State of stress near the San Andreas fault: Implications for wrench tectonics

Research Article| December 01, 1987 State of stress near the San Andreas fault: Implications for wrench tectonics Van S. Mount; Van S. Mount 1Department of Geological and Geophysical Sciences, Princeton University, Princeton, New Jersey 08544 Search for other works by this author on: GSW Google Scholar John Suppe John Suppe 1Department of Geological and Geophysical Sciences, Princeton University, Princeton, New Jersey 08544 Search for other works by this author on: GSW Google Scholar Author and Article Information Van S. Mount 1Department of Geological and Geophysical Sciences, Princeton University, Princeton, New Jersey 08544 John Suppe 1Department of Geological and Geophysical Sciences, Princeton University, Princeton, New Jersey 08544 Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1987) 15 (12): 1143–1146. https://doi.org/10.1130/0091-7613(1987)152.0.CO;2 Article history First Online: 02 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 Van S. Mount, John Suppe; State of stress near the San Andreas fault: Implications for wrench tectonics. Geology 1987;; 15 (12): 1143–1146. doi: https://doi.org/10.1130/0091-7613(1987)152.0.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 SocietyGeology Search Advanced Search Abstract Borehole elongations or breakouts in central California show that the direction of regional maximum horizontal stress is nearly perpendicular to the San Andreas fault and to the axes of young thrust-related anticlines. This observation resolves much of the controversy over shear-stress magnitude in the crust and around the San Andreas fault specifically. A low shear stress of 10–20 MPa (100–200 bar) or less on the San Andreas fault, suggested by heat-flow and seismic observations, is compatible with a high regional deviatoric stress (100 MPa, 1 kbar) when the observed principal stress directions are considered. Therefore, the San Andreas fault is a nearly frictionless interface, which causes the transpressive plate motion to be decoupled into a low-stress strike-slip component and a high-stress compressive component. These observations suggest that standard concepts of transpressive wrench tectonics—which envisage drag on a high-friction fault—are wrong. The thrust structures are largely decoupled from the strike-slip fault. 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.