Alluvium, lake, playa, and terrace deposits; unconsolidated and semi-consolidated. Mostly nonmarine, but includes marine deposits near the coast.
Older alluvium, lake, playa, and terrace deposits.
Mesozoic granite, quartz monzonite, granodiorite, and quartz diorite
Mesozoic granite, quartz monzonite, granodiorite, and quartz diorite
Complex of Precambrian igneous and metamorphic rocks. Mostly gneiss and schist intruded by igneous rocks; may be Mesozoic in part.
Conglomerate, shale, sandstone, limestone, dolomite, marble, gneiss, hornfels, and quartzite; may be Paleozoic in part
Pliocene and/or Pleistocene sandstone, shale, and gravel deposits; in part Miocene.
Extensive marine and nonmarine sand deposits, generally near the coast or desert playas
Granitic and metamorphic rocks, mostly gneiss and other metamorphic rocks injected by granitic rocks. Mesozoic to Precambrian.
Undivided pre-Cenozoic metasedimentary and metavolcanic rocks of great variety. Mostly slate, quartzite, hornfels, chert, phyllite, mylonite, schist, gneiss, and minor marble.
Shale, sandstone, minor conglomerate, chert, slate, limestone; minor pyroclastic rocks
Undated granitic rocks, unit 3 (Southern California)
Precambrian granite, syenite, anorthosite, and gabbroic rocks in the San Gabriel Mountains; also various Precambrian plutonic rocks elsewhere in southeastern California
Undivided Cretaceous sandstone, shale, and conglomerate; minor nonmarine rocks in Peninsular Ranges (?)
Gabbro and dark dioritic rocks; chiefly Mesozoic
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.
Undivided Paleozoic metasedimentary rocks. Includes slate, sandstone, shale, chert, conglomerate, limestone, dolomite, marble, phyllite, schist, hornfels, and quartzite
Schists of various types; mostly Paleozoic or Mesozoic age; some Precambrian.
Tertiary volcanic flow rocks; minor pyroclastic deposits.
Sandstone, shale, and conglomerate; in part Miocene and Eocene.
Undated granitic rocks, unit 1 (Chocolate Mountains)
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.
Sandstone, shale, and conglomerate; mostly well consolidated
Tertiary intrusive rocks; mostly shallow (hypabyssal) plugs and dikes. Includes some Mesozoic rocks.
Sandstone, shale, conglomerate, and fanglomerate; in part Pliocene and Oligocene.
Quaternary volcanic flow rocks; minor pyroclastic deposits; in part Pliocene and Miocene.
Shale, sandstone, conglomerate, and minor limestone; in part Oligocene and Paleocene.
Tertiary pyroclastic and volcanic mudflow deposits.
Undivided Tertiary sandstone, shale, conglomerate, breccia, and ancient lake deposits.
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)
Quaternary volcanic flow rocks; minor pyroclastic deposits; in part Pliocene and Miocene.
Limestone, dolomite, and marble whose age is uncertain but probably Paleozoic or Mesozoic
Selected large landslides, such as Blackhawk slide on north side of San Gabriel Mountains; early to late Quaternary.
Undivided Cretaceous sandstone, shale, and conglomerate; minor nonmarine rocks in Peninsular Ranges
Upper Cretaceous sandstone, shale, and conglomerate
Sandstone, shale, siltstone, conglomerate and breccia; in part Pliocene and Oligocene.
Undivided pre-Cenozoic metavolcanic rocks. Includes latite, dacite, tuff, and greenstone; commonly schistose.
Sandstone, siltstone, shale, and conglomerate; in part Pleistocene and Miocene.
Tertiary volcanic flow rocks; minor pyroclastic deposits.
Tertiary volcanic flow rocks; minor pyroclastic deposits.
Tertiary intrusive rocks; mostly shallow (hypabyssal) plugs and dikes. Includes some Mesozoic rocks.