Geologic units in Nevada (state in United States)

Mineral Resources On-Line Spatial Data

Older basalt rocks (Early Oligocene to Early Miocene) at surface, covers < 0.1 % of this area

OLDER BASALT ROCKS

Granitic rocks, western Nevada (Jurassic to Cretaceous) at surface, covers 0.2 % of this area

GRANITIC ROCKS, WESTERN NEVADA (Mesozoic)-Mostly quartz monzonite and granodiorite. Inconclusively dated or not dated radiometrically

Lithology: granodiorite; quartz monzonite; granite; quartz diorite; gabbro

Breccia (Middle Eocene to Early Pliocene) at surface, covers < 0.1 % of this area

BRECCIA-Volcanic, thrust, and jasperoid breccia and landslide megabreccia

Lithology: volcanic breccia (agglomerate); tectonite; landslide

Argillaceous limestone, chert, and shale (Devonian) at surface, covers < 0.1 % of this area

ARGILLACEOUS LIMESTONE, CHERT, AND SHALE-Elko and Eureka Counties

Lithology: limestone; shale; chert; siltstone; sandstone

Upper Cambrian carbonate rocks in western Utah (Middle Cambrian to Early Ordovician) at surface, covers < 0.1 % of this area

Lithology: limestone; dolostone (dolomite); shale

Welded and nonwelded silicic ash-flow tuffs (Early Oligocene to Early Miocene) at surface, covers 7 % of this area

WELDED AND NONWELDED SILICIC ASH-FLOW TUFFS-Locally includes thin units of air-fall tuff and sedimentary rock

Lithology: rhyolite; dacite; trachyte

Granitic rocks (Middle Triassic to Early Jurassic) at surface, covers < 0.1 % of this area

GRANITIC ROCKS-Quartz monzonite in northern Esmeralda County

Lithology: granite; granodiorite; quartz monzodiorite

Dolomite, limestone, and minor amounts of sandstone and quartzite (Devonian) at surface, covers 1 % of this area

DOLOMITE, LIMESTONE, AND MINOR AMOUNTS OF SANDSTONE AND QUARTZITE-Includes units such as Sevy and Simonson Dolomites, Guilmette and Nevada Formations, and Devils Gate Limestone.

Lithology: dolostone (dolomite); limestone; sandstone; quartzite; conglomerate; shale; chert

Limestone, dolomite, shale, and quartzite (Ordovician) at surface, covers 1 % of this area

LIMESTONE, DOLOMITE, SHALE, AND QUARTZITE-Includes units such as Pogonip Group, Eureka Quartzite, and Ely Springs Dolomite. Where Ely Springs Dolomite or equivalent rocks are included in SOc unit, this unit includes only the Pogonip Group and Eureka Quartzite or their equivalents.

Lithology: limestone; dolostone (dolomite); shale; quartzite; chert

Granitic rocks (Cretaceous) at surface, covers 2 % of this area

GRANITIC ROCKS-Mostly quartz monzonite and granodiorite

Lithology: granodiorite; quartz monzonite; granite; peraluminous granite

Sedimentary rocks (Late Cretaceous to Oligocene) at surface, covers 0.2 % of this area

SEDIMENTARY ROCKS-Includes Sheep Pass Formation (Eocene) and related units and unnamed tuffaceous sedimentary rocks

Lithology: sandstone; conglomerate; limestone; siltstone; claystone; mudstone; shale; tuff; oil shale

Tuffaceous sedimentary rocks (Late Eocene to Late Miocene) at surface, covers 5 % of this area

TUFFACEOUS SEDIMENTARY ROCKS-Locally includes minor amounts of tuff

Lithology: sandstone; limestone; siltstone; conglomerate; mudstone; dolostone (dolomite); felsic volcanic rock; intermediate volcanic rock; mafic volcanic rock; tuff

Andesite and basalt flows (Early Miocene to Early Pliocene) at surface, covers 3 % of this area

ANDESITE AND BASALT FLOWS-Mostly in about 17 to about 6 m.y. age range. In Humboldt County, locally includes rocks as old as 21 m.y. May include rocks younger than 6 m.y. in places

Lithology: basalt; andesite; shoshonite

Koipato Group and related rocks (Permian to Early Triassic) at surface, covers 0.2 % of this area

KOIPATO GROUP AND RELATED ROCKS (Lower Triassic)-Altered andesitic flows, rhyolitic tuffs and flows, and clastic rocks. Includes rocks mapped by Silberling (1959) as Pablo Formation and originally considered to be Permian in the Shoshone Mountains, Nye County. Includes Tallman Fanglomerate (Permian?) in Humboldt County

Lithology: rhyolite; andesite; clastic; basalt

Phyllitc siltstone, quartzite, and lesser amounts of limestone and dolomite (Late Proterozoic to Early Cambrian) at surface, covers 0.2 % of this area

PHYLLITIC SILTSTONE, QUARTZITE, AND LESSER AMOUNTS OF LIMESTONE AND DOLOMITE-Includes Reed Dolomite; Deep Spring, Campito, Poleta, Harkless, and Saline Valley Formations; and Mule Spring Limestone

Lithology: siltstone; limestone; dolostone (dolomite); quartzite; sandstone

Rhyolitic flows and shallow intrusive rocks (Miocene to Quaternary) at surface, covers < 0.1 % of this area

RHYOLITIC FLOWS AND SHALLOW INTRUSIVE ROCKS

Lithology: rhyolite; trachybasalt; latite; dacite; trachyte

Siltstone, sandstone, limestone, and dolomite (commonly silty or sandy) and gypsum (Early Permian) at surface, covers 0.8 % of this area

SILTSTONE, SANDSTONE, LIMESTONE, AND DOLOMITE (COMMONLY SILTY OR SANDY), AND GYPSUM (Lower Permian)-Includes units such as Rib Hill Sandstone and Pequop Formation of Steele (1959) in Elko County, Rib Hill Sandstone and Arcturus Formation in White Pine County, Queantoweap Sandstone of NcNair (1951), Hermit Shale, and Coconino Sandstone in Clark and southern Lincoln Counties.

Lithology: sandstone; limestone; shale; siltstone; dolostone (dolomite); evaporite (gypsum); chert; quartzite

Continental deposits of siltstone, shale, conglomerate, and limestone (Cretaceous) at surface, covers < 0.1 % of this area

CONTINENTAL DEPOSITS OF SILTSTONE, SHALE, CONGLOMERATE, AND LIMESTONE-Includes units such as King Lear Formation in Humboldt County, Newark Canyon Formation in Eureka County, Willow Tank Formation and baseline Sandstone in Clark County

Lithology: conglomerate; sandstone; limestone; mudstone; siltstone

Rhyolitic flows and shallow intrusive rocks (Middle Miocene to Late Miocene) at surface, covers 3 % of this area

RHYOLITIC FLOWS AND SHALLOW INTRUSIVE ROCKS

Lithology: rhyolite; dacite; trachyte

Andesite and related rocks of intermediate composition (Early Oligocene to Early Miocene) at surface, covers 1 % of this area

ANDESITE AND RELATED ROCKS OF INTERMEDIATE COMPOSITION-Flows and breccias

Lithology: andesite; trachyte; dacite

Welded and nonwelded silicic ash-flow tuffs (Middle Miocene to Late Miocene) at surface, covers 3 % of this area

WELDED AND NONWELDED SILICIC ASH-FLOW TUFFS-Locally includes thin units of air-fall tuff and sedimentary rock

Lithology: rhyolite

Rhyolitic intrusive rocks (Eocene to Miocene) at surface, covers < 0.1 % of this area

RHYOLITIC INTRUSIVE ROCKS

Lithology: granitoid

Diorite (Jurassic to Cretaceous) at surface, covers < 0.1 % of this area

Lithology: diorite; quartz diorite; gabbro; granite; granodiorite; serpentinite

Rhyolite and dacite (Pliocene? and Miocene) (Miocene to Pliocene) at surface, covers < 0.1 % of this area

