gravel and sand and gravel bars, in pluvial lake basins in southeastern part of map area. In Rome Basin, includes discontinuous layers of poorly consolidated conglomerate characterized by well-rounded, commonly polished pebbles of chert and pebbles and cobbles of quartzite. In places contains mollusks or vertebrate fossils indicating Pleistocene age; mostly deposits of late Pleistocene age, but locally includes some deposits of early Holocene age. Includes Touchet Beds of Flint (1938), deposits of valley terraces of Newcomb (1965), and, in southeast Oregon, basin-filling deposits that incorporate Mazama ash deposits (Qma, Qmp) in the youngest layers
Loess (Holocene and Pleistocene) (Pleistocene to Holocene)
Windblown clayey silt and fine sand. Includes the Pleistocene Palouse Formation and deposits derived mostly from reworking of Palouse Formation. Contains local interbedded layers of soil, caliche, and some water-laid silt and gravel
Terrace gravels (Pleistocene and Pliocene) (Pliocene to Pleistocene)
Unconsolidated to poorly consolidated, poorly sorted gravels and bouldery soil above modern stream channels. In Cascade Range, clasts mostly basalt and andesite. Includes some glacial outwash deposits. In Eastern Oregon, commonly cemented by caliche
Terrace, pediment, and lag gravels (Holocene and Pleistocene) (Pleistocene to Holocene)
Unconsolidated deposits of gravel, cobbles, and boulders intermixed and locally interlayered with clay, silt, and sand. Mostly on terraces and pediments above present flood plains. Includes older alluvium of Smith and others (1982) in the Klamath Mountains and both high- and low-level terraces along Oregon coast. Includes dissected alluvial fan deposits northeast of Lebanon, and Linn and Leffler Gravels of Allison and Felts (1956)
Pennsylvania
Bryn Mawr Formation (Tertiary)
Bryn Mawr Formation - High-level terrace deposits; reddish-brown gravelly sand and some silt. Age uncertain.
Pensauken and Bridgeton Formations, undifferentiated (Tertiary)
Pensauken and Bridgeton Formations, undifferentiated - Dark-reddish-brown, cross-stratified, feldspathic quartz sand and some thin beds of fine gravel and rare layers of clay or silt.
Trenton Gravel (Quaternary)
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.
South Carolina
Alluvial Valley Swamp (Quaternary)
Alluvial Valley Swamp: Unconformable on all underlying units, fluvial sand and gravel at base, grading upwards into fine sands and silts, local peat. May be overrun with recent sediments from forest cutting and agriculture.
Beach (Holocene)
Beach: Holocene beach complex sediments. Sands and gravels of littoral zone, dune system, barrier system.
Brandywine Formation (Miocene)
Brandywine Formation: Upland gravel similar to Columbia group mapped in the uplands of southern Maryland southeast of DC. 10-40 ft thick. Extensive sand and gravel resources.
Cape Fear/Eutaw Formations (Cretaceous)
Cape Fear/Eutaw Formations Kcfe: Poorly sorted clayey sand and gravel deposited in delta-dominated fluvial- and restricted marine environments. Unit is characterized by an abundance of smoky quartz gravel, feldspar, monazite, and garnet typically concentrated in placer deposits. Generally non-marine from North Carolina to central Georgia but contains shallow-water delta-front deposits in western Georgia.
Neogene strata (undifferentiated) (Neogene)
Neogene strata (undifferentiated): Poorly sorted clayey sand and gravel deposited in a fluvial environment in South Carolina but becoming more fluvio-marine in Georgia. Unit is characterized by insitu weathered feldspar and an abundance of quartzite gravel and cobbles.
South Dakota
Alluvium (Phanerozoic | Cenozoic | Quaternary)
Clay to boulder-size clasts with locally abundant organic material. Thickness up to 75 ft (23m).
Clayely Till, Ground Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Pre-Illinoian])
Heterogeneous, clay to boulder-size clasts of glacial orgin. Exhibits a distinctive weathered, dissected surface. Contains prominent oxidized joints and fractures with gypsum or calcite. Typically overlain by up to 45 ft (14 m) of loess. Thickness of uppermost Pre-Illinoian till may be up to 120 ft (37 m). Composite thickness of all Pre-Illinoian till may be up to 1,000 ft (305 m).
