The stratigraphic evolution of the El Paso basin, southern California: Implications for the Miocene development of the Garlock fault and uplift of the Sierra Nevada

Abstract

The stratigraphic evolution of the El Paso basin, southern California: Implications Email alerting services this article to receive free e-mail alerts when new articles cite www.gsapubs.org/cgi/alerts click Subscribe America Bulletin to subscribe to Geological Society of www.gsapubs.org/subscriptions/ click Permission request to contact GSA http://www.geosociety.org/pubs/copyrt.htm#gsa click presented in this publication do not reflect official positions of the Society. scientists worldwide, regardless of their race, citizenship, gender, religion, or political viewpoint. Opinions citation. GSA provides this and other forums for the presentation of diverse opinions and positions by on their own or their organization's Web site providing the posting includes a reference to the article's full science. This file may not be posted to any Web site, but authors may post the abstracts only of their articles unlimited copies of items in GSA's journals for noncommercial use in classrooms to further education and use a single figure, a single table, and/or a brief paragraph of text in subsequent works and to make employment. Individual scientists are hereby granted permission, without fees or further requests to GSA, to

Preliminary Surficial Geology of the Dove Spring Off-Highway Vehicle Open Area, Mojave Desert, California

“…Early deposition in the Ricardo Group (Cudahy Camp Formation) consisted of largely volcaniclastic sediments, derived from the east and south, delivered in two distinct episodes during the Miocene (Loomis and Burbank, 1988). Much of the unit was deposited in an extensional basin interpreted to have formed north of the Garlock Fault.…”

“…Base of section about 7 Ma (Loomis and Burbank, 1988). Deposits of the Ricardo Group generally are tilted northwest, but dips decrease upsection and are subhorizontal in the upper part.…”

“…Evidently, the Holocene activity along the Sierra Nevada frontal fault system farther north in Owens Valley is not represented along this segment of the fault system. It has been suggested by Loomis and Burbank (1988) that the upper part of the Ricardo Group represents basinal sedimentation driven by uplift of the Sierra Nevada. If so, the youngest NW-dipping strata of the Ricardo, questionably Pleistocene in age (Dibblee, 1952), indicate activity of the Sierra Nevada frontal fault until that time.…”

“…The upper part of the Ricardo Group named the Dove Spring Formation (Loomis and Burbank, 1988), is Miocene to Pliocene (Burbank and Whistler, 1987) and clastic sources change near the top from volcanic to granitic rocks. The granite source is inferred to be the Sierra Nevada based on lithology, clast-size trends, and facies relationships (Loomis and Burbank, 1988). The upper part of the Dove Spring Formation is overlain concordantly by weakly bedded, grussy gravel that is of uncertain age.…”

“…Considered to be Pleistocene by Dibblee (1952) and Pliocene by Whistler (1987) Tr Lower part (Miocene)-Poorly to moderately consolidated bedded gravel, sand, silt and clay containing interbedded andesite, basalt, and rhyolite. The Ricardo Formation was considered to be Miocene by Dibblee(1952), Diggles (1986), andWhistler (1987), and was raised to group status by Loomis and Burbank (1988). The Ricardo Group is divided into the Dove Spring Formation that overlies the Cudahy Camp Formation (Loomis and Burbank, 1988).…”