Ash-flow tuff, lava flows, pumice-lapilli tuff, coarse pumicite, flow breccia, and domal complexes of rhyolitic, rhyodacitic, and dacitic composition; in places includes peralkaline rhyolite and some andesite and andesite breccia. Locally porphyritic with phenocrysts of alkali feldspar, plagioclase, and minor augite, ferro-hedenbergite, hornblende, hypersthene, or biotite. Commonly flow banded; locally glassy. Many of the ash--flow tuffs exhibit flow features and only obscure vitro-clastic textures. In places includes interlayers of silicic volcaniclastic rocks and tuffaceous sedimentary rocks. Includes rhyolite at Owyhee Dam, Jump Creek Rhyolite, and Littlefield Rhyolite, all of Kittleman and others (1965); Dooley Rhyolite Breccia of Gilluly (1937), radiometrically dated at 14.7 +/- 0.4 Ma by potassium-argon methods (Fiebelkorn and others, 1983); resurgent domal masses in McDermitt caldera area; and extensive unnamed flows and ash-flow tuffs in the central and southern part of the Owyhee Upland. Also includes isolated masses of dacitic and rhyodacitic flows, breccia, and ash-flow tuff along eastern slope of Cascade Range that are lapped by flows and sediments of the Madras (or Deschutes) Formation. Potassium-argon ages on rocks in unit from southeast Oregon range from about 13 to 16 Ma; lenses of interbedded tuffaceous sedimentary rocks locally contain a Miocene (Barstovian) vertebrate fauna

Lithology: rhyolite; dacite; andesite

Basalt flows (Miocene to Quaternary) at surface, covers 0.6 % of this area

BASALT FLOWS-Locally includes maar deposits

Lithology: basalt; andesite; trachybasalt; latite; andesite

Devonian sedimentary rocks in western Utah (Devonian to Mississippian) at surface, covers < 0.1 % of this area

Lithology: dolostone (dolomite); limestone; siltstone; mudstone

Granitic rocks (Jurassic) at surface, covers 0.6 % of this area

GRANITIC ROCKS-Mostly quartz monzonite and granodiorite

Lithology: quartz monzonite; granodiorite; granite; monzonite; quartz diorite; peraluminous granite

Limestone and dolomite, locally thick sequences of shale and siltstone (Late Cambrian to Middle Cambrian) at surface, covers 1 % of this area

LIMESTONE AND DOLOMITE, LOCALLY THICK SEQUENCES OF SHALE AND SILTSTONE-Includes units such as Pioche Shale, Eldorado Dolomite, Geddes Limestone, Secret Canyon Shale, Hamburg Dolomite, Dunderberg Shale, and Windfall Formation of northern Nevada and Carrara, Bonanza King, and Nopah Formations of southern Nevada.

Lithology: limestone; dolostone (dolomite); shale; siltstone; sandstone; chert; conglomerate

Limestone, minor amounts of dolomite, shale, and sandstone; locally thick conglomerate units (Triassic) at surface, covers 0.3 % of this area

LIMESTONE, MINOR AMOUNTS OF DOLOMITE, SHALE, AND SANDSTONE; LOCALLY THICK CONGLOMERATE UNITS (Lower, Middle, and Upper Triassic)-Includes Tobin, Dixie Valley, Favret, Augusta Mountain, and Cane Spring Formations and Star Peak Group in central Nevada and Grantsville and Luning Formations in west-central Nevada

Lithology: limestone; dolostone (dolomite); shale; sandstone; conglomerate; siltstone; andesite; chert

Sedimentary rocks (Pliocene to Quaternary) at surface, covers 0.2 % of this area

SEDIMENTARY ROCKS-Mostly lake deposits

Lithology: lake or marine deposit (non-glacial); sedimentary rock

Intrusive rocks (Late Cretaceous to Middle Miocene) at surface, covers 0.2 % of this area

INTRUSIVE ROCKS-Aphanitic, porphyritic, and coarsely granular rocks ranging in composition from diorite to granite. Clark County

Lithology: alkali-granite (alaskite); granite; granodiorite; tonalite; diorite; peraluminous granite

Intrusive rocks of mafic to intermediate composition (Eocene to Miocene) at surface, covers < 0.1 % of this area

INTRUSIVE ROCKS OF MAFIC TO INTERMEDIATE COMPOSITION

Lithology: diorite; monzodiorite; quartz diorite; quartz monzogabbro; tonalite; gabbro

Alluvial deposits (Quaternary) at surface, covers 42 % of this area

ALLUVIAL DEPOSITS-Locally includes beach and sand dune deposits

Lithology: alluvium; mass wasting; dune sand; lake or marine deposit (non-glacial)

Tertiary (4) sedimentary rocks in western Utah (Middle Miocene to Late Pliocene) at surface, covers < 0.1 % of this area

Lithology: coarse-grained mixed clastic; alluvium; pyroclastic; basalt; evaporite

Landslide deposits (Quaternary) at surface, covers 0.2 % of this area

LANDSLIDE DEPOSITS

Lithology: landslide; colluvium; sedimentary rock

Serpentinite (Late Devonian to Early Triassic) at surface, covers < 0.1 % of this area

SERPENTINITE (Paleozoic)-Mineral, northwestern Nye, and eastern Humboldt counties

Lithology: serpentinite

Andesite and related rocks of intermediate composition (Late Eocene to Middle Eocene) at surface, covers 0.8 % of this area

ANDESITE AND RELATED ROCKS OF INTERMEDIATE COMPOSITION-Flows and breccias

Lithology: andesite; latite

Oligocene volcanic rocks (Late Eocene to Oligocene) at surface, covers < 0.1 % of this area

Lithology: dacite; rhyolite; andesite; basalt

Tuffaceous sedimentary rocks (Early Oligocene to Early Miocene) at surface, covers 0.1 % of this area

TUFFACEOUS SEDIMENTARY ROCKS-Locally includes minor amounts of tuff

Lithology: sandstone; siltstone; limestone; conglomerate; mudstone; debris flow; landslide; tuff

Playa, marsh, and alluvial-flat deposits, locally eroded (Quaternary) at surface, covers 5 % of this area

PLAYA, MARSH, AND ALLUVIAL-FLAT DEPOSITS, LOCALLY ERODED

Lithology: playa; alluvium

Granitic rocks (Paleocene to Late Miocene) at surface, covers 0.1 % of this area

GRANITIC ROCKS-Mostly quartz monzonite and granodiorite

Lithology: granodiorite; quartz monzonite; granite; monzonite

Older alluvial deposits (Miocene to Quaternary) at surface, covers 1 % of this area

OLDER ALLUVIAL DEPOSITS

Lithology: alluvium; lake or marine deposit (non-glacial)

Dune sand (Holocene) (Holocene) at surface, covers < 0.1 % of this area

Large areas of windblown sand composed of rock-forming minerals, mostly feldspar and small amounts of quartz, and, in southeastern Oregon, also pumice

Lithology: sand

Shale and chert (Silurian) at surface, covers < 0.1 % of this area

SHALE AND CHERT-Includes Fourmile Canyon Formation in Eureka County and Noh Formation of Riva (1970) and unnamed rocks in Elko County.

