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Geologic units containing sedimentary rock

Alabama

Kahatchee Mountain Group; Brewer Phyllite (Precambrian?-Cambrian?)

Brewer Phyllite - dusky-red micaceous slate and phyllite, locally containing interbedded micaceous arkosic quartzite and metasiltstone; locally at the base is interbedded calcite and dolomite marble.

Metaclastic rocks of unknown affinity (Precambrian to Paleozoic)

Metaclastic rocks of unknown affinity - in the area south of Talladega, Talladega County, the unit includes greenish-gray chlorite-sericite phyllite; in small area south of Childersburg the unit consists of greenish-gray chlorite-sericite phyllite and slate locally containing interbeds of metagraywacke; and in the area east of Columbiana, Shelby County, the unit includes dark-greenish-gray slate and metasiltstone containing interbedded coarse-grained to conglomerate quartzite.

Sylacauga Marble Group; Fayetteville Phyllite (Cambrian?-Ordovician?)

Fayetteville Phyllite - dusky-red and medium-gray phyllite and slate interlayered with light-brown to light-gray feldspathic metasiltstone, fine-grained metasandstone and dolomite marble.

Talladega Group; Jemison Chert and Chulafinnee Schist undifferentiated (Silurian?-Devonian)

Jemison Chert and Chulafinnee Schist undifferentiated - grayish-white to yellowish-orange massive, thick-bedded, fine-grained, locally argillaceous, locally fossiliferous metachert and light to dark-greenish-gray fine to medium-grained fissile quartz-sericite-chlorite phyllite and schist which locally includes thin chlorite phyllite and quartzose phyllite beds.

Talladega Group; Lay Dam Formation, unnamed diamictite facies (Silurian?-Devonian)

Talladega Group; Lay Dam Formation, unnamed diamictite facies - Unnamed diamictite facies of Lay Day Formation in Coosa and Chilton Counties consists of cobbles and boulders of carbonate, pelitic rocks, quartzite, chert, felsic plutonic rocks, and gneiss in a metagraywacke matrix.

Arizona

Early Proterozoic metamorphic rocks (Early Proterozoic)

Undivided metasedimentary, metavolcanic, and gneissic rocks. (1600-1800 Ma)

California

pre-Cenozoic granitic and metamorphic rocks undivided (Early Proterozoic to Late Cretaceous)

Granitic and metamorphic rocks, mostly gneiss and other metamorphic rocks injected by granitic rocks. Mesozoic to Precambrian.

Connecticut

Lower part [of Maltby Lakes Metavolcanics] (Middle? Ordovician)

Lower part [of Maltby Lakes Metavolcanics] - Gray-green to green, fine-grained, generally well foliated greenschist, greenstone, and schist or phyllite, composed of albite and chlorite, plus quartz and sericite or epidote and actinolite. Mixed metavolcanics and metasedimentary rocks.

Wepawaug Schist (Devonian or Silurian or both)

Wepawaug Schist - Medium- to dark-gray, medium- to fine-grained, well-layered schist or phyllite and metasiltstone, composed of quartz, muscovite or sericite, plagioclase, biotite, and in appropriate metamorphic zones chlorite, garnet, staurolite, and kyanite. Schist or phyllite generally graphic.

Georgia

Amphibolitic Schist/ Amphibolite-Metagraywacke/ Mica Schist (Precambrian-Paleozoic)

Amphibolitic Schist/ Amphibolite-Metagraywacke/ Mica Schist

Massachusetts

Coal Mine Brook Formation (Middle Pennsylvanian)

Coal Mine Brook Formation - Fossiliferous, carbonaceous slate and garnet phyllite with a lens of meta-anthracite; conglomerate and arkose.

Newbury Volcanic Complex (Lower Devonian and Upper Silurian)

Newbury Volcanic Complex - Undivided sedimentary and volcanic rocks.

Worcester Formation (Lower Devonian and Silurian)

Worcester Formation - Carbonaceous slate and phyllite and minor metagraywacke.

Maryland

Ijamsville Formation (Late Precambrian (?))

Ijamsville Formation - Blue, green, or purple phyllite and phyllitic slate, with interbedded metasiltstone and metagraywacke; flattened pumiceous blebs occur locally.

