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Mineral Resources > Online Spatial Data > Geology > by state > California Geology

Geologic units in Mono county, California

[Additional scientific data in this geographic area]

pre-Cenozoic granitic and metamorphic rocks undivided (Early Proterozoic to Late Cretaceous) at surface, covers 0.4 % of this area

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

Lithology: plutonic rock (phaneritic); gneiss; metasedimentary rock; metavolcanic rock

Tertiary pyroclastic and volcanic mudflow deposits, unit 8 (Northern Mojave Desert) (Tertiary (4-22 Ma)) at surface, covers 0.3 % of this area

Tertiary pyroclastic and volcanic mudflow deposits.

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

Carboniferous marine rocks, unit 8 (Mono Lake) (Ordovician to Devonian) at surface, covers 0.5 % of this area

Shale, sandstone, conglomerate, limestone, dolomite, chert, hornfels, marble, quartzite; in part pyroclastic rocks

Lithology: argillite; chert; hornfels; sandstone

Paleozoic metavolcanic rocks, unit 5 (Mono Lake) (Triassic to Jurassic) at surface, covers 0.2 % of this area

Undivided Paleozoic metavolcanic rocks. Mostly flows, breccia and tuff, including greenstone, diabase, and pillow lavas; minor interbedded sedimentary rocks

Lithology: intermediate volcanic rock; felsic volcanic rock; mafic volcanic rock; sandstone; marble; conglomerate; shale

Quaternary volcanic flow rocks, unit 6 (Sierra Nevada) (Quaternary) at surface, covers 1.0 % of this area

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

Lithology: basalt; andesite

Cambrian marine rocks (Late Proterozoic to Middle Devonian) at surface, covers 2 % 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

Paleozoic marine rocks, undivided, unit 3 (Eastern Sierra Nevada) (Late Proterozoic(?) to Mesozoic(?)) at surface, covers 0.8 % of this area

Undivided Paleozoic metasedimentary rocks. Includes slate, sandstone, shale, chert, conglomerate, limestone, dolomite, marble, phyllite, schist, hornfels, and quartzite

Lithology: hornfels; quartzite; conglomerate; phyllite; schist; marble; chert; argillite; sandstone

Recent (Holocene) pyroclastic and volcanic mudflow deposits, unit 2 (Mono Craters) (Holocene) at surface, covers 2 % of this area

Recent (Holocene) pyroclastic and volcanic mudflow deposits; in part Pleistocene.

Lithology: rhyolite; pumice; cinders; volcanic mudflows

Triassic marine rocks, unit 7 (Mono Lake) (Paleozoic or Mesozoic) at surface, covers < 0.1 % of this area

Shale, conglomerate, limestone and dolomite, sandstone, slate, hornfels, quartzite; minor pyroclastic rocks

Lithology: hornfels; quartzite; chert

Phyllitc siltstone, quartzite, and lesser amounts of limestone and dolomite (Late Proterozoic to Early Cambrian) at surface, covers < 0.1 % 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

Precambrian rocks, undivided, unit 1 (Death Valley) (Early Proterozoic to Mesozoic) at surface, covers 0.8 % 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

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

LANDSLIDE DEPOSITS

Lithology: landslide; colluvium; sedimentary rock

Basalt flows (Miocene to Quaternary) at surface, covers < 0.1 % of this area

BASALT FLOWS-Locally includes maar deposits

Lithology: basalt; andesite; trachybasalt; latite; andesite

Permian marine sedimentary rocks, unit 1 (Death Valley and Mojave Desert) (Pennsylvanian to Triassic) at surface, covers 0.2 % of this area

Shale, conglomerate, limestone and dolomite, sandstone, slate, hornfels, quartzite; minor pyroclastic rocks

Lithology: limestone; sandstone; hornfels; conglomerate; marble; mudstone

Tuffaceous sedimentary rocks (Late Eocene to Late Miocene) at surface, covers < 0.1 % 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

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)

Tertiary intrusive rocks (hypabyssal), unit 1 (Cascades Volcanic Field) (Tertiary) at surface, covers 0.1 % of this area

Tertiary intrusive rocks; mostly shallow (hypabyssal) plugs and dikes. Includes some Mesozoic rocks.

Lithology: andesite; basalt; rhyolite; dacite

Quaternary alluvium and marine deposits (Pliocene to Holocene) at surface, covers 19 % 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)

Tertiary volcanic flow rocks, unit 18 (San Joaquin-Kings Canyon) (Tertiary (3-4 Ma)) at surface, covers 6 % of this area

Tertiary volcanic flow rocks; minor pyroclastic deposits.

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

Andesite and related rocks of intermediate composition (Late Miocene to Middle Miocene) at surface, covers < 0.1 % of this area

ANDESITE AND RELATED ROCKS OF INTERMEDIATE COMPOSITION-Flows and breccias

Lithology: andesite; latite; trachyte; dacite

Mesozoic granitic rocks, unit 3 (Sierra Nevada, Death Valley area, Northern Mojave Desert and Transverse Ranges) (Permian to Tertiary; most Mesozoic) at surface, covers 22 % 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

Shale, sandstone, volcanogenic clastic rocks, andesite, rhyolite, and locally thick carbonate units (Late Triassic to Early Cretaceous) at surface, covers < 0.1 % 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

Undivided pre-Cenozoic metavolcanic rocks, unit 2 (undivided) (Paleozoic(?) to Mesozoic(?)) at surface, covers 0.2 % 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

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

Carboniferous marine rocks, unit 7 (Bishop) (Mississippian to Early Permian) at surface, covers 0.2 % of this area

Shale, sandstone, conglomerate, limestone, dolomite, chert, hornfels, marble, quartzite; in part pyroclastic rocks

Lithology: hornfels; marble; conglomerate

Tertiary volcanic flow rocks, unit 17 (Cascade Range) (Tertiary (2-24 Ma)) at surface, covers 10 % of this area

Tertiary volcanic flow rocks; minor pyroclastic deposits.