Lithology: shale; siltstone; chert; sandstone; limestone

Shale, siltstone, sandstone, chert-pebble conglomerate, and limestone (Devonian to Mississippian) at surface, covers 1 % of this area

SHALE, SILTSTONE, SANDSTONE, CHERT-PEBBLE CONGLOMERATE, AND LIMESTONE-Includes units such as Pilot Shale, Joana Limestone, Chainman Shale, and Diamond Peak Formation in northern and eastern Nevada and Narrow Canyon Limestone, Mercury Limestone, and Eleana Formation in southern Nevada

Lithology: shale; limestone; siltstone; sandstone; conglomerate; dolostone (dolomite); chert; quartzite

Continental sedimentary rocks (Late Cretaceous to Eocene) at surface, covers < 0.1 % of this area

CONTINENTAL SEDIMENTARY ROCKS-Includes units such as Pansy Lee Conglomerate in Humboldt County, part of Cretaceous(?) and Tertiary rocks of Kleinhampl and Ziony (1967) in northern Nye County, and part of "older clastic rocks" of Tschanz and Pampeyan (1970) in Lincoln County

Lithology: conglomerate; sandstone; siltstone; mudstone; limestone

Rhyolitic flows and shallow intrusive rocks (Late Eocene to Middle Eocene) at surface, covers 0.6 % of this area

RHYOLITIC FLOWS AND SHALLOW INTRUSIVE ROCKS

Lithology: rhyolite; dacite; trachyte

Massive limestone (Mississippian) at surface, covers < 0.1 % of this area

MASSIVE LIMESTONE-In the San Antonio Mountains, western Nye County

Lithology: limestone; conglomerate; sandstone; argillite

Havallah sequence of Silberling and Roberts (1962) (Mississippian to Permian) at surface, covers 0.6 % of this area

HAVALLAH SEQUENCE OF SILBERLING AND ROBERTS (1962)-Chert, argillite, shale, greenstone, and minor amounts of siltstone, sandstone, conglomerate, and limestone. Includes Schoonover Formation of Fagan (1962) and Reservation Hill Formation in Elko County, Farrel Canyon Formation in southwestern Humboldt County, Havallah and Pumpernickel Formations in Pershing, Lander, and parts of Humboldt Counties, and rocks originally considered a part of the Pablo and Excelsior Formations in northern Nye, northern Esmeralda, and southern Mineral Counties. Assignment of some rocks to the Havallah sequence in the East Range, Pershing County, is highly uncertain. Includes rocks ranging in age from Late Mississippian to Early Permian

Lithology: shale; metavolcanic rock; chert; siltstone; sandstone; conglomerate; limestone

Shale, chert, and minor amounts of quartzite, greenstone, and limestone (Ordovician) at surface, covers 0.6 % of this area

SHALE, CHERT, AND MINOR AMOUNTS OF QUARTZITE, GREENSTONE, AND LIMESTONE-Includes units such as Vinini Formation of north-central Nevada, Palmetto Formation in southern and central parts of Esmeralda County, and Comus Formation in Humboldt County. Locally includes rocks of Silurian and Devonian age.

Lithology: chert; shale; limestone; quartzite; andesite; siltstone; sandstone; chemical; greenstone; dolostone (dolomite)

Shale, mudstone, siltstone, sandstone, and carbonate rock; sparse volcanic rock (Late Triassic to Early Jurassic) at surface, covers 1 % of this area

SHALE, MUDSTONE, SILTSTONE, SANDSTONE, AND CARBONATE ROCK; SPARSE VOLCANIC ROCK (Upper Triassic and Lower Jurassic)-Includes Auld Lang Syne Group, Nightingale sequence of Bonham (1969), and Gabbs and Sunrise Formations

Lithology: claystone; shale; sandstone; siltstone; carbonate; volcanic rock (aphanitic); conglomerate

Rhyolitic flows and shallow intrusive rocks (Early Oligocene to Early Miocene) at surface, covers 0.5 % of this area

RHYOLITIC FLOWS AND SHALLOW INTRUSIVE ROCKS

Lithology: rhyolite; dacite; trachyte

Ash-flow tuffs and tuffaceous sedimentary rocks (Middle Miocene to Late Miocene) at surface, covers 1.0 % of this area

ASH-FLOW TUFFS AND TUFFACEOUS SEDIMENTARY ROCKS

Lithology: ash-flow tuff; rhyolite; sandstone; dacite; trachyte

Middle Cambrian shale and carbonate rocks in western Utah (Middle Cambrian) at surface, covers < 0.1 % of this area

Lithology: limestone; shale; dolostone (dolomite); argillite

Limestone (Pennsylvanian) at surface, covers < 0.1 % of this area

LIMESTONE-Includes Ely Limestone (mostly Lower and Middle Pennsylvanian)

Lithology: limestone; chert

Shale, sandstone, volcanogenic clastic rocks, andesite, rhyolite, and locally thick carbonate units (Late Triassic to Early Cretaceous) at surface, covers 0.4 % of this area

SHALE, SANDSTONE, VOLCANOGENIC CLASTIC ROCKS, ANDESITE, RHYOLITE, AND LOCALLY THICK CARBONATE UNITS-Undivided sequence locally containing recognizable equivalents of the Luning and Dunlap Formations

Lithology: rhyolite; andesite; dacite; trachyte; argillite; shale; sandstone; siltstone; carbonate; basalt

Andesite and related rocks of intermediate composition (Late Miocene to Middle Miocene) at surface, covers 2 % of this area

ANDESITE AND RELATED ROCKS OF INTERMEDIATE COMPOSITION-Flows and breccias

Lithology: andesite; latite; trachyte; dacite

Granitic rocks, central and eastern Nevada (Jurassic to Miocene) at surface, covers < 0.1 % of this area

GRANITIC ROCKS, CENTRAL AND EASTERN NEVADA-Mostly quartz monzonite and granodiorite. Inconclusively dated or not dated radiometrically

Lithology: quartz monzonite; granodiorite; granite; peraluminous granite

Shale and thin-bedded or laminated limestone; also thinly interbedded limestone and chert (Middle Cambrian to Late Cambrian) at surface, covers 0.1 % of this area

SHALE AND THIN-BEDDED OR LAMINATED LIMESTONE; ALSO THINLY INTERBEDDED LIMESTONE AND CHERT-Includes units such as Preble and Emigrant Formations

Lithology: shale; limestone; chert; siltstone; quartzite; diorite; conglomerate

Alluvial deposits (Holocene) (Holocene) at surface, covers < 0.1 % of this area

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

Lithology: sand; gravel; silt; peat

Slaven Chert (Devonian) at surface, covers 0.1 % of this area

SLAVEN CHERT-Chert and sparse limy sandstone, siltstone, and limestone. Lander County

Lithology: chert; shale; siltstone; sandstone; limestone

Metamorphic rocks (Early Proterozoic) at surface, covers 0.3 % of this area

METAMORPHIC ROCKS-Gneiss and schist and lesser amounts of gneissic granite, pyroxenite, hornblendite, migmatite, pegmatite, and marble.

Lithology: gneiss; schist; marble; granite; pyroxenite; hornblendite; migmatite; pegmatite; amphibolite

Morainal deposits (Quaternary) at surface, covers < 0.1 % of this area

MORAINAL DEPOSITS

Lithology: glacial drift

Intrusive rocks of mafic and intermediate composition (Miocene to Quaternary) at surface, covers < 0.1 % of this area

INTRUSIVE ROCKS OF MAFIC AND INTERMEDIATE COMPOSITION

Lithology: andesite; rhyodacite; basalt; sedimentary rock

Antler Sequence of Silberling and Roberts (1962) (Pennsylvanian to Late Permian ) at surface, covers < 0.1 % of this area

ANTLER SEQUENCE OF SILBERLING AND ROBERTS (1962) (Middle Pennsylvanian to Early or Late Permian) (Guadalupian)-Conglomerate, sandy to conglomeratic limestone, limestone, sandstone, and calcareous shale. Thin detrital and carbonate sequence within main part of Antler orogenic belt. Includes units such as Sunflower Formation of Bushnell (1967) in Elko County, Battle Formation, Antler Peak Limestone, and Edna Mountain Formation in Lander and western Eureka Counties, and Wildcat Peak Formation in northern Nye County

Lithology: conglomerate; limestone; sandstone; siltstone; shale

Undivided pre-Cenozoic metavolcanic rocks, unit 2 (undivided) (Paleozoic(?) to Mesozoic(?)) at surface, covers < 0.1 % of this area

Undivided pre-Cenozoic metavolcanic rocks. Includes latite, dacite, tuff, and greenstone; commonly schistose.