Ijamsville Formation and Marburg Schist (Late Precambrian (?))

Ijamsville Formation - Blue, green, or purple phyllite and phyllitic slate, with interbedded metasiltstone and metagraywacke; flattened pumiceous blebs occur locally; and Marburg Schist - Bluish-gray to silvery-green, fine-grained, muscovite-chlorite-albite-quartz schist; intensely cleaved and closely folded; contains interbedded quartzites.

Maine

Cambrian Jim Pond Formation (Cambrian)

Cambrian Jim Pond Formation

Ordovician Ammonoosuc Volcanics (Ordovician)

Ordovician Ammonoosuc Volcanics

Ordovician unnamed volcanic and sedimentary rocks (Ordovician)

Ordovician unnamed volcanic and sedimentary rocks

Silurian Sangerville Formation (Silurian)

Silurian Sangerville Formation

Silurian unnamed volcanic and sedimentary rocks (Silurian)

Silurian unnamed volcanic and sedimentary rocks

Michigan

Dickinson Group, undivided (Late Archean) (Late Archean)

Dickinson Group, undivided (Late Archean) - Metavolcanic and metasedimentary rocks in Dickinson County, Mich. From youngest to oldest, consists of Six-Mile Lake Amphibolite, Solberg Schist, and East Branch Arkose.

Minnesota

Mafic metavolcanic rocks (Late Archean)

Mafic metavolcanic rocks - Dominantly basalt that contains thin sedimentary units, including iron-formation. Includes parts of the Ely Greenstone and the Newton Lake Formation in northeastern Minnesota. Also includes metabasalt exposed in the Minnesota River Valley.

Metasedimentary rocks, undivided (Late Archean)

Metasedimentary rocks, undivided - Graywacke, slate, local units of conglomerate, arenite, graphitic slate, fine-grained felsic volcanogenic, and volcaniclastic rocks, lean oxide iron-formation and its metamorphic equivalents. Includes the Knife Lake Group and the Lake Vermilion Formation in northeastern Minnesota.

Mille Lacs Group and related rocks of the Penokean fold-and-thrust belt; Metabasalt, metadiabase, and metasedimentary rocks metamorphosed to lower amphibolite facies (Early Proterozoic)

Mille Lacs Group and related rocks of the Penokean fold-and-thrust belt; Metabasalt, metadiabase, and metasedimentary rocks metamorphosed to lower amphibolite facies - Includes fragmental volcanic rocks, mafic hypabyssal intrusions, graphitic argillite, and oxide iron-formation

Mille Lacs Group and related rocks of the Penokean fold-and-thrust belt; Slate, argillite, and metasiltstone metamorphosed to the lower greenschist facies (Early Proterozoic)

Mille Lacs Group and related rocks of the Penokean fold-and-thrust belt; Slate, argillite, and metasiltstone metamorphosed to the lower greenschist facies - Includes lesser amounts of mafic hypabyssal intrusions, and fragmental mafic volcanic rocks

North Carolina

Battleground Formation (Late Proterozoic)

Battleground Formation - quartz-sericite schist with metavolcanic rock, quartz-pebble metaconglomerate, kyanite-sillimanite quartzite, and garnet-quartz rock.

Chilhowee Group; Lower Chilhowee (Cambrian)

Lower Chilhowee - feldspathic quartzite, white to yellowish gray. Minor silty slate, feldspathic metasiltstone, and metaconglomerate in lower part.

Cid Formation; Felsic Metavolcanic Rock (Cambrian/Late Proterozoic)

(southwest of Asheboro); Felsic Metavolcanic Rock - metamorphosed dacitic to rhyolitic flows and tuffs, light gray to greenish gray; interbedded with mafic and intermediate metavolcanic rock, meta-argillite, and metamudstone.

Cid Formation; Mafic Metavolcanic Rock (Cambrian/Late Proterozoic)

(Southwest of Asheboro); Mafic Metavolcanic Rock - metamorphosed basaltic flows and tuffs, dark green to black; interbedded with felsic and intermediate metavolcanic rock and metamudstone.