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

pre-Cenozoic metasedimentary and metavolcanic rocks undivided (Early Proterozoic to Cretaceous) at surface, covers 0.5 % of this area

Undivided pre-Cenozoic metasedimentary and metavolcanic rocks of great variety. Mostly slate, quartzite, hornfels, chert, phyllite, mylonite, schist, gneiss, and minor marble.

Lithology: schist; gneiss; quartzite; argillite; phyllite; metavolcanic rock; slate; hornfels; marble; chert; sandstone; mudstone; conglomerate

Tertiary pyroclastic and volcanic mudflow deposits, unit 9 (Cascade Range) (Tertiary (2-24 Ma)) at surface, covers 4 % of this area

Tertiary pyroclastic and volcanic mudflow deposits.

Lithology: andesite; rhyolite; basalt; tuff; ash-flow tuff; ignimbrite

Quaternary pyroclastic and volcanic mudflow deposits, unit 2 (Long Valley Caldera) (Quaternary (0-1 Ma)) at surface, covers 9 % of this area

Quaternary pyroclastic and volcanic mudflow deposits.

Lithology: rhyolite; ash-flow tuff; ignimbrite

Welded and nonwelded silicic ash-flow tuffs (Middle Miocene to Late Miocene) at surface, covers < 0.1 % of this area

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

Lithology: rhyolite

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

GRANITIC ROCKS-Mostly quartz monzonite and granodiorite

Lithology: granodiorite; quartz monzonite; granite; peraluminous granite

Mesozoic volcanic rocks, unit 3 (Mojave Desert, Death Valley area, and Eastern Sierra Nevada) (Triassic to Cretaceous) at surface, covers 3 % 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: felsic volcanic rock; intermediate volcanic rock; basalt; clastic; limestone

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

GRANITIC ROCKS-Mostly quartz monzonite and granodiorite

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

Quaternary glacial deposits (Pleistocene) at surface, covers 6 % of this area

Glacial till and moraines. Found at high elevations mostly in the Sierra Nevada and Klamath Mountains.

Lithology: glacial drift

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

ALLUVIAL DEPOSITS-Locally includes beach and sand dune deposits

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

Triassic marine rocks, unit 4 (West Walker River) (Triassic(?)) at surface, covers < 0.1 % of this area

Shale, conglomerate, limestone and dolomite, sandstone, slate, hornfels, quartzite; minor pyroclastic rocks

Lithology: limestone; sandstone; mafic volcanic rock; felsic volcanic rock; mudstone; argillite; hornfels

Quaternary volcanic flow rocks, unit 2 (Long Valley Caldera) (Quaternary) at surface, covers 4 % of this area

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

Lithology: rhyolite; andesite; basalt

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

RHYOLITIC FLOWS AND SHALLOW INTRUSIVE ROCKS

Lithology: rhyolite; dacite; trachyte

Granitic rocks, western Nevada (Jurassic to Cretaceous) at surface, covers < 0.1 % 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

Playa, marsh, and alluvial-flat deposits, locally eroded (Quaternary) at surface, covers < 0.1 % of this area

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

Lithology: playa; alluvium

Schist of various types and ages, unit 11 (Benton Range) (Late Proterozoic(?) to Paleozoic(?)) at surface, covers < 0.1 % of this area

Schists of various types; mostly Paleozoic or Mesozoic age; some Precambrian.

Lithology: schist; hornfels

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

OLDER ALLUVIAL DEPOSITS

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

Mesozoic gabbroic rocks, unit 2 (undivided) (Triassic to Cretaceous) at surface, covers 0.2 % of this area

Gabbro and dark dioritic rocks; chiefly Mesozoic

Lithology: gabbro; diorite

Cretaceous marine rocks (in part nonmarine), unit 2 (West Walker River) (Triassic(?) and/or Jurassic(?)) at surface, covers 0.8 % of this area

Undivided Cretaceous sandstone, shale, and conglomerate; minor nonmarine rocks in Peninsular Ranges

Lithology: sandstone; mudstone; andesite; rhyolite; dacite; limestone; conglomerate

Silurian and/or Ordovician marine rocks, unit 2 (Bishop) (Late Cambrian(?) to Early Permian(?)) at surface, covers 1 % of this area

Sandstone, shale, conglomerate, chert, slate, quartzite, hornfels, marble, dolomite, phyllite; some greenstone

Lithology: argillite; sandstone; slate; hornfels; chert; quartzite; marble; conglomerate

Plio-Pleistocene and Pliocene loosely consolidated deposits (Miocene to Pleistocene) at surface, covers 0.4 % 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

Recent (Holocene) volcanic flow rocks, unit 2 (Mono Craters) (Holocene) at surface, covers 1 % of this area

Recent (Holocene) volcanic flow rocks; minor pyroclastic deposits; in part Pleistocene.

Lithology: rhyolite

Jurassic marine rocks, unit 6 (Mono Lake) (Ordovician(?) to Triassic(?)) at surface, covers 1.0 % of this area

Shale, sandstone, minor conglomerate, chert, slate, limestone; minor pyroclastic rocks

Lithology: hornfels; siltstone; marble; conglomerate; sandstone