Lithology: intermediate volcanic rock; mafic volcanic rock; felsic volcanic rock; greenstone; amphibolite; gabbro

Middle Miocene to Oligocene volcanic rocks (Oligocene to Middle Miocene) at surface, covers < 0.1 % of this area

Lava, tuff, fine-grained intrusive rock, and diverse pyroclastic rocks. These compositionally variable volcanic rocks include basalt, andesite, dacite, and rhyolite. Thick felsic volcanic sequences form prominent cliffs and range fronts in the Black (Mohave County), Superstition, Kofa, Eagletail, Galiuro, and Chiricahua Mountains. This unit includes regionally extensive ash-flow tuffs, such as the Peach Springs tuff of northwestern Arizona and the Apache Leap tuff east of Phoenix. Most volcanic rocks are 20-30 Ma in southeastern Arizona and 15 to 25 Ma in central and western Arizona, but this unit includes some late Eocene rocks near the New Mexico border in east-central Arizona. (11-38 Ma)

Lithology: dacite; rhyolite; andesite; basalt; porphyry; diorite; granite; granodiorite; latite; trachybasalt; trachyte; conglomerate; sandstone; sedimentary breccia; serpentinite

Quartzite and minor amounts of conglomerate, phyllitic siltstone, limestone, and dolomite (Late Proterozoic to Early Cambrian) at surface, covers 0.6 % of this area

QUARTZITE AND MINOR AMOUNTS OF CONGLOMERATE, PHYLLITIC SILTSTONE, LIMESTONE, AND DOLOMITE-Includes Prospect Mountain Quartzite, Osgood Mountain Quartzite, and Gold Hill Formation in northern Nevada, and Stirling Quartzite, Wood Canyon Formation, and Zabriskie Quartzite in southern Nevada.

Lithology: quartzite; siltstone; dolostone (dolomite); limestone; phyllite; shale; conglomerate; sandstone

Mesozoic granitic rocks, unit 3 (Sierra Nevada, Death Valley area, Northern Mojave Desert and Transverse Ranges) (Permian to Tertiary; most Mesozoic) at surface, covers < 0.1 % of this area

Mesozoic granite, quartz monzonite, granodiorite, and quartz diorite

Lithology: granodiorite; quartz monzonite; tonalite; quartz diorite; diorite; granite; monzodiorite; quartz syenite; quartz monzodiorite; gabbro; trondhjemite; alkali-granite (alaskite); pegmatite; monzonite; aplite

Basalt flows (Late Miocene to Middle Miocene) at surface, covers 2 % of this area

BASALT FLOWS

Lithology: basalt

Volcanogenic sedimentary rocks, tuff, andesite and felsitic flows, and carbonate rocks (Permian to Jurassic (?)) at surface, covers < 0.1 % of this area

VOLCANOGENIC SEDIMENTARY ROCKS, TUFF, ANDESITIC AND FELSITIC FLOWS, AND CARBONATE ROCKS-Age uncertain. Mineral, Esmeralda, and Northwest Nye Counties

Lithology: greenstone ; sandstone; volcanic rock (aphanitic); limestone; siltstone; conglomerate

Volcanic sandstone, felsic ash-flow tuffs, rhyolite, and rhyodacite flows (Middle Jurassic to Early Cretaceous) at surface, covers < 0.1 % of this area

VOLCANIC SANDSTONE, FELSIC ASH-FLOW TUFFS, RHYOLITE, AND RHYODACITE FLOWS (Upper? Jurassic)-Pony Trail Group of Cortez Mountains, Eureka County

Lithology: quartz latite; ash-flow tuff; rhyolite; wacke; rhyodacite

Harmony Formation (Late Cambrian) at surface, covers 0.1 % of this area

HARMONY FORMATION (Upper Cambrian)-Feldspathic and arkosic sandstone and minor amounts of shale, limestone, and chert.

Lithology: sandstone; shale; limestone; chert; conglomerate

Pliocene and Quaternary alluvial material (Pliocene to Quaternary) at surface, covers < 0.1 % of this area

Lithology: alluvium

Chinle Formation (Late Triassic) at surface, covers < 0.1 % of this area

Colorful mudstone, such as in the Painted Desert, and less abundant lenses of sandstone and conglomerate, deposited by a large river system. This unit typically is eroded into badlands topography and contains clays that are prone to shrinking and swelling. (210-230 Ma)

Lithology: mudstone; sandstone; calcarenite; conglomerate; limestone; siltstone

Moenkopi Formation (Early and Middle(?) Triassic) at surface, covers < 0.1 % of this area

Dark red sandstone and mudstone; includes gypsum beds in northwestern Arizona; deposited on a low-relief coastal plain. (230-245 Ma)

Lithology: mudstone; sandstone; orthoquartzite; siltstone; arenite; claystone; conglomerate; dolostone (dolomite); gypsum; limestone; sedimentary breccia

Dolomite and limestone (Middle Cambrian to Ordovician) at surface, covers < 0.1 % of this area

DOLOMITE AND LIMESTONE-Undivided Cambrian and Ordovician rocks in part of Clark County; mostly Cambrian.

Lithology: dolostone (dolomite); limestone; shale

Quaternary alluvium and marine deposits (Pliocene to Holocene) at surface, covers < 0.1 % of this area

Alluvium, lake, playa, and terrace deposits; unconsolidated and semi-consolidated. Mostly nonmarine, but includes marine deposits near the coast.

Lithology: alluvium; terrace; lake or marine deposit (non-glacial)

Quartzite, phyllitic siltstone, conglomerate, limestone, and dolomite (Late Proterozoic) at surface, covers 0.1 % of this area

QUARTZITE, PHYLLITIC SILTSTONE, CONGLOMERATE, LIMESTONE, AND DOLOMITE-Includes McCoy Creek Group (excluding Stella Lake Quartzite) in east-central Nevada and Johnnie Formation in southern Nevada.

Lithology: quartzite; shale; conglomerate; siltstone; dolostone (dolomite)

Limestone and sparse dolomite, siltstone, and sandstone (Mississippian to Early Permian) at surface, covers 1 % of this area

LIMESTONE AND SPARSE DOLOMITE, SILTSTONE, AND SANDSTONE-Includes units such as undivided Riepe Spring Limestone of Steele (1960) and Ely Limestone or their equivalent in Elko, White Pine, and northern Lincoln Counties and most of the Bird Spring Formation and Callville Limestone in Clark and southern Lincoln Counties. Includes some stratigraphically higher Permian rocks in Leppy Peak, easternmost Elko County.

Lithology: limestone; sandstone; siltstone; chert; shale; dolostone (dolomite); conglomerate

Early Pleistocene to latest Pliocene surficial deposits (Late Pliocene to Early Pleistocene) at surface, covers < 0.1 % of this area

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)

Lithology: gravel; sand; mud; silt

Scott Canyon Formation (Early Cambrian to Middle Cambrian) at surface, covers < 0.1 % of this area

SCOTT CANYON FORMATION (Lower or Middle Cambrian)-Chert, shale, greenstone, and sparse limestone and quartzite. Southeast Humboldt County and northwest Lander County.