Cid Formation; Metamudstone and Meta-Argillite (Cambrian/Late Proterozoic)

(Southwest of Asheboro); Metamudstone and Meta-Argillite - thin to thick bedded; bedding plane and axial-planar cleavage common; interbedded with metasandstone, metaconglomerate, and metavolcanic rock.

Felsic Metavolcanic Rock (Cambrian/Late Proterozoic)

Felsic Metavolcanic Rock - metamorphosed dacitic to rhyolitic flows and tuffs, light gray to greenish gray; interbedded with mafic and intermediate metavolcanic rock, meta-argillite, and metamudstone.

Felsic Metavolcanic Rock (Cambrian/Late Proterozoic)

Felsic Metavolcanic Rock - metamorphosed dacitic to rhyolitic flows and tuffs, light gray to greenish gray; interbedded with mafic and intermediate metavolcanic rock, meta-argillite, and metamudstone.

Floyd Church Formation; Metamudstone and Meta-Argillite (Cambrian/Late Proterozoic)

(Southwest of Asheboro); Metamudstone and Meta-Argillite - thin to thick bedded; bedding plane and axial-planar cleavage common; interbedded with metasandstone, metaconglomerate, and metavolcanic rock.

Mafic Metavolcanic Rock (Cambrian/Late Proterozoic)

Mafic Metavolcanic Rock - metamorphosed basaltic flows and tuffs, dark green to black; interbedded with felsic and intermediate metavolcanic rock and metamudstone.

Mafic Metavolcanic Rock (Cambrian/Late Proterozoic)

Mafic Metavolcanic Rock - metamorphosed basaltic flows and tuffs, dark green to black; interbedded with felsic and intermediate metavolcanic rock and metamudstone.

Metamudstone and Meta-Argillite (Cambrian/Late Proterozoic)

Metamudstone and Meta-Argillite - thin to thick bedded; bedding plane and axial-planar cleavage common; interbedded with metasandstone, metaconglomerate, and metavolcanic rock.

Metavolcanic-Epiclastic Rock (Cambrian/Late Proterozoic)

Metavolcanic-Epiclastic Rock - metamorphosed argillite, mudstone, volcanic sandstone, conglomerate, and volcanic rock.

Metavolcanic-Epiclastic Rock (Cambrian/Late Proterozoic)

Metavolcanic-Epiclastic Rock - metamorphosed argillite, mudstone, volcanic sandstone, and conglomerate, and volcanic rock.

Ocoee Supergroup, Great Smokey Group; Anakeesta Formation (Late Proterozoic)

Anakeesta Formation - slate to schist, dark gray, graphitic and sulfidic; includes interbedded argillaceous, feldspathic metagraywacke.

Ocoee Supergroup, Great Smokey Group; Slate of Copperhill Formation (Late Proterozoic)

Slate of Copperhill Formation - slate to phyllite, dark gray, graphitic, sulfidic; includes metagraywacke with local graded bedding.

Ocoee Supergroup, Great Smokey Group; Wehutty Formation (Late Proterozoic)

Wehutty Formation - slate to schist, dark gray, graphitic and sulfidic; includes mica schist, metagraywacke, and metaconglomerate.

Ocoee Supergroup, Snowbird Group; Longarm Quartzite (Late Proterozoic)

Longarm Quartzite - cross-bedded, feldspathic, locally conglomeratic; includes dark slate and metasiltstone.

Phyllite and Schist (Cambrian/Late Proterozoic)

Phyllite and Schist - minor biotite and pyrite; includes phyllonite, sheared fine-grained metasediment and metavolcanic rock.

Phyllite and Schist (Cambrian/Late Proterozoic)

Phyllite and Schist - locally laminated and pyritic; includes phyllonite, sheared fine-grained metasediment, and metavolcanic rock. In Lilesville granite aureole, includes hornfels.

Phyllite and Schist (Cambrian/Late Proterozoic)

Phyllite and Schist - minor biotite and pyrite; includes phyllonite, sheared fine-grained metasediment and metavolcanic rock.

Rocks of Brevard Fault Zone (Uncertain, possibly Permian or Devonian)

Rocks of Brevard Fault Zone - "fish scale" schist and phyllonite, graphitic; interlayered with feldspathic metasandstone, marble lenses.

