A Caltech Library Service

The tectonic crustal stress field and style of faulting along the Pacific North America Plate boundary in Southern California

Yang, Wenzheng and Hauksson, Egill (2013) The tectonic crustal stress field and style of faulting along the Pacific North America Plate boundary in Southern California. Geophysical Journal International, 194 (1). pp. 100-117. ISSN 0956-540X. doi:10.1093/gji/ggt113.

PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


We invert for the state of stress in the southern California crust using a catalogue of high quality earthquake focal mechanisms (1981–2010). The stress field is best resolved where seismicity rates are high and sufficient data are available to constrain the stress field across most of the region. From the stress field, we determine the maximum horizontal compressive stress (S_Hmax) orientations and the style of faulting across southern California. The trend of S_Hmax exhibits significant regional and local spatial heterogeneities. The regional trend of S_Hmax varies from north along the San Andreas system to NNE to the east in the Eastern California Shear Zone as well as to the west, within the Continental Borderland and the Western Transverse Ranges. The transition zones from one state of stress to the other occur over a distance of only a few kilometres, following a trend from Yucca Valley to Imperial Valley to the east, and the western edge of the Peninsular Ranges to the west. The local scale heterogeneities in the S_Hmax trend include NNW trends along the San Andreas Fault near Cajon Pass, Tejon Pass and the Cucapah Range, as well as NNE trends near the northern San Jacinto Fault and the Wheeler Ridge area. The style of faulting exhibits similar complexity, ranging from predominantly normal faulting in the high Sierra Nevada, to strike-slip faulting along the San Andreas system, to three consecutive bands of thrust faulting in the Wheeler Ridge area and the Western Transverse Ranges. The local variations in the style of faulting include normal faulting at the north end of the San Jacinto Fault and scattered areas of thrust faulting. The regional variations in the SHmax trends are very similar to the pattern of the GPS-measured maximum shortening axes of the surface strain rate tensor field although the strain field tends to be smoother and appears to capture some of the upper-mantle deformation field. The mean trend of S_Hmax departs about approximately 14° to the east from the trend of the maximum shortening directions derived from anisotropy in the upper mantle.

Item Type:Article
Related URLs:
URLURL TypeDescription
Hauksson, Egill0000-0002-6834-5051
Additional Information:© The Authors 2013. Published by Oxford University Press on behalf of The Royal Astronomical Society. Accepted 2013 March 19; Received 2013 March 12; In original form 2012 October 22. We thank the personnel of the USGS/Caltech Southern California Seismic Network (SCSN) who pick arrival times and archive the seismograms and the Southern California Earthquake Data Center (SCEDC) for distributing the data. Funding for this research was provided by NEHRP/USGS grant 12HQPA0001. This research was also supported by the Southern California Earthquake Center, which is funded by NSF Cooperative Agreement EAR-0106924 and USGS Cooperative Agreement 02HQAG0008. This is SCEC contribution 1677 and contribution number 10082, Seismological Laboratory, Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena.We appreciate Jeanne Hardebeck and Andy Michael for making the SATSI program available. We appreciate Carl Tape for useful discussions on strain rate tensor, and William Holt for providing strain rate tensor results for southern California. We appreciate Joann Stock for valuable comments and suggestions. We appreciate editor Saskia Goes and two anonymous reviewers for constructive comments and valuable suggestions.
Group:Seismological Laboratory
Funding AgencyGrant Number
Southern California Earthquake Center (SCEC)UNSPECIFIED
Subject Keywords:Seismicity and tectonics; Continental margins: transform; Dynamics: seismotectonics; High strain deformation zones; Crustal structure; North America
Issue or Number:1
Record Number:CaltechAUTHORS:20130725-094607382
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:39579
Deposited On:29 Jul 2013 21:50
Last Modified:09 Nov 2021 23:45

Repository Staff Only: item control page