Lithology: chert; shale; greenstone; limestone; quartzite; sandstone

Olivine basalt (Pliocene and Miocene) (Miocene to Pliocene) at surface, covers < 0.1 % of this area

Thin, commonly open-textured (diktytaxitic), subophitic to intergranular olivine basalt flows, intercalated with and grades laterally through palagonite breccia and tuff into tuffaceous sedimentary rocks (unit Ts). In places includes flows of platy olivine andesite or basaltic andesite. Several potassium-argon ages ranging from about 4 to 7 Ma indicate unit is mostly of early Pliocene and late Miocene age. Includes Shumuray Ranch Basalt and Antelope Flat Basalt of Kittleman and others (1965), Grassy Mountain Basalt of Corcoran and others (1962), Drinkwater Basalt of Bowen and others (1963), basalt formerly assigned to Danforth Formation by Piper and others (1939) (see Walker, 1979), Hayes Butte Basalt of Hampton (1964), Pliocene and upper Miocene basalt flows capping and interstratified with the Madras (or Deschutes) Formation, and basalt flows interstratified in the Dalles Formation of Newcomb (1966; 1969)

Lithology: basalt; andesite

Limestone, dolomite, and shale (Mississippian to Permian) at surface, covers 0.2 % of this area

LIMESTONE, DOLOMITE, AND SHALE (Upper Paleozoic)-Includes Van Duzer Limestone of Decker (1962)

Lithology: limestone; shale; sandstone; quartzite; siltstone; chert; conglomerate

Devonian marine rocks, unit 1 (Death Valley) (Middle to Late Devonian) at surface, covers < 0.1 % of this area

Limestone and dolomite, sandstone and shale; in part tuffaceous

Lithology: limestone; dolostone (dolomite); sandstone; marble; quartzite

Pliocene to middle Miocene deposits (Middle Miocene to Pliocene) at surface, covers < 0.1 % of this area

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)

Lithology: conglomerate; sandstone; gravel; sand; gypsum; limestone; mudstone; siltstone

Gabbroic complex (Early Jurassic to Middle Jurassic) at surface, covers < 0.1 % of this area

GABBROIC COMPLEX (Lower and Middle Jurassic)-Includes gabbro, basalt, and synorogenic quartz sandstone (Boyer Ranch Formation). Churchill and Pershing Counties

Lithology: gabbro; basalt; arenite; conglomerate; limestone

Tertiary volcanic flow rocks, unit 17 (Cascade Range) (Tertiary (2-24 Ma)) at surface, covers < 0.1 % of this area

Tertiary volcanic flow rocks; minor pyroclastic deposits.

Lithology: andesite; basalt; rhyolite; dacite; volcanic breccia (agglomerate)

Silurian carbonate rocks in western Utah (Silurian) at surface, covers < 0.1 % of this area

Lithology: dolostone (dolomite); chert

Basalt flows, pyroclastic debris, clastic sediments, and diatomite; Pliocene basaltic volcanics and clastic sediments; Snake River Plain and vicinity (Pliocene) at surface, covers < 0.1 % of this area

Pliocene olivine basalt flows and associated tuff and detritus of southern Idaho.

Lithology: basalt; lava flow; tuff; mixed clastic/volcanic

Quaternary volcanic flow rocks, unit 1 (Cascade Volcanic Field) (Quaternary) at surface, covers < 0.1 % of this area

Quaternary volcanic flow rocks; minor pyroclastic deposits; in part Pliocene and Miocene.

Lithology: andesite; basalt; rhyolite; dacite; volcanic breccia (agglomerate)

Early Proterozoic metamorphic rocks (Early Proterozoic) at surface, covers < 0.1 % of this area

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

Lithology: schist; gneiss; amphibolite; granofels; calc-silicate schist; granulite; greenschist; marble; diorite; gabbro; granite; granodiorite; metasedimentary rock; migmatite; phyllite; quartzite

Siliceous and volcanic rocks (Mississippian) at surface, covers < 0.1 % of this area

SILICEOUS AND VOLCANIC ROCKS-In Humboldt County, consists of altered pillow lavas, coarse volcanic breccias, clastic limestone, and minor amounts of sandstone, shale, siliceous shale, and chert of the Goughs Canyon Formation (Lower and Upper Mississippian). In the East Range, Pershing County, consists of quartzite, conglomerate, slate, limestone, chert, and greenstone of the Inskip Formation (Mississippian?).

Lithology: metavolcanic rock; sandstone; siltstone; limestone; shale; chert; conglomerate; quartzite

Late to middle Miocene basaltic rocks (Middle to Late Miocene) at surface, covers < 0.1 % of this area

Mostly dark, mesa-forming basalt deposited as lava flows. Rocks of this unit are widely exposed south of Camp Verde (Hickey Formation basalts), in the Mohon Mountains north of Bagdad, "The Mesa" east of Parker, and at other scattered locations in western Arizona. Rocks of this unit were not tilted by middle-Tertiary normal faulting except in a narrow belt from north of Phoenix to the northwest corner of the state. (8-16 Ma)

Lithology: basalt; alkaline basalt; hawaiite; tholeiite; andesite; dacite; rhyolite; trachyandesite; trachybasalt; conglomerate; sandstone; sedimentary breccia

Siliceous and volcanic rocks (Ordovician to Devonian) at surface, covers 0.7 % of this area

SILICEOUS AND VOLCANIC ROCKS-Chert, shale, quartzite, greenstone, and minor amounts of limestone. Includes units such as Valmy Formation of north-central Nevada and some rocks mapped as Palmetto Formation in northern part of Esmeralda County and adjacent parts of Mineral and Nye Counties. Locally includes rocks of Silurian and Devonian age.

Lithology: chert; quartzite; shale; greenstone; limestone; conglomerate; siltstone; chemical

Chinle Formation and associated rocks (Late Triassic) at surface, covers < 0.1 % of this area

CHINLE FORMATION AND ASSOCIATED ROCKS (Upper Triassic)-Continental deposits of variegated bentonitic claystone, siltstone, and clayey sandstone; ledge-forming sandstone; and red siltstone

Lithology: claystone; siltstone; sandstone; gypsum; conglomerate; limestone

Tertiary nonmarine rocks, undivided (Paleocene to Pliocene) at surface, covers < 0.1 % of this area

Undivided Tertiary sandstone, shale, conglomerate, breccia, and ancient lake deposits.

Lithology: conglomerate; sandstone; sedimentary breccia; volcanic rock (aphanitic); mudstone; limestone; siltstone

Welded and nonwelded silicic ash-flow tuffs (Late Eocene to Middle Eocene) at surface, covers 0.6 % of this area

WELDED AND NONWELDED SILICIC ASH-FLOW TUFFS-Locally includes thin units of air-fall tuff and sedimentary rock

Lithology: rhyolite; dacite; trachyte

Horse Spring Formation (Late Oligocene to Middle Miocene) at surface, covers < 0.1 % of this area

HORSE SPRING FORMATION-Tuffaceous sedimentary rocks, southern Nevada

Lithology: limestone; sandstone; dolostone (dolomite); mudstone; siltstone; evaporite; tuff; lava flow; felsic volcanic rock; intermediate volcanic rock; mafic volcanic rock

Ash-flow tuffs, rhyolitic flows, and shallow intrusive rocks (Middle Miocene to Late Miocene) at surface, covers 0.1 % of this area

ASH-FLOW TUFFS, RHYOLITIC FLOWS, AND SHALLOW INTRUSIVE ROCKS

Lithology: rhyolite; dacite; trachyte

Moenkopi Formation, Thaynes Formation, and related rocks (Early Triassic to Middle Triassic) at surface, covers 0.2 % of this area

MOENKOPI FORMATION, THAYNES FORMATION, AND RELATED ROCKS (Lower Triassic)-Marine deposits of siltstone, limestone, and sparse conglomerate

Lithology: shale; limestone; siltstone; sandstone; gypsum; dolostone (dolomite); conglomerate

Conglomerate, sandstone, shale, and dolomite of Diablo Formation below and shale, sandstone, and conglomerate of Candelaria Formation above (Early Permian to Early Triassic) at surface, covers < 0.1 % of this area

CONGLOMERATE, SANDSTONE, SHALE, AND DOLOMITE OF DIABLO FORMATION BELOW AND SHALE, SANDSTONE, AND CONGLOMERATE OF CANDELARIA FORMATION ABOVE (Lower or Upper Permian to Lower Triassic)-Mineral, Esmeralda, and northwestern Nye Counties

Lithology: shale; siltstone; sandstone; dolostone (dolomite); limestone; conglomerate

Limestone and minor amounts of dolomite and shale (Mississippian) at surface, covers 0.2 % of this area

LIMESTONE AND MINOR AMOUNTS OF DOLOMITE AND SHALE-Includes units such as Rogers Spring and Monte Cristo Limestones

Lithology: limestone; dolostone (dolomite); chert; shale; sandstone

Dolomite and limestone (Middle Cambrian to Devonian) at surface, covers 0.2 % of this area

DOLOMITE AND LIMESTONE (Lower Paleozoic)

Lithology: marble; dolostone (dolomite); limestone; chert; quartzite

Platy limestone and limy siltstone, chert at base (Silurian to Early Devonian) at surface, covers < 0.1 % of this area

PLATY LIMESTONE AND LIMY SILTSTONE, CHERT AT BASE-Includes units such as Roberts Mountains Formation, and Storff Formation and Chellis Limestone of Decker (1962). Locally includes rocks of Early Devonian age at top.