Tillery Formation; Metamudstone and Meta-Argillite (Cambrian/Late Proterozoic)

(Southwest of Asheboro); Metamudstone and Meta-Argillite - thin to thick bedded; bedding plane and axial-planar cleavage common; interbedded with metasandstone, metaconglomerate, and metavolcanic rock.

Uwharrie Formation; Felsic Metavolcanic Rock (Cambrian/Late Proterozoic)

(at Asheboro and to south); Felsic Metavolcanic Rock - metamorphosed dacitic to rhyolitic flows and tuffs, light gray to greenish gray; interbedded with mafic and intermediate metavolcanic rock, meta-argillite, and metamudstone.

Volcanic Metaconglomerate (Cambrian/Late Proterozoic)

Volcanic Metaconglomerate - includes metagraywacke and metamudstone.

New Hampshire

Gile Mountain Formation, Interbedded gray slate or phyllite and brown-weathering calcite-ankerite metasiltstone (Lower Devonian)

Interbedded gray slate or phyllite and brown-weathering calcite-ankerite metasiltstone - Contains minor marble and quartzite. Resembles Waits River Formation in Vermont.

Hurricane Mountain Formation (Upper Cambrian?)

Hurricane Mountain Formation - Rusty-weathered, dark siliceous scaly slate or schist of flaser structure, polymictic fragments from a few mm to (in Maine) several hundred meters. A melange consisting of metasedimentary, felsic/mafic metavolcanics, and ultramafic rocks..

Massabesic Gneiss Complex (Late Proterozoic)

Massabesic Gneiss Complex - Migmatite consisting of pink, foliated biotite granite intruding gneissic and granulose metasedimentary and metavolcanic rocks in southeastern New Hampshire.

Partridge Formation, undivided (Middle - Upper Ordovician)

Partridge Formation, undivided - Black, rusty-weathering sulfidic-graphitic slate or schist and sparse to abundant metagraywacke. Lies stratigraphically between upper and lower parts of the Ammonoosuc Volcanics.

Perry Mountain and Rangeley Formations, undivided (Silurian)

Perry Mountain and Rangeley Formations, undivided.

Perry Mountain Formation, undivided (Lower? - Middle? Silurian)

Perry Mountain Formation, undivided - Sharply interbedded quartzites, light-gray nongraphitic metapelite, and "fast-graded" meta-turbidites. Coticule layers common.

New Mexico

basaltic and andesitic volcanics interbedded with sedimentary units (Phanerozoic | Cenozoic | Tertiary Quaternary)

Basaltic and andesitic volcanics interbedded with Pleistocene and Pliocene sedimentary units

middle and upper Jurassic rocks, unidivided (Phanerozoic | Mesozoic | Jurassic)

Jurassic rocks, Middle and Upper, undivided

Morrison Formation and upper San Rafael Group (Phanerozoic | Mesozoic | Jurassic)

Morrison Formation and upper San Rafael Group

Ordovician and Cambrian rocks, undivided (Phanerozoic | Paleozoic | Cambrian Ordovician)

Ordovician and Cambrian rocks, undivided; includes Bliss Sandstone, El Paso Formation, and Montoya Formation (or Group)

Paleozoic rocks, undivided (Phanerozoic | Paleozoic)

Paleozoic rocks, undivided

Pennsylvanian rocks, undivided (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian)

Pennsylvanian rocks, undivided; in Sangre de Cristo Mountains may include Sandia Formation, Madera Limestone, La Pasada, Alamitos, and Flechado Formations; elsewhere may include Bar-B, Nakaye, Red House, Oswaldo, and Syrena Formations

Permian Rocks, undivided (Phanerozoic | Paleozoic | Permian)

Permian rocks, undivided

Silurian and Ordovician rocks, undivided (Phanerozoic | Paleozoic | Ordovician Silurian)

Silurian and Ordovician rocks, undivided

Silurian through Cambrian rocks, undivided (Phanerozoic | Paleozoic | Cambrian Ordovician(?) Silurian)

Silurian through Cambrian rocks, undivided

Nevada

Intrusive rocks of mafic and intermediate composition (Miocene to Quaternary)

INTRUSIVE ROCKS OF MAFIC AND INTERMEDIATE COMPOSITION

Landslide deposits (Quaternary)

LANDSLIDE DEPOSITS

Sedimentary rocks (Pliocene to Quaternary)

SEDIMENTARY ROCKS-Mostly lake deposits

New York

Walloomsac Formation (Middle Ordovician)

Walloomsac Formation - phyllite, schist, metagraywacke.

