Compression directions north of the San Fernando Valley determined from borehole breakouts
- Creators
- Kerkela, Stacy
-
Stock, Joann M.
Abstract
Borehole breakouts in 4 nearly vertical oil wells, and several other deviated holes, in the San Fernando Valley and Santa Susana Mountains suggest a maximum horizontal compressive stress direction (S_H) of N49°W. These wells provide information about the stress field from 1974 to 1983 in the uppermost crust (<3 km depth) near the aftershock zones of the January 1994 Northridge earthquake and the February 1971 Sylmar earthquake. This direction of S_H is anomalous with respect to the N to NNE directions of S_H seen in other regional data, but is consistent with the structural complexity of this zone, including local changes in strike of major thrust fault zones and the presence of lateral ramps in both the Santa Susana and San Fernando faults.
Additional Information
© 1996 American Geophysical Union. Manuscript Accepted: 29 Aug 1996. Manuscript Received: 11 Jul 1995. Paper number 96GL03054. We thank the Southern California Gas Company for providing access to some of the data. This study was funded by Caltech SURF (Summer Undergraduate Research Fellowship) program and by the Southern California Earthquake Center (NSF Grant EAR-89-20136). We thank Colleen Barton, Mike Bruno, and Bob Yeats for very helpful reviews of this paper. SCEC Publication number 342. Contribution Number 5577, Caltech Seismological Laboratory.Attached Files
Published - grl9725.pdf
Supplemental Material - KerkelaStock96GL03054-1997-Supplementary.pdf
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Additional details
- Eprint ID
- 44932
- Resolver ID
- CaltechAUTHORS:20140414-132129630
- Caltech Summer Undergraduate Research Fellowship (SURF)
- Southern California Earthquake Center
- EAR 89-20136
- NSF
- Created
-
2014-04-14Created from EPrint's datestamp field
- Updated
-
2021-11-10Created from EPrint's last_modified field
- Caltech groups
- Seismological Laboratory, Division of Geological and Planetary Sciences
- Other Numbering System Name
- Caltech Seismological Laboratory
- Other Numbering System Identifier
- 5577