Lithology: limestone; dolostone (dolomite); chert; siltstone; shale

Holocene surficial deposits (Holocene) at surface, covers < 0.1 % of this area

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)

Lithology: sand; gravel; mud; silt

Limestone, cherty limestone, sandy limestone, and chert-pebble conglomerate (Pennsylvanian) at surface, covers < 0.1 % of this area

LIMESTONE, CHERTY LIMESTONE, SANDY LIMESTONE, AND CHERT-PEBBLE CONGLOMERATE (Lower and Middle Pennsylvanian)-Includes units such as Moleen and Tomera Formations of Dott (1955)

Lithology: limestone; conglomerate

Shale, siliceous siltstone, chert, and minor amounts of limestone (Devonian) at surface, covers < 0.1 % of this area

SHALE, SILICEOUS SILTSTONE, CHERT, AND MINOR AMOUNTS OF LIMESTONE-Includes Cockalorum Wash Formation of northern Nye County and Woodruff Formation and unnamed rocks in Elko County

Lithology: shale; chert; limestone; siltstone; dolostone (dolomite); sandstone

Dolomite (Silurian to Early Devonian) at surface, covers 0.2 % of this area

DOLOMITE-Includes units such as Laketown and Lone Mountain Dolomites. Locally includes rocks of Early Devonian age at top.

Lithology: dolostone (dolomite); limestone; chert; sedimentary breccia

Quaternary alluvium and colluvium (Quaternary) at surface, covers < 0.1 % of this area

Lithology: alluvium; colluvium

Cherty limestone and sparse dolomite, shale, and sandstone (Permian) at surface, covers 0.5 % of this area

CHERTY LIMESTONE AND SPARSE DOLOMITE, SHALE, AND SANDSTONE (Lower and Upper Permian)-Includes units such as Park City Group and equivalent rocks in northern Nevada and Toroweap Formation and Kaibab Limestone in southern Nevada

Lithology: limestone; shale; dolostone (dolomite); sandstone; siltstone; chert; conglomerate; phosphorite; evaporite

Siltstone, shale, and limestone; Early Triassic marine to non-marine epicontinental deposits; southeastern Idaho (Early Triassic) at surface, covers < 0.1 % of this area

Lower Triassic shallow-marine to non-marine sediments; limestone and chert above shaley sandstone, siltstone, and limestone of eastern Idaho.

Lithology: siltstone; shale; limetstone; chert; dolostone (dolomite)

Volcanic flows and flow breccias, chiefly of andesitic composition, tuffs, sparse sandstone and graywacke (Permian to Jurassic) at surface, covers 0.2 % of this area

VOLCANIC FLOWS AND FLOW BRECCIAS, CHIEFLY OF ANDESITIC COMPOSITION, TUFFS, SPARSE SANDSTONE AND GRAYWACKE-Includes Happy Creek Volcanic Series and related rocks in Humboldt County and similar rocks in Washoe and Pershing Counties; includes andesite breccias and volcanogenic sedimentary rocks in Mineral County

Lithology: andesite; basalt; dacite; graywacke; sandstone; shale; chert; limestone; conglomerate

Ordovician sedimentary rocks in western Utah (Ordovician) at surface, covers < 0.1 % of this area

Lithology: limestone; fine-grained mixed clastic; sandstone; dolostone (dolomite)

Cambrian quartzite in western Utah (Early Cambrian) at surface, covers < 0.1 % of this area

Lithology: arenite; conglomerate

Early Pleistocene to late Miocene basin deposits (Late Pliocene to Early Pleistocene) at surface, covers < 0.1 % of this area

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)

Lithology: gravel; sand; mud; silt

Sandstone and quartzite (Cambrian) at surface, covers < 0.1 % of this area

SANDSTONE AND QUARTZITE-Includes Tapeats Sandstone and related rocks. Rests on Precambrian metamorphic rocks.

Lithology: sandstone; quartzite; shale

Tuffaceous sedimentary rocks and tuff (Pliocene and Miocene) (Miocene to Pliocene) at surface, covers < 0.1 % of this area

Semiconsolidated to well-consolidated mostly lacustrine tuffaceous sandstone, siltstone, mudstone, concretionary claystone, conglomerate, pumicite, diatomite, air-fall and water-deposited vitric ash, palagonitic tuff and tuff breccia, and fluvial sandstone and conglomerate. Palagonitic tuff and breccia grade laterally into altered and unaltered basalt flows of unit Tob. In places includes layers of fluvial conglomerate and, in parts of the Deschutes-Umatilla Plateau, extensive deposits of fanglomerate composed mostly of Miocene basalt debris and silt. Also includes thin, welded and nonwelded ash-flow tuffs. Vertebrate and plant fossils indicate rocks of unit are mostly of Clarendonian and Hemphillian (late Miocene and Pliocene) age. Potassium-argon ages on interbedded basalt flows and ash-flow tuffs range from about 4 to 10 Ma. Includes the Drewsey Formation of Shotwell and others (1963); sedimentary parts of the Rattlesnake Formation of Brown and Thayer (1966); an interstratified ash-flow tuff has been radiometrically dated by potassium-argon methods at about 6.6 Ma (see Fiebelkorn and others, 1983); Bully Creek Formation of Kittleman and others (1967); Dalles Formation of Newcomb (1966, 1969); Shutler Formation of Hodge (1932), McKay beds of Hogenson (1964) and Newcomb (1966) (see also Shotwell, 1956); Kern Basin Formation of Corcoran and others (1962); Rome beds of Baldwin (1976); parts of the (now obsolete) Danforth Formation of Piper and others (1939), Idaho Group of Malde and Powers (1962), Thousand Creek Beds of Merriam (1910); the Madras (or Deschutes) Formation, the "Simtustus formation" of Smith (1984), and the Yonna Formation (Newcomb, 1958). In areas west of Cascade crest, includes the Sandy River Mudstone and the Troutdale Formation of Trimble (1963) and the lower Pliocene Helvetia Formation of Schlicker and Deacon (1967)

Lithology: sandstone; siltstone; mudstone; conglomerate; pumice; diatomite; tuff; conglomerate

Dunlap Formation (Early Jurassic to Middle Jurassic) at surface, covers < 0.1 % of this area

DUNLAP FORMATION (Lower and Middle Jurassic)-Conglomerate, sandstone, greenstone, felsite, and tuff. Locally contemporaneous with folding and thrusting. Mineral County and adjacent parts of Esmeralda and Nye Counties

Lithology: sandstone; conglomerate; volcanic rock (aphanitic); limestone; siltstone; shale

Sandy and silty limestone, conglomerate, and siltstone (Pennsylvanian to Late Permian) at surface, covers 0.2 % of this area

SANDY AND SILTY LIMESTONE, CONGLOMERATE, AND SILTSTONE (Upper Pennsylvanian to Upper Permian)-Includes units such as Strathearn Formation of Dott (1955) and Buckskin Mountain, Beacon Flat, and Carlin Canyon Formations of Dott (1955)

Lithology: limestone; conglomerate; siltstone; sandstone; chert

Younger Precambrian metamorphic rocks in western Utah (Precambrian) at surface, covers < 0.1 % of this area

Lithology: conglomerate; metamorphic rock

Elder Sandstone (Silurian) at surface, covers < 0.1 % of this area

ELDER SANDSTONE-Feldspathic sandstone, siltstone, shale, and chert. Lander County.