Walloomsac Formation (Middle Ordovician)

Walloomsac Formation - slate, phyllite, schist, metagraywacke.

Oregon

Sedimentary and volcaniclastic rocks (Tertiary)

Lapilli tuff, mudflow deposits (lahars), flow breccia, and volcanic conglomerate, mostly of basaltic to dacitic composition; rare iron-stained palagonitic tuff and breccia of basaltic and andesitic composition; and ash-flow, air-fall, and water-laid tuff of dacitic to rhyolitic composition. The palagonite tuff and breccia grade laterally into peperite and into lava flows of basalt and basaltic andesite

Rhode Island

Narragansett Bay Group - Rhode Island Formation (Pennsylvanian)

Narragansett Bay Group - Rhode Island Formation - In northern Rhode Island, consists of gray to black, fine- to coarse-grained quartz arenite, litharenite, shale, and conglomerate, with minor beds of anthracite and meta-anthracite. In southern Rhode Island, consists of meta-sandstone, meta-conglomerate, schist, carbonaceous schist, and graphite. Plant fossils are common.

Narragansett Pier Plutonic Suite - leucocratic granite (Permian)

Narragansett Pier Plutonic Suite - leucocratic granite - White to gray leucocratic granite composed of microcline, oligoclase, and quartz. Up to 10% accessory muscovite and garnet, with lesser apatite, zircon, and monazite. Biotite and opaque minerals notably sparse or absent. Mainly massive, but locally exhibits flow foliation caused by alternating layers of pegmatite, aplite, and medium-grained equigranular granite; pegmatitic and aplitic material of mineralogy similar to the host granite. The granite contains widespread xenolithic inclusions and screens of metasedimentary rock, some of which are PAnbr; bedding and fabric in the screens generally is oriented parallel to that in the host metasedimentary country rock. Unit is a 5 km by 40 km batholith that underlies the southern coast of RI. Intrusion during the latter part of Alleghanian deformation of the Narragansett Basin is indicated by its Permian age, rapid cooling, and field relations. The age of the Narragansett Pier is well constrained by several factors. Brown and others (1978) report a Pennsylvanian fossil contained in an inclusion in the pluton. Radiometric ages of 276 Ma by Kocis and others (1978), 272+/-4 Ma by Hermes and others (1981), and 273+/-2 Ma by Zartman and Hermes (1987) are consistently Early Permian. Structural studies by Mosher (1983) and Reck and Mosther (1988) indicate that intrusion began during the third period of deformation in the Narragansett Basin. Argon release patterns (Dallmeyer, 1982) indicate that the granite and intruded sediments had cooled below argon retention temperatures of hornblende by the Late Permian and of biotite by the Early Triassic. Intruded by the Westerly Granite, which has been radiometrically dated at 276+/-7 Ma. The two granites are probably genetically related based on similarities in age, mineralogy, and geochemistry (Hozik, 1992).

Texas

Lost Creek Gneiss (preCambrian-Proterozoic)

Lost Creek Gneiss

Virginia

Aaron Slate (Proterozoic Z)

Aaron Slate - Phyllite and slate.

Candler Formation - Phyllite and schist (Cambrian)

Candler Formation - Phyllite in central Blue Ridge Anticlinorium; Phyllite, metasiltstone and quartz-mica schist in southwest Blue Ridge Anticlinorium

Interlayered Mafic and Felsic Volcanic Rocks (Proterozoic Z)

Interlayered mafic and felsic metavolcanic rocks.

Lynchburg Group; Graphitic phyllite and metasiltstone (Proterozoic Z)

Lynchburg Group - Graphitic phyllite and metasiltstone

Mafic Volcanic Rocks (Proterozoic Z)

Mafic volcanic rocks.

Mather Gorge Formation -- Schist (Proterozoic Z-Cambrian)

Mather Gorge Formation - Schist.