Colluvium (Phanerozoic | Cenozoic | Quaternary)
Clay to boulder-size clasts forming rubble residuum and talus. Thickness up to 30 ft (9m).
Gravel Deposits (Phanerozoic | Cenozoic | Tertiary )
Clay to boulder-size clasts primarily from igneous and metamorphic rocks of the central Black Hills. Also includes Phanerozoic lithic clasts and rare vertebrate fossils. Thickness up to 60 ft (18 m).
Java Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Early)
Sand to gravel of fluvial orgin. Upper portion is tan to reddish-brown eolian silt with minor clay and fine-grained sand. Thickness up to 180 ft (55 m).
Lacustrine Sediments (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Glaciolacustrine clay and silt with minor sand and gravel. Forms flat, low-lying terrain. Includes deposits from Glacial Lake Dakota and Glacial Lake Agassiz. Thickness up to 60 ft (18m).
Lacustrine Sediments, Ice-walled (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Glaciolacustrine clay and silt with minor sand and gravel. Forms elevated level terrain. Thickness up to 60 ft (18m).
Landslide Deposits (Phanerozoic | Cenozoic | Quaternary)
Landslide, slump, and collapsed material composed of chaotically mixed boulders and finer grained rock debris. Thickness up to 180 ft (55m).
Ogallala Group (Phanerozoic | Cenozoic | Tertiary Quaternary | Miocene Pliocene(?) Pleistocene-Early)
Includes: Ash Hollow Formation- White, tan, and gray, well-cemented, calcareous sandstone and silty limestone often referred to as "mortar beds". Thickness 90-250 ft 27-76 m) Valentine Formation- Gray, unconsolidated, fine- to coarse grained, fluvial siltstone, channel sandstone, and gravel derived from western sources. Thickness 175-225 ft (53-69 m). Fort Randall Formation- Pink and gray claystone with interbedded sandstone. Also includes green to gray orthoquartzite, bentonitic clay, and conglomerate. Thickness up to 130 ft (40 m).
Outwash, Collapsed (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous sand and gravel of glaciofluvial orgin. Deposited as outwash sediments that collapsed due to melting of buried ice. Thickness up to 90 ft (27m).
Outwash, Delta (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous sand and gravel of glaciofluvial orgin. Typically forms level terrain at the mouths of meltwater streams which flowed into Glacial Lake Dakota. Thickness up to 30 ft (9m).
Outwash, Ice-walled (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous sand and gravel of glaciofluvial orgin. Typically forms elevated, level terrain. Thickness up to 90 ft (27m).
Outwash, Terrace (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous clay to gravel of glaciofluvial orgin. Thickness up to 60 ft (18m)
Outwash, Undifferentiated (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous sand and gravel, with minor clay and silt. Deposits of glaciofluvial orgin including outwash plains, kame terraces, and other undifferentiated deposits. Thickness up to 30 ft (9m).
Outwash, Undifferentiated (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Illinoian(?) Pre-Illinoian])
Heterogeneous sand and gravel with minor clay of glaciofluvial orgin. Thickness up to 90 ft (27 m).
Outwash, Valley Train (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous silt to gravel. Confined to valleys of glaciofluvial orgin. Thickness up to 60 ft (18m).
Terrace Deposits (Phanerozoic | Cenozoic | Quaternary)
Clay to boulder-size clasts deposited as pediments, paleochannels, and terrace fills of former flood plains. Thickness up to 75 ft (23m).
Till, End Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous, clay with silt to boulder-size clasts of glacial orgin. A geomorphic feature that is characterized by elevated linear ridges with hummocky terrain locally at former ice sheet margins. Composite thicknessof all Upper Wisconsin till may be up to 300 ft (91 m).
Till, Ground Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous, clay with silt to boulder-size clasts of glacial orgin. A geomorphic feature that is characterized by smooth, rolling terrain. Composite thickness of all Upper Wisconsin till may be up to 300 ft (91 m).