Lithology: arkose; siltstone; shale; chert

Tertiary intrusive rocks in western Utah (Late Eocene to Early Miocene) at surface, covers < 0.1 % of this area

Lithology: granodiorite; granite; quartz monzonite; quartz diorite

Mesozoic volcanic rocks, unit 5 (Northern Sierra Nevada and Eastern Klamath Mountains) (Late Permian(?) to Jurassic) at surface, covers < 0.1 % of this area

Undivided Mesozoic volcanic and metavolcanic rocks. Andesite and rhyolite flow rocks, greenstone, volcanic breccia and other pyroclastic rocks; in part strongly metamorphosed. Includes volcanic rocks of Franciscan Complex: basaltic pillow lava, diabase, greenstone, and minor pyroclastic rocks

Lithology: intermediate volcanic rock; felsic volcanic rock; clastic

Banbury Formation (Middle Miocene to Late Miocene) at surface, covers 1 % of this area

BANBURY FORMATION-Basalt, gravel, and tuffaceous sediments locally. Northeast Humboldt County and northwest Elko County

Lithology: basalt; gravel; sandstone

Limestone, sandstone, dolostone, and chert; Permian to Pennsylvanian marine epicontinental-basin deposits; southeastern Idaho; (Early Permian to Early Pennsylvanian) at surface, covers < 0.1 % of this area

Lower Permian to Lower Pennsylvanian chert, limestone, and sandstone of southern Idaho; subdivisions are (Ps, and PNs).

Lithology: limestone; sandstone; dolostone (dolomite); chert; siltstone; shale

Permian to Pennsylvanian sedimentary rocks (Pennsylvanian to Permian) at surface, covers < 0.1 % of this area

Interbedded sandstone, shale, and limestone usually characterized by ledgy outcrops. Orange to reddish sandstone forms cliffs near Sedona. This unit includes Supai Group and Hermit Shale in northern Arizona and Naco Group in southern Arizona. It was deposited in coastal-plain to shallow-marine settings during time of variable and changing sea level. Rocks of this map unit in southern Arizona may be in part equivalent to Permian rocks of map unit P in central and northern Arizona. (280-310 Ma)

Lithology: sandstone; siltstone; gypsum; mudstone; orthoquartzite; siltstone; sedimentary breccia; dolostone (dolomite); limestone; conglomerate; shale; calcarenite; evaporite

Silicic vent rocks (Pliocene, Miocene, Oligocene, and Eocene?) (Eocene to Pliocene) at surface, covers < 0.1 % of this area

Plugs and domal complexes of rhyolitic, rhyodacitic, and dacitic composition; includes related near-vent flows, flow breccia, and deposits of obsidian, perlite, and pumice. Locally includes resurgent domes related to caldera complexes. In southeast Oregon many domal complexes younger than 11 Ma exhibit a well-defined southeast to northwest age progression (Walker, 1974; MacLeod and others, 1976) from about 11 Ma to less than 1 Ma

Lithology: rhyolite; latite; dacite

Aztec Sandstone (Early Jurassic) at surface, covers < 0.1 % of this area

AZTEC SANDSTONE (Triassic? And Jurassic)-Friable fine- to medium-grained sandstone with conspicuous large-scale cross strata; considered eolian. Age based on correlation with Navajo Sandstone

Lithology: sandstone

Plio-Pleistocene and Pliocene loosely consolidated deposits (Miocene to Pleistocene) at surface, covers < 0.1 % of this area

Pliocene and/or Pleistocene sandstone, shale, and gravel deposits; in part Miocene.

Lithology: sandstone; conglomerate; claystone; shale; siltstone; limestone; evaporite; coal; sedimentary breccia

Tertiary volcanic flow rocks, unit 18 (San Joaquin-Kings Canyon) (Tertiary (3-4 Ma)) at surface, covers < 0.1 % of this area

Tertiary volcanic flow rocks; minor pyroclastic deposits.

Lithology: tephrite (basanite); trachybasalt; trachyandesite; trachyte

Playa deposits (Holocene) (Holocene) at surface, covers < 0.1 % of this area

Clay, silt, sand, and some evaporites

Lithology: clay or mud; silt; sand; evaporite

Miocene rhyolites (Middle to Late Miocene) at surface, covers < 0.1 % of this area

Lithology: rhyolite; dacite

Tertiary volcanic rocks, undivided (Tertiary) at surface, covers < 0.1 % of this area

Lithology: volcanic rock (aphanitic)

Igneous and metamorphic complex (Paleozoic sedimentary rocks with Mesozoic intrusive rocks) at surface, covers 0.3 % of this area

IGNEOUS AND METAMORPHIC COMPLEX-Pegmatitic granite and other granitic rocks complexly intermixed with metasedimentary rocks. Considered to be Mesozoic igneous complex intruding lower Paleozoic and possibly Precambrian Z sedimentary rocks. Grades into units shown on map as lower Paleozoic. Ruby Mountains and East Humboldt Range, Elko County

Lithology: marble; schist; gneiss; quartzite; granulite; dolostone (dolomite); granite; pegmatite

Quaternary surficial deposits, undivided (Quaternary) at surface, covers < 0.1 % of this area

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)

Lithology: sand; gravel; mud; silt

Intrusive rocks (Cretaceous and Jurassic) (Jurassic to Cretaceous) at surface, covers < 0.1 % of this area

Hornblende and biotite quartz diorite (tonalite), trondhjemite, granodiorite, and small amounts of norite, in batholithic masses and large dikelike bodies. Includes Bald Mountain Tonalite and Anthony Lake Granodiorite of Taubeneck (1957), tonalite and trondhjemite of Wallowa batholith and Cornucopia stock (Taubeneck, 1964; Nolf, 1966), quartz diorite intrusion in the Snake River area (Morrison, 1963), quartz diorite and minor other intrusive rocks in the Caviness quadrangle (Wolff, 1965), quartz diorite northeast of John Day and southeast of Ironside Mountain (Thayer and Brown, 1964), quartz diorite in the Sparta and Durkee quadrangles (Prostka, 1962; 1967), and granodiorite and related rocks of the Pueblo Mountains (Roback and others, 1987). Rubidium-strontium and potassium-argon ages indicate an age range from about 94 to 160 Ma (Taubeneck, 1963; Thayer and Brown, 1964; Armstrong and others, 1976)

Lithology: quartz diorite; trondhjemite; granodiorite

Terrace, pediment, and lag gravels (Holocene and Pleistocene) (Pleistocene to Holocene) at surface, covers < 0.1 % of this area

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)

Lithology: gravel; terrace; clay or mud; silt; sand

Phyllite, shale, and limestone (Middle Cambrian to Ordovician) at surface, covers 0.2 % of this area

PHYLLITE, SHALE, AND LIMESTONE-Locally includes chert and quartzite. Includes Tennessee Mountain Formation of Bushnell (1967) in western Elko County, Broad Canyon sequence of Means (1962) in Lander County, and rocks originally mapped as Palmetto Formation in Toiyabe and Toquima Ranges, northern Nye County

Lithology: shale; limestone; sandstone; chert

Basalt and andesite (Miocene) (Miocene) at surface, covers < 0.1 % of this area

Lava flows and breccia of aphyric and plagioclase porphyritic basalt and aphyric andesite; locally includes flow breccia, peperite, some palagonite tuff and breccia, and minor silicic ash-flow tuff and interbeds of tuffaceous sedimentary rocks. In Basin and Range and Owyhee Upland provinces unit grades upward into more silicic, andesitic, and quartz latitic flows and flow breccia, as well as some interbedded tuffs and ash-flow tuffs; also in this region includes aphyric and highly porphyritic, plagioclase-rich basalt. Interfingers with and grades laterally into units Tit and Tts. Commonly contains montmorillonite clays, zeolites, calcite, and secondary silica minerals as alteration products on fractures and in pore spaces. Age, mostly middle Miocene, but includes some rocks of early Miocene age based on vertebrate fossils from related sedimentary units and on potassium-argon ages that range from about 13 Ma to about 19 Ma; most isotopic ages are about 13 to 16 Ma. Includes Steens Basalt (Steens Mountain Basalt of Fuller, 1931) Owyhee Basalt of Corcoran and others (1962) and Kittleman and others (1967), Hunter Creek Basalt and "unnamed igneous complex" of Kittleman and others (1965, 1967), and flows of Prineville chemical type (Uppuluri, 1974; Swanson and others, 1979), which previously were considered part of the Columbia River Basalt Group (Swanson, 1969a)

Lithology: basalt ; andesite; tuff; ignimbrite; mixed clastic/volcanic

Sandstone, conglomerate, siltstone, tuff, claystone, limestone, and diatomite; Pliocene tuffaceous alluvial and lacustrine deposits; Snake River Plain and vicinity, southeastern Idaho (Pliocene ) at surface, covers < 0.1 % of this area

Pliocene stream and lake deposits; may be due to volcanic and block-faulting events.