Washington

Pre-Carboniferous intrusive rocks (Paleozoic)

Meta-quartz diorite, hypersthene diorite, and gneissose and directionless quartz diorite of eastern Skagit County. Quartz diorite and diorite in the San Juan Islands. Includes amphibolite and gneiss locally.

Pre-Middle Jurassic sedimentary and volcanic rocks (Late Paleozoic deposition? with Cretaceous metamorphism?)

Sedimentary and volcanic rocks, undivided. Graywacke, argillite, slate, greenstone, and spilitic volcanic rocks.

Pre-Tertiary sedimentary and metasedimentary rocks, undivided (Mostly Early Cretaceous to Middle Jurassic, possibly includes minor Eocene rocks)

Graywacke, argillite, phyllite, chert, talc, and graphite schist; some faulted-in blocks of serpentinite and greenstone. Includes minor limestone on San Juan Island.

Pre-Tertiary volcanic rocks, undivided (Probably mostly Jurassic)

Andesite and basalt flows, and greenstone; includes minor interbedded limestone, arkose, quartzite, and chert beds.

Pre-Upper Jurassic metamorphic rocks of the medium and high-grade zone (Early Jurassic-Triassic)

Schist, amphibolite, and minor lime-silicate rocks, marble, quartzite, and metaconglomerate.

Triassic sedimentary rocks, undivided (Triassic with Permian where impossible to differentiate)

Predominantly limestone, marble, and dolomite near Riverside in Okanogan County. Conglomerate, shale, graywacke, gritstone, and limestone on San Juan Island. Siltstone with greenstone locally on Orcas Island. Graywacke conglomerate, cherty greenstone, and limestone in northern Ferry County.

Upper Jurassic-Lower Cretaceous volcanic rocks (Jurassic-Cretaceous on San Juan Islands; possibly Eocene in King County)

Predominantly volcanic rocks, mostly metamorphosed to greenstone and greenschist; includes some sedimentary rocks

Upper Paleozoic rocks, undivided (Ordovician)

Mostly graywacke, interbedded quartzite and phyllite, greenstone and serpentine, and black shale with minor limestone. Some quartz-mica schist in Bald Knob area of Ferry County. Schist, gneiss, and amphibolite in other parts of Ferry County. Some rocks of lower Paleozoic age, possibly Precambrian, and Mesozoic may be included.

Wyoming

Mesozoic and Paleozoic rocks (Phanerozoic | Paleozoic Mesozoic | Carboniferous Mississippian-Late Pennsylvanian(?) Permian(?) Triassic(?) Jurassic(?) Cretaceous-Late)

MESOZOIC AND PALEOZOIC ROCKS (north Wyoming). Shown in small areas of complex structure. East Flank of Absaroka Range--Dinwoody Formation, Phosphoria Formation and related rocks., Tensleep Sandstone, and Amsden Formation (Lower Triassic through Upper Mississippian). East flank of Bighorn Mountains--Cloverly, Morrison, Sundance, Gypsum Spring, Chugwater and Gypsum Spring Formations (Lower Cretaceous through Permian). MESOZOIC AND PALEOZOIC ROCKS (south Wyoming). Shown in small areas of complex structure. South side of Granite Mountains north of Green Mountain--Nugget Sandstone, Chugwater and Goose Egg Formations, Tensleep Sandstone, and Amsden Formation (Jurassic? through Upper Mississippian). South flank of Ferris Mountains--Nugget Sandstone and Chugwater and Goose Egg Formation (Jurassic? through Permian). Northeast flank of Seminoe Mountians--Cloverly, Morrison, Sundance, Chugwater, and Goose Egg Formations (Lower Cretaceous through Permain). West flank of Sierra Madre--Chugwater, Goose Egg, Casper, and Fountain Formations (Upper Triassic through Middle Pennsylvanian). East Flank of Laramie Mountains--Cloverly, Morrison, Sundance, Chugwater, and Goose Egg Formations, and, east of fault in T. 19 N., Casper Formation (Lower Creatceous through Middle Pennsylvanian). NUGGET SANDSTONE in south--Gray to dull-red, massive to coarsely crossbedded quartz sandstone.