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

Geologic units in San Bernardino county, California

[Additional scientific data in this geographic area]

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

Selected large landslides, such as Blackhawk slide on north side of San Gabriel Mountains; early to late Quaternary.

Lithology: landslide

Carboniferous marine rocks, unit 2 (SE California Carbonate Assemblage) (Mississippian to Early Permian) at surface, covers 0.1 % of this area

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

Lithology: limestone; mudstone; sandstone

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

Wide variety of granitic rocks, including granite, granodiorite, tonalite, quartz diorite, diorite, and gabbro. These rocks commonly are characterized by steep, northeast-striking foliation. (1600-1800 Ma)

Lithology: granodiorite; granite; diabase; diorite; gabbro; pegmatite; quartz diorite; tonalite; anorthosite; gneiss; gabbro; greisen; migmatite; porphyry; pyroxenite; rhyolite; schist; trondhjemite

Recent (Holocene) volcanic flow units, unit 4 (Mojave Desert) (Holocene) at surface, covers 0.5 % of this area

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

Lithology: tephrite (basanite); basalt

Limestone and minor amounts of dolomite and shale (Mississippian) at surface, covers < 0.1 % 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

Carboniferous marine rocks, unit 1 (Western Mojave Desert) (Late Proterozoic to Pennsylvanian) at surface, covers 0.3 % of this area

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

Lithology: marble; limestone; dolostone (dolomite); schist; quartzite; hornfels

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

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

Mesozoic granitic rocks, unit 3 (Sierra Nevada, Death Valley area, Northern Mojave Desert and Transverse Ranges) (Permian to Tertiary; most Mesozoic) at surface, covers 15 % 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

Quaternary alluvium and marine deposits (Pliocene to Holocene) at surface, covers 57 % 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)

pre-Cenozoic metasedimentary and metavolcanic rocks undivided (Early Proterozoic to Cretaceous) at surface, covers 0.9 % 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

Undated granitic rocks, unit 3 (Southern California) (Jurassic(?) to Cretaceous(?)) at surface, covers < 0.1 % of this area

Undated granitic rocks unit 3

Lithology: plutonic rock (phaneritic)

Tertiary volcanic flow rocks, unit 16 (Northern Mojave Desert) (Tertiary (4-22 Ma)) at surface, covers 5 % of this area

Tertiary volcanic flow rocks; minor pyroclastic deposits.

Lithology: rhyolite; basalt; tuff; ash-flow tuff; ignimbrite; dacite; trachyte; trachyandesite; trachybasalt

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

Permian marine sedimentary rocks, unit 1 (Death Valley and Mojave Desert) (Pennsylvanian to Triassic) at surface, covers < 0.1 % of this area

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

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

Triassic marine rocks, unit 1 (Death Valley area and Mojave Desert) (Early to Middle Triassic) at surface, covers < 0.1 % of this area

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

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

Schist of various types and ages, unit 2 (Southern and West-central California) (Late Cretaceous to Eocene) at surface, covers 0.2 % of this area

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

Lithology: mica schist; mica schist; amphibolite; quartzite; marble; serpentinite

Schist of various types and ages, unit 10 (Halloran Complex) (Precambrian) at surface, covers < 0.1 % of this area

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

Lithology: schist

Miocene marine rocks (Oligocene to Pliocene) at surface, covers 0.2 % of this area

Sandstone, shale, siltstone, conglomerate and breccia; in part Pliocene and Oligocene.

Lithology: sandstone; mudstone; siltstone; evaporite; conglomerate

Precambrian rocks, undivided, unit 2 (Mojave Desert and Transverse Ranges) (Early Proterozoic to Miocene) at surface, covers 3 % of this area

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

Lithology: gneiss; granitoid; amphibolite; quartzite; schist; hornfels; marble; granofels; granite; syenite; carbonatite; chert

Tertiary pyroclastic and volcanic mudflow deposits, unit 8 (Northern Mojave Desert) (Tertiary (4-22 Ma)) at surface, covers 1 % of this area

Tertiary pyroclastic and volcanic mudflow deposits.

