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Geologic units containing meta-conglomerate

Alabama

Jacksons Gap Group; Tallassee Metaquartzite (Precambrian to Paleozoic)

Jacksons Gap Group; Tallassee Metaquartzite - medium to fine-grained, massive to thin-bedded quartzite and metaconglomerate and thin beds of graphitic quartz schist, locally contains small garnets.

Kahatchee Mountain Group; Kalona Quartzite Member of Wash Creek Slate (Precambrian?-Cambrian?)

Kalona Quartzite Member of Wash Creek Slate - light-brown to light-gray coarse-grained, feldspathic quartzite and metaconglomerate in lower part of Wash Creek Slate.

Talladega Group; Cheaha Quartzite Member of Lay Dam Formation (Silurian?-Devonian)

Cheaha Quartzite Member of Lay Dam Formation - white to light-gray medium to coarse-grained arkosic quartzite and metaconglomerate.

Talladega Group; Lay Dam Formation (Silurian?-Devonian)

Lay Dam Formation (Talladega Group) - interbedded dark-green phyllite, medium-gray to light-brown and black metasiltstone, dark-green feldspathic metagraywacke, and light-gray and dark-gray medium to coarse-grained arkosic quartzite and metaconglomerate; graphitic phyllite common in upper part. In Cleburne and Calhoun Counties, rocks mapped as the Lay Dam include the Abel Gap Formation of Bearce (1973) and consist of interbedded greenish-gray metasiltstone and quartzite, black phyllitic metasiltstone, medium-gray to greenish-gray arkosic quartzite, and dark-gray pyritic quartzite. In Clay Chounty the upper part of the Lay Dam includes black graphitic sericite phyllite and slate reportedly containing plant fossils (Erin Slate Member).

Talladega Group; Miller Mill Quartzite Member of the Lay Dam Formation (Silurian?-Devonian)

Miller Mill Quartzite Member of the Lay Dam Formation - white to medium-gray medium to coarse-grained arkosic quartzite and metaconglomerate.

Arizona

Cretaceous to Late Jurassic sedimentary rocks with minor volcanic rocks (Late Jurassic to Cretaceous)

Sandstone and conglomerate, rarely forms prominent outcrops; massive conglomerate is typical near base of unit and locally in upper part. These deposits are nonmarine except in southeastern Arizona, where prominent gray marine limestone (Mural Limestone) forms the middle of the Bisbee Group. Sandstones are typically medium-bedded, drab brown, lithic-feldspathic arenites. Includes Bisbee Group (largely Early Cretaceous) and related rocks, Temporal, Bathtub, and Sand Wells formations, rocks of Gu Achi, McCoy Mountains Formation, and Upper Cretaceous Fort Crittenden Formation and equivalent rocks. (80-160 Ma)

Jurassic sedimentary and volcanic rocks (Jurassic)

Sandstone and conglomerate derived from volcanic rocks with associated intermediate-composition lava flows, breccias, and tuffs. In southern Arizona this unit includes rocks of the Artesa sequence, Pitoikam Formation, Mulberry Wash volcanics, Rudolfo Red Beds, Recreation Red Beds, and Gardner Canyon Formation. In western Arizona it includes the Harquar Formation, rocks of Slumgullion, and related(?) unnamed units in the Kofa and Middle Mountains. This unit is characterized by maroon, brown, and purplish-gray volcanic-lithic sandstone and siltstone, with subordinate to abundant conglomerate, quartz-rich sandstone and sparse limestone. (150-170 Ma)

Jurassic to Cambrian metamorphosed sedimentary rocks (Cambrian to Jurassic)

Highly faulted and folded rocks of units Jv, J_, and Pz, deformed and metamorphosed in Jurassic, Cretaceous and Tertiary time. This unit is restricted to west-central Arizona. (160-540 Ma)

Jurassic volcanic rocks (Jurassic)

Massive quartz-feldspar porphyry, generally interpreted as thick, welded rhyolitic tuffs, with locally abundant lava, and sandstone and conglomerate derived from volcanic rocks. Rare eolian quartzite units are interbedded in southern Arizona. Includes Ali Molina Formation, Mount Wrightson Formation, part of the Canelo Hills Volcanics, Cobre Ridge tuff, Black Rock volcanics, Planet Volcanics, and equivalent rocks. (160-200 Ma)

