A new angle on the tectonic evolution of the Ridge basin, a "strike-slip" basin in southern California

Abstract

Research Article| October 01, 1993 A new angle on the tectonic evolution of the Ridge basin, a "strike-slip" basin in southern California STEVEN R. MAY; STEVEN R. MAY 1Exxon Production Research Co., Houston, Texas 77252-2189 Search for other works by this author on: GSW Google Scholar KENNETH D. EHMAN; KENNETH D. EHMAN 1Exxon Production Research Co., Houston, Texas 77252-2189 Search for other works by this author on: GSW Google Scholar GARY G. GRAY; GARY G. GRAY 1Exxon Production Research Co., Houston, Texas 77252-2189 Search for other works by this author on: GSW Google Scholar JOHN C. CROWELL JOHN C. CROWELL 2Institute for Crustal Studies, University of California, Santa Barbara, California 93106-1100 Search for other works by this author on: GSW Google Scholar Author and Article Information STEVEN R. MAY 1Exxon Production Research Co., Houston, Texas 77252-2189 KENNETH D. EHMAN 1Exxon Production Research Co., Houston, Texas 77252-2189 GARY G. GRAY 1Exxon Production Research Co., Houston, Texas 77252-2189 JOHN C. CROWELL 2Institute for Crustal Studies, University of California, Santa Barbara, California 93106-1100 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1993) 105 (10): 1357–1372. https://doi.org/10.1130/0016-7606(1993)105<1357:ANAOTT>2.3.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation STEVEN R. MAY, KENNETH D. EHMAN, GARY G. GRAY, JOHN C. CROWELL; A new angle on the tectonic evolution of the Ridge basin, a "strike-slip" basin in southern California. GSA Bulletin 1993;; 105 (10): 1357–1372. doi: https://doi.org/10.1130/0016-7606(1993)105<1357:ANAOTT>2.3.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract The Ridge basin, located in southern California between the San Andreas and San Gabriel faults, contains as much as 14 km of Mio-Pliocene marine and nonmarine sedimentary fill. These strata are exposed as a northwest-dipping homoclinal sequence that becomes increasingly younger to the northwest. Pliocene to Holocene deformation, uplift, and dissection of this basin provide an opportunity to study stratal geometry and sedimentary facies in what is commonly cited as a classic "strike-slip" basin. Newly acquired seismic data from the northern Ridge basin provide new evidence for the subsurface basin geometry. These data lead us to conclude that the principal northern strand of the San Gabriel fault is a listric, east-southeast-dipping, oblique-slip fault rather than a subvertical, strike-slip fault.The principal San Gabriel fault appears to become subhorizontal at the southeastern end of the seismic line at a present-day sub-surface depth of ∼4 km. This interpretation is consistent with preliminary two-dimensional gravity models across the basin and with the homoclinal structure of basin fill. Subsidence within the Ridge basin is explained as the result of northwest- southeast extension locally accommodated along the listric, right-lateral San Gabriel and associated late Miocene strike-slip faults. As a consequence of oblique normal slip on the gently dipping San Gabriel fault, sedimentary strata were continuously tilted and moved southeastward in the hanging wall away from the depocenter. This mechanism of basin formation allowed 14 km of sediment to accumulate without deep burial. The geometry and displacement history of the San Gabriel fault controlled sediment accommodation and resultant stratal geometries within the basin. Slip along the San Gabriel fault and associated subsidence of the Ridge basin correspond temporally with regional tectonic events in southern California, reflecting both changes in the relative motion of Pacific and North American plates and the evolution of strain partitioning across this plate boundary. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.