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

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

Limestone and sparse dolomite, siltstone, and sandstone (Mississippian to Early Permian) at surface, covers < 0.1 % 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

pre-Cenozoic granitic and metamorphic rocks undivided (Early Proterozoic to Late Cretaceous) at surface, covers 0.7 % 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

Cambrian marine rocks (Late Proterozoic to Middle Devonian) at surface, covers 0.7 % 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

Quaternary volcanic flow rocks, unit 7, questionably identified (Mojave Desert) (Quaternary) at surface, covers < 0.1 % of this area

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

Lithology: basalt; tephrite (basanite); andesite

Paleozoic marine rocks, undivided, unit 2 (Northern Mojave Desert and Southeastern Sierra Nevada) (Cambrian to Jurassic) at surface, covers 0.1 % of this area

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

Lithology: argillite; chert; phyllite; sandstone; conglomerate; limestone; quartzite; marble; hornfels; slate; dolostone (dolomite)

Metamorphic rocks (Early Proterozoic) at surface, covers < 0.1 % 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

Quaternary sand deposits, unit 2 (inland) (Quaternary) at surface, covers 2 % of this area

Extensive marine and nonmarine sand deposits, generally near the coast or desert playas

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

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

GRANITIC ROCKS-Porphyritic rapakivi granite.

Lithology: granite

Paleozoic metavolcanic rocks, unit 6 (El Paso Mountains) (Devonian(?) and Permian) at surface, covers < 0.1 % of this area

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

Lithology: greenstone; andesite

Cretaceous marine rocks (in part nonmarine), unit 3 (Mescal Range) (Middle Jurassic to late Early Cretaceous) at surface, covers < 0.1 % of this area

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

Lithology: felsic volcanic rock; basalt; sandstone; mudstone

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

Precambrian rocks, undivided, unit 1 (Death Valley) (Early Proterozoic to Mesozoic) at surface, covers 0.6 % 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

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

Mesozoic gabbroic rocks, unit 2 (undivided) (Triassic to Cretaceous) at surface, covers 0.3 % of this area

Gabbro and dark dioritic rocks; chiefly Mesozoic

Lithology: gabbro; diorite

Pliocene marine rocks (Miocene to Pleistocene) at surface, covers < 0.1 % of this area

Sandstone, siltstone, shale, and conglomerate; in part Pleistocene and Miocene.

Lithology: sandstone; mudstone; siltstone; claystone; conglomerate

Plio-Pleistocene and Pliocene loosely consolidated deposits (Miocene to Pleistocene) at surface, covers 3 % 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

Limestone of probable Paleozoic or Mesozoic age (Paleozoic to Mesozoic) at surface, covers < 0.1 % of this area

Limestone, dolomite, and marble whose age is uncertain but probably Paleozoic or Mesozoic

Lithology: limestone; marble; dolostone (dolomite)

Early Tertiary to Late Cretaceous granitic rocks (Late Cretaceous to Early Tertiary) at surface, covers < 0.1 % of this area

Porphyritic to equigranular granite to diorite emplaced during the Laramide orogeny. Larger plutons are characteristically medium-grained, biotite +/- hornblende granodiorite to granite. Smaller, shallow-level intrusions are typically porphyritic. Most of the large copper deposits in Arizona are associated with porphyritic granitic rocks of this unit, and are thus named 'porphyry copper deposits'. (50-82 Ma)

Lithology: granodiorite; granite; diorite; porphyry; quartz diorite; aplite; gabbro; pegmatite; skarn

Miocene nonmarine rocks (Oligocene to Pleistocene) at surface, covers 1 % of this area

Sandstone, shale, conglomerate, and fanglomerate; in part Pliocene and Oligocene.