Middle Proterozoic sedimentary rocks (Middle Proterozoic)

Red-brown shale and sandstone, buff to orange quartzite, limestone, basalt, black shale, and sparse conglomerate. This unit includes the Grand Canyon Supergroup, Apache Group, and Troy Quartzite. These rocks were deposited in shallow marine, coastal nonmarine, and fluvial settings. (700-1300)

Georgia

Undifferentiated pelitic rocks (Precambrian-Paleozoic)

Undifferentiated pelitic rocks, includes mica schists, metasiltstones, metaconglomerates, and metagraywackes

Idaho

Meta-conglomerate mafic metavolcanic rocks, siltite, argillite, and limestone; Late Proterozoic rifted continental margin; northwestern Idaho (Late Proterozoic)

Younger Precambrian mafic volcanic flows and conglomerates of northern Idaho.

Metasedimentary and metavolcanic rocks; Permian greenschist-facies rocks; western Idaho, Blue Mountains island-arc complex (Late Permian)

Upper Permian submarine volcanic complex in the Snake Canyon of western Idaho.

Metavolcanic and metasedimentary rocks; Jurassic greenschist-facies metamorphic rocks; western Idaho, Blue Mountains island-arc complex (Jurassic)

Jurassic mixed marine detrital and volcanic rocks of western Idaho.

Metavolcanic and metasedimentary rocks; Middle to Lower Triassic greenschist-facies metamorphic rocks; western Idaho, Blue Mountains island-arc complex (Middle and Early Triassic)

Middle and Lower Triassic metabasalt and submarine volcaniclastics of western Idaho

Quartzite, marble, Calc-silicate rock, schist, and meta-conglomerate; Ordovician to Middle Proterozoic metasedimentary rocks; central Idaho, Pioneer Mountains metamorphic core complex (Ordovician to Middle Proterozoic)

Ordovician to Middle Proterozoic metasedimentary rocks, undivided

Quartzite, meta-conglomerate, dolostone, argillite; Middle Proterozoic Swauger quartzite; southern Belt province (Middle Proterozoic)

Intermediate Precambrian sediments, red-tinted quartzite with minor conglomeratic and dolomitic lenses of southern Idaho

Maryland

Cardiff Metaconglomerate (Late Precambrian (?))

Cardiff Metaconglomerate - Silvery-gray, well foliated, micaceous quartz-pebble metaconglomerate and quartzite; apparent maximum thickness 700 feet.

Wissahickon Formation; Metaconglomerate (Late Precambrian (?))

Wissahickon Formation; Metaconglomerate - Silvery-gray, well foliated, micaceous quartz-pebble metaconglomerate and quartzite; thickness about 1,200 feet at Deer Creek, Harford County.

Michigan

Baraga Group; Copps Formation (Early Proterozoic)

Baraga Group; Copps Formation - Fine- to medium-grained graywacke and less abundant gray to black slate. Thin basal conglomerate west of Lake Gogebic contains clasts of underlying Archean rocks in a quartzitic and argillaceous matrix.

Montana

Grinnell argillite (Proterozoic | Mesoproterozoic)

Grinnell argillite: reddish-purple and green argillite, quartzitic argillite, and some quartzite; generally contains some feldspar and carbonates.

Helena limestone (Proterozoic | Mesoproterozoic)

Helena limestone: gray, unevenly laminated limestone, argillaceous and dolomitic; weathers light brown or yellow. Segregation structures and stromatolites are common. Distinguished only in general vicinity of Helena.

Missoula group (Proterozoic | Mesoproterozoic)

Missoula group: chiefly red, maroon, or purple argillite; sandy or quartzitic argillite, and generally impure quartzite and limestone. The larger limestone masses are similar to the Siyeh limestone of the Piegan group. The Missoula group includes numerous named formations, most of which cannot be traced with confidence far from their type localities. Among these are the Marsh shale in the Helena region, the Striped Peak and Libby formations in northwestern Montana, five near Missoula, and others in and south of Glacier National Park.

