Quaternary faults at San Diego Bay, California

Journal of Research of the U.S. Geological Survey
By:  and 



Acoustic-reflection profiles of subbottom strata reveal numerous faults that cut Quaternary deposits within and directly outside of San Diego Bay. These faults, together with previously mapped onshore faults, constitute the Rose Canyon fault zone that forms the local west boundary of the Santa Ana tectonic block, which is bounded on the east by the Elsinore fault zone. The minor earthquakes that have been felt in San Diego during historic time and accurately recorded during the past 41 yr are too infrequent to explain the observed rate of slip. The principal faulting is inferred to take place during moderate earthquakes similar to previous ones recorded along the west side of the Santa Ana block in 1933 at Long Beach, Calif., and in 1956 at San Miguel, Baja California. The known magnitudes of these previous events suggest that earthquakes in San Diego could attain a magnitude of approximately 6.5. An offset of the coast at Point La Jolla, when divided by the offset associated with previously studied earthquakes of magnitude 6.5, suggests that such events occur there at an average of approximately once every 600 yr.

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Publication type Article
Publication Subtype Journal Article
Title Quaternary faults at San Diego Bay, California
Series title Journal of Research of the U.S. Geological Survey
Volume 3
Issue 5
Year Published 1975
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Description 7 p.
First page 589
Last page 595
Country United States
State California
Other Geospatial San Diego Bay
Online Only (Y/N) N
Additional Online Files (Y/N) N
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