Lithology: sandstone; conglomerate; siltstone; tuff; claystone; shale; limestone

Continental sedimentary rocks (Late Cretaceous to Early Miocene) at surface, covers 0.1 % of this area

CONTINENTAL SEDIMENTARY ROCKS-Clark County

Lithology: sandstone; conglomerate; siltstone; mudstone; limestone; felsic volcanic rock

Older Quaternary alluvial deposits (Quaternary) at surface, covers < 0.1 % of this area

Lithology: alluvium

Gravel, sand, and silt; Quaternary basin-filling alluvium; Snake River Plain, Basin and Range provinces (Quaternary) at surface, covers < 0.1 % of this area

Quaternary detritus; generally basin-filling deposits of central and southern Idaho.

Lithology: alluvium; alluvial fan; alluvial terrace

Holocene river alluvium (Holocene) at surface, covers < 0.1 % of this area

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)

Lithology: sand; gravel; mud; silt

Conglomerate, limestone, meta-andesite, phyllite, and shale (Devonian to Mississippian) at surface, covers < 0.1 % of this area

CONGLOMERATE, LIMESTONE, META-ANDESITE, PHYLLITE, AND SHALE-Includes Grossman, Banner, Nelson, and Mountain City Formation. Northern Elko County

Lithology: schist; metavolcanic rock; conglomerate; sandstone; siltstone; phyllite; limestone; diabase

Chert, shale, argillite, siltstone, quartzite, and greenstone (Cambrian to Devonian) at surface, covers < 0.1 % of this area

CHERT, SHALE, ARGILLITE, SILTSTONE, QUARTZITE, AND GREENSTONE-Undivided siliceous assemblage. Mostly Ordovician

Lithology: chert; quartzite; limestone; siltstone; conglomerate; shale

Shale, chert, and limestone (Ordovician) at surface, covers < 0.1 % of this area

SHALE, CHERT, AND LIMESTONE-Includes Aura Formation of Decker (1962) in northwest Elko County and Perkins Canyon Formation of Kay and Crawford (1964) in northern Nye County

Lithology: shale; chert; limestone; quartzite

Quaternary Lake Bonneville deposits (Quaternary) at surface, covers < 0.1 % of this area

Lithology: clay or mud; sand; gravel; silt

Middle Proterozoic granitic rocks (Middle Proterozoic) at surface, covers < 0.1 % of this area

Mostly porphyritic biotite granite with large microcline phenocrysts, with local fine-grained border phases and aplite. Associated pegmatite and quartz veins are rare. This unit forms large plutons, including the Oracle Granite, Ruin Granite, granite in the Pinnacle Peak - Carefree area northeast of Phoenix, and several bodies west of Prescott. (1400-1450 Ma)

Lithology: granite; granodiorite; quartz diorite; quartz monzonite; pegmatite; aplite

Permian (1) sedimentary rocks in western Utah (Early Permian) at surface, covers < 0.1 % of this area

Lithology: sandstone; carbonate; fine-grained mixed clastic; evaporite

Granitic rocks (Middle Proterozoic) at surface, covers < 0.1 % of this area

GRANITIC ROCKS-Porphyritic rapakivi granite.

Lithology: granite

Wyman Formation (Late Proterozoic) at surface, covers < 0.1 % of this area

WYMAN FORMATION-Phyllite and phyllitic siltstone and minor amounts of limestone, dolomite, and sandstone

Lithology: siltstone; limestone; sandstone; dolostone (dolomite)

Rhyolite, quartz latite, and latite ignimbrites and flows; Miocene felsic volcanics; Owyhee Plateau; (Miocene) at surface, covers < 0.1 % of this area

Miocene silicic flows, tuffs; most common in southwestern Idaho.

Lithology: rhyolite; latite; quartz latite; ignimbrite; lava flow

Pennsylvanian and Permian sedimentary rocks in southwestern Utah (Pennsylvanian) at surface, covers < 0.1 % of this area

Lithology: dolostone (dolomite); sandstone

Olivine basalt (Pliocene and Miocene) (Miocene to Pliocene) at surface, covers < 0.1 % of this area

Lithology: basalt; andesite

Quaternary mud and salt flats (Holocene) at surface, covers < 0.1 % of this area

Lithology: mud flat; playa

Precambrian rocks, undivided, unit 1 (Death Valley) (Early Proterozoic to Mesozoic) at surface, covers < 0.1 % of this area

Conglomerate, shale, sandstone, limestone, dolomite, marble, gneiss, hornfels, and quartzite; may be Paleozoic in part

Lithology: sandstone; mudstone; dolostone (dolomite); limestone; conglomerate; gneiss; granitoid; metavolcanic rock

Mississippian (1) carbonate rocks in western Utah (Mississippian) at surface, covers < 0.1 % of this area

Lithology: limestone

Tertiary pyroclastic and volcanic mudflow deposits, unit 8 (Northern Mojave Desert) (Tertiary (4-22 Ma)) at surface, covers < 0.1 % of this area

Tertiary pyroclastic and volcanic mudflow deposits.

Lithology: rhyolite; dacite; andesite; basalt; volcanic breccia (agglomerate); tuff; ash-flow tuff; ignimbrite

Leucogranite and rhyolite porphyry (Mississippian to Triassic) at surface, covers < 0.1 % of this area

LEUCOGRANITE AND RHYOLITE PORPHYRY

Lithology: granite; rhyolite

Silty limestone, minor amounts of shale, and some greenstone (Permian to Early Triassic) at surface, covers < 0.1 % of this area

SILTY LIMESTONE, MINOR AMOUNTS OF SHALE, AND SOME GREENSTONE-Unnamed sequence in Adobe Range, northern Elko County

Lithology: limestone; shale; greenstone

Welded tuffs and tuffaceous sedimentary rocks (upper? and middle Miocene) (Middle to Late Miocene) at surface, covers < 0.1 % of this area

Partly to densely welded vitric and vitric-crystal tuff of soda-rhyolitic, rhyolitic, and rhyodacitic composition that interfingers with and grades laterally into unit Tit. Includes some nonwelded ash-flow tuff and tuffaceous sedimentary rocks. Potassium-argon ages range from about 13 to 16 Ma. In Harney and Malheur Counties, it commonly overlies unit Tmb. Includes Dinner Creek Welded Tuff of Haddock (1965; 1967) and middle and upper Miocene ash-flow tuffs of Rytuba and others (1982; 1983a, b), widely exposed in the Trout Creek Mountains and adjacent areas, erupted from the McDermitt caldera complex, west and southwest of McDermitt, Nevada-Oregon, the White Horse caldera, northwest of McDermitt, and several other vent areas

Lithology: rhyolite; dacite; mudstone

Cambrian marine rocks (Late Proterozoic to Middle Devonian) at surface, covers < 0.1 % of this area

Sandstone, shale, limestone, dolomite, chert, quartzite, and phyllite; includes some rocks that are possibly Precambrian

Lithology: sandstone; dolostone (dolomite); mudstone; limestone; quartzite; conglomerate; chert

Accessibility FOIA Privacy Policies and Notices

U.S. Department of the Interior | U.S. Geological Survey
URL: http://mrdata.usgs.gov/geology/state/fips-unit.php?state=NV
Page Contact Information: pschweitzer@usgs.gov
Page Last modified: 10:03 on 08-May-2012