Lithology: sandstone; conglomerate; siltstone; mudstone; sedimentary breccia; limestone; dolostone (dolomite); chert; felsic volcanic rock (aphanitic); basalt

Andesite and basalt flows (Early Miocene to Early Pliocene) at surface, covers < 0.1 % 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

Cenozoic (Tertiary) granitic rocks, unit 1 (Death Valley) (middle to late Miocene) at surface, covers 0.3 % of this area

Cenozoic (Tertiary) granitic rocks--quartz monzonite, quartz latite, and minor monzonite, granodiorite, and granite; found in the Kingston, Panamint, Amargosa, and Greenwater Ranges in southeastern California.

Lithology: quartz monzonite; granite; monzonite; granodiorite; latite; aplite

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

Intrusive rocks (Late Cretaceous to Middle Miocene) at surface, covers < 0.1 % 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

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

Sequences of diverse volcanic rocks with abundant interbedded sedimentary rocks. (11-32 Ma)

Lithology: andesite; basalt; conglomerate; dacite; rhyolite; sandstone; sedimentary breccia; limestone; siltstone

Paleozoic marine rocks, undivided, unit 1 (Mojave Desert and Death Valley area) (Late Proterozoic to Jurassic) at surface, covers 0.3 % of this area

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

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

Schist of various types and ages, unit 5 (Slate Range) (Mesozoic) at surface, covers < 0.1 % of this area

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

Lithology: schist; gneiss; slate

Precambrian igneous and metamorphic rock complex (Early Proterozoic to Miocene) at surface, covers 3 % of this area

Complex of Precambrian igneous and metamorphic rocks. Mostly gneiss and schist intruded by igneous rocks; may be Mesozoic in part.

Lithology: gneiss; granitoid; anorthosite; syenite; diorite; amphibolite

Jurassic marine rocks, unit 3 (Mojave Desert) (Jurassic) at surface, covers < 0.1 % of this area

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

Lithology: orthoquartzite; felsic volcanic rock

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

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

Con-glomerate, sandstone, mudstone, limestone, and rock-avalanche breccia (sheet-like deposits of crushed rock) deposited and tilted during widespread normal faulting and basin development. Sediments, mostly conglomerate and sandstone, are commonly medium to dark brown, reddish brown, or brownish gray; younger strata are generally lighter colors. Most deposits are 20 to 30 Ma in southeastern Arizona and 15 to 25 Ma in central and western Arizona. (11-32 Ma)

Lithology: conglomerate; sandstone; sedimentary breccia; siltstone; limestone; mudstone; landslide

Mesozoic volcanic rocks, unit 3 (Mojave Desert, Death Valley area, and Eastern Sierra Nevada) (Triassic to Cretaceous) at surface, covers 0.9 % 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

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

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

Lithology: glacial drift

Precambrian granitic rocks, unit 1 (Eastern Mojave Desert) (Early Proterozoic to Miocene) at surface, covers 1.0 % of this area

Precambrian granite, syenite, anorthosite, and gabbroic rocks in the San Gabriel Mountains; also various Precambrian plutonic rocks elsewhere in southeastern California

Lithology: granite; granodiorite; gneiss; diorite; gabbro; anorthosite; syenite

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)

Tertiary nonmarine rocks, undivided (Paleocene to Pliocene) at surface, covers 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

Tertiary intrusive rocks (hypabyssal), unit 7 (Northern Mojave Desert) (Tertiary) at surface, covers 0.7 % of this area

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

Lithology: rhyolite; basalt; dacite; trachyte

Quaternary volcanic flow rocks, unit 7 (Mojave Desert) (Quaternary) at surface, covers 0.7 % of this area

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

Lithology: basalt; tephrite (basanite); andesite

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

Mesozoic granitic rocks , unit 2 (Peninsular Ranges) (Middle Jurassic to Late Cretaceous) at surface, covers < 0.1 % of this area

Mesozoic granite, quartz monzonite, granodiorite, and quartz diorite

Lithology: tonalite; quartz diorite; granodiorite; quartz monzonite; granite; gneiss; schist; pegmatite