Till, Ground Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Illinoian(?)])
Heterogeneous, clay with silt to boulder-size clasts. Exhibits a distinctive weathered, dissected surface. Contains prominent oxidized joints and fractures with gypsum or calcite. Typically overlain by up to 25 ft (8 m) of loess. Thickness up to 120 ft (37 m).
Till, Minor Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous, clay with silt to boulder-size clasts of glacial orgin. A geomorphic feature that is characterized by elevated linear ridges including minor, washboard, or recessional moraines. Composite thicknessof all Upper Wisconsin till may be up to 300 ft (91 m).
Till, Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous, clay with silt to boulder-size clasts of glacial orgin. Exhibits a distinctive weathered, dissected surface.Typically overlain by up to 10 ft (3m) of loess. Thickness up to 150 ft (46 m).
Till, Stagnation Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous, clay with silt to boulder-size clasts of glacial orgin. A geomorphic feature that is characterized by hummocky terrain with abundant sloughs resulting from stagnation of ice sheets. Composite thickness of all Upper Wisconsin till may be up to 300 ft (91 m).
Tennessee
Alluvial deposits (Quaternary)
Alluvial Deposits - Sand, silt, clay, and gravel. In flood plain of Mississippi River more than 100 feet thick; in smaller streams generally less than 20 feet thick.
Alluvial deposits (Quaternary)
Alluvial Deposits - Sand, silt, clay and gravel. Mapped only in valley of Cumberland River and in Elk Valley. Thickness generally less than 30 feet.
Alluvial deposits (Quaternary)
Alluvial Deposits - Sand, silt, clay, and gravel. As much as 60 feet thick in flood plains of Tennessee and Cumberland Rivers; in smaller streams generally less than 20 feet thick.
High-level alluvial deposits (Quaternary-Tertiary)
High-level Alluvial Deposits - Iron-stained gravel, sand, silt, and clay; variable in thickness but generally less then 60 feet thick.
High-Level Alluvial Deposits (Quaternary-Tertiary)
High-Level Alluvial Deposits - Iron-stained gravel, sand, silt, and clay; variable in thickness but generally less than 60 feet thick.
Tuscaloosa Formation (Cretaceous)
Tuscaloosa Formation - Poorly sorted, light-gray chert gravel in a matrix of silt and sand; locally interbedded with sand and clay lenses. Thickness 0 to 140 feet.
Tuscaloosa Formation (Cretaceous)
Tuscaloosa Formation - Poorly sorted, light-gray chert gravel in a matrix of silt and sand; locally interbedded with sand and clay lenses. Thickness 0 to 150 feet.
Texas
alluvium (Phanerozoic | Cenozoic | Quaternary | Holocene)
alluvium
Beaumont Formation, areas predominantly sand (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Late)
Beaumont Formation, areas predominantly sand
Blanco Formation (Phanerozoic | Cenozoic | Tertiary | Pliocene)
Blanco Formation
Double Lakes Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Early Wisconsinan])
Double Lakes Formation
high gravel deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
high gravel deposits
Leona Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
Leona Formation
Lingos Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Middle(?) Pleistocene-Late(?) Holocene)
Lingos Formation
Ogallala Formation (Phanerozoic | Cenozoic | Tertiary | Pliocene Miocene)
Ogallala Formation
older alluvial deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
older alluvial deposits
Onion Creek Marl (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
Onion Creek Marl
Quaternary deposit, undivided (Phanerozoic | Cenozoic | Quaternary)
sand, silt, clay, and gravel. locally indurated with calcium carbonate (caliche); includes point bar, natural levee, stream channel, sand dune, terrace, alluvial fan, landslide bolson and playa deposits
Quaternary-Tertiary deposits, undivided (Phanerozoic | Cenozoic | Tertiary Quaternary | Pliocene Pleistocene)
Quaternary-Tertiary deposits, undivided
Seymour Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Middle [Irvingtonian])
Seymour Formation
Tahoka Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Wisconsinan])
Tahoka Formation
Tarantula Gravel (Phanerozoic | Cenozoic | Tertiary | Miocene)
Tarantula Gravel
Terrace deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Terrace deposits
unnamed Pliocene deposits (Phanerozoic | Cenozoic | Tertiary | Pliocene)
unnamed Pliocene deposits
Uvalde Gravel (Phanerozoic | Cenozoic | Tertiary Quaternary | Pliocene Pleistocene)
Uvalde Gravel
Willis Formation (Phanerozoic | Cenozoic | Tertiary | Pliocene)
Willis Formation
Utah
Quaternary Lake Bonneville deposits (Quaternary)
Virginia
Bacons Castle Formation (Tertiary)
Bacons Castle Formation - Gravel grading upward into sand and sandy clayey silt
Charles City Formation (Quaternary)
Charles City Formation - Interbedded sand, silt, clay and minor gravel; at altitudes to 70-80 ft. (top of unit).
