Transtensional model for the Sierra Nevada frontal fault system, eastern California

Abstract

Research Article| April 01, 2003 Transtensional model for the Sierra Nevada frontal fault system, eastern California Jeffrey Unruh; Jeffrey Unruh 1William Lettis & Associates, Inc., 1777 Botelho Drive, Suite 262, Walnut Creek, California 94596, USA Search for other works by this author on: GSW Google Scholar James Humphrey; James Humphrey 2Lahontan GeoScience, Inc., 1105 Terminal Way, Suite 202, Reno, Nevada 89502, USA Search for other works by this author on: GSW Google Scholar Andrew Barron Andrew Barron 3William Lettis & Associates, Inc., 1777 Botelho Drive, Suite 262, Walnut Creek, California 94596, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Jeffrey Unruh 1William Lettis & Associates, Inc., 1777 Botelho Drive, Suite 262, Walnut Creek, California 94596, USA James Humphrey 2Lahontan GeoScience, Inc., 1105 Terminal Way, Suite 202, Reno, Nevada 89502, USA Andrew Barron 3William Lettis & Associates, Inc., 1777 Botelho Drive, Suite 262, Walnut Creek, California 94596, USA Publisher: Geological Society of America Received: 19 Jul 2002 Revision Received: 18 Nov 2002 Accepted: 24 Nov 2002 First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (2003) 31 (4): 327–330. https://doi.org/10.1130/0091-7613(2003)031<0327:TMFTSN>2.0.CO;2 Article history Received: 19 Jul 2002 Revision Received: 18 Nov 2002 Accepted: 24 Nov 2002 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 Jeffrey Unruh, James Humphrey, Andrew Barron; Transtensional model for the Sierra Nevada frontal fault system, eastern California. Geology 2003;; 31 (4): 327–330. doi: https://doi.org/10.1130/0091-7613(2003)031<0327:TMFTSN>2.0.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 Active strike-slip and normal faults along the eastern margin of the Sierra Nevada primarily accommodate northwestward translation of the Sierra Nevada–Central Valley (i.e., Sierran) microplate with respect to stable North America. Strike-slip faults bordering the eastern Sierran microplate are subparallel to small circles about the Sierra Nevada–North American Euler pole. Normal faults of the Sierra Nevada frontal fault system strike ∼45° clockwise of the small circle trajectories and exhibit well-defined, left-stepping en echelon patterns, consistent with formation in dextral transcurrent regime. Major graben bordering the northeastern Sierran microplate are located in regions where the locus of range-front deformation steps abruptly eastward in a releasing geometry relative to Sierra Nevada–North American motion. Crustal shortening occurs at the northern end of the Sierran microplate, where a component of northwest dextral shear steps westward in a left-restraining geometry across the Sierran crest to the Sacramento Valley. Kinematic inversions of earthquake focal mechanisms from the Walker Lane belt bordering the eastern Sierra Nevada indicate that seismogenic deformation primarily is characterized by horizontal shearing and oblique crustal thinning. Directions of macroscopic dextral shear inferred from the inversions are subparallel to the trajectories of small circles about the Sierra Nevada–North American Euler pole. Normal faulting along most of the eastern Sierran range front thus appears to primarily accommodate microplate translation rather than Sierran uplift or regional Basin and Range extension. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.