Missoula group (Proterozoic | Mesoproterozoic)

Missoula group: chiefly red, maroon, or purple argillite; sandy or quartzitic argillite, and generally impure quartzite and limestone. The larger limestone masses are similar to the Siyeh limestone of the Piegan group. The Missoula group includes numerous named formations, most of which cannot be traced with confidence far from their type localities. Among these are the Marsh shale in the Helena region, the Striped Peak and Libby formations in northwestern Montana, five near Missoula, and others in and south of Glacier National Park.

North Boulder group (Proterozoic | Mesoproterozoic)

North Boulder group: greenish-gray coarse conglomerate at base, with arkose, conglomerate, and sandy and silty strata above. Locally includes strata resembling the Greyson and Spokane shales, thought to rest directly on the pre-Belt complex of metamorphic rocks. Some areas shown as Spokane shale, and possibly other units may include rocks of the North Boulder group. Distinguished from the vicinity of North Boulder River eastward along and north of Jefferson River and in the Bridger Range.

North Carolina

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.

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.

Metamudstone and Meta-Argillite (Cambrian/Late Proterozoic)

Metamudstone and Meta-Argillite - bedding plane and axial-planar cleavage common; interbedded with metasandstone, meta-conglomerate, and metavolcanic rock.

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.

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.

Volcanic Metaconglomerate (Cambrian/Late Proterozoic)

Volcanic Metaconglomerate - includes metagraywacke and metamudstone.

New Hampshire

Clough Quartzite (Lower Silurian (upper Llandoverian))

Clough Quartzite - Orthoquartzite, quartz metaconglomerate, muscovite schist, minor polymictic metaconglomerate. Disconformable below Fitch Formation and unconformable on Ordovician formations. Equivalent, in part, to member C of Rangeley Formation of Maine. Fossiliferous.

Fitch and Clough Formations, undivided (Silurian)

Fitch and Clough Formations, undivided.

Littleton Formation, Metaconglomerate and quartzite (Lower Devonian)

Littleton Formation, Metaconglomerate and quartzite - Locally fossiliferous in Whitefield quadrangle.

Lower part of Rangeley Formation (Lower Silurian (Llandoverian))

Lower part of Rangeley Formation - Gray, thinly laminated (5-25 mm) metapelite with local lentils of turbidites and thin quartz conglomerates in western New Hampshire. Sparse calc-silicate pods and coticule. Probably equivalent to member B of Rangeley Formation of Maine.

Smalls Falls Formation, Metaconglomerate member (Upper to Middle Silurian (Ludlovian and Wenlockian))

Smalls Falls Formation, Metaconglomerate member - Found in Errol quadrangle in northern New Hampshire.

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.

Other metasedimentary rocks - metaclastic rock, undivided (Pennsylvanian? or Late Proterozoic?)

Other metasedimentary rocks - metaclastic rock, undivided - Red to gray to green polymict conglomerate, sandstone, and shale. Variably metamorphosed. Includes rock mapped formerly as Bellingham Conglomerate.

Virginia

Aaron Slate (Proterozoic Z)

Aaron Slate - Metaconglomerate.

Lunga Reservoir Formation (Cambrian)

Lunga Reservoir Formation - Metadiamictite.

Purcell Branch Formation (Cambrian)

Purcell Branch Formation - Metadiamictite.

Swift Run Formation (Proterozoic Z)

Swift Run Formation - Phyllite, metasandstone, and metaconglomerate.

Washington

Precambrian conglomerate (Late-Proterozoic)

Gray-brown, coarse, poorly sorted pebbles and cobbles of limestone, dolomite, reddish-brown quartzite, black slate or phyllite, and rarely granitic rocks in a gray sandy phyllite matrix; northeastern Pend Oreille County and southwestern Stevens County. Rocks become finer grained and more schistose and the unit becomes thicker toward the southwest, where there is included an isolated subunit which may be a tillite, consisting of cobbles, boulders, and blocks of argillite and carbonate rocks in a fine silty matrix.