Chuckatuck Formation (Quaternary)
Chuckatuck Formation - Interbedded gravel, sand, silt, clay, and minor peat; at altitudes to 50-60 ft. (top of unit).
Joynes Neck Sand (Quaternary)
Joynes Neck Sand - Fine- to coarse-grained sand coarsening downward to gravel and sand, at altitudes to 26 ft. (top of unit).
Kent Island Formation (Quaternary)
Kent Island Formation - Medium- to coarse-grained sand and sandy gravel grading upward into poorly- to well-sorted fine- to medium-grained sand, in part clayey and silty, at altitudes from sea level to about 20 ft. (top of unit).
Miocene Sand and Gravel (Tertiary)
Miocene Sand and Gravel - Sandy gravel, sand, silt, and clay.
Nassawadox Formation: Butlers Bluff Member (Quaternary)
Nassawadox Formation: Butlers Bluff Member - Fine- to coarse-grained pebbly sand and sandy gravel, at altitudes to 40 ft. (top of unit).
Omar Formation - Accomack Member: (Quaternary)
Omar Formation - Accomack Member: sand, gravel, silt, clay, and peat; at altitudes to 50 ft.
Pliocene Sand and Gravel (Tertiary)
Pliocene Sand and Gravel - Sandy gravel, gravelly sand, poorly to well-sorted sands, and thin- to medium-beds of clay and silt, at altitudes from 170-320 ft. (top of unit).
Quaternary and Tertiary Deposits (Tertiary-Quaternary)
Quaternary and Tertiary Deposits - Tabb through Windsor Formations and alluvial/tidal prism deposits.
Shirley Formation (Quaternary)
Shirley Formation - Interbedded gravel, sand, silt, clay, and peat; at altitudes to 35-45 ft. (top of unit).
Terrace Deposits (Tertiary)
Terrace Deposits - Poorly sorted clay, sand, and rounded pebbles and cobbles, deeply weathered
Windsor Formation (Tertiary-Quaternary)
Windsor Formation - Interbedded gravel, sand, silt, and clay; at altitudes to 85-95 ft. (top of unit).
Washington
Miocene-Pliocene nonmarine rocks (Miocene-Pliocene)
Tuffaceous and pumiceous andesitic sandstone and siltstone with interbedded conglomerate and claystone. Conglomerate beds chiefly andesitic, but also quartzitic, granitic, and basaltic; includes basalt flows locally.
Wyoming
Basalt flows and intrusive igneous rocks (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
BASALT FLOWS AND INTRUSIVE IGNEOUS ROCKS. Yellowstone area--Includes Osprey, Madison River, Swan Lake Flat, and Falls River Basalts, basalts of Mariposa Lake, Undine Falls Basalt, and gravels, sands, silts, and basalts of The Narrows. In and adjacent to Absaroka and Washakie Ranges--Includes basalt of Lava Mountain (age about 0.5 Ma).
Terrace gravel (Phanerozoic | Cenozoic | Tertiary Quaternary | Pliocene Pleistocene)
TERRACE GRAVEL (PLEISTOCENE AND/OR PLIOCENE)--Partly consolidated gravel above and flanking some major streams.

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