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The seismic cycle in southern California: Precursor or response?

Jones, Lucile M. and Hauksson, Egill (1997) The seismic cycle in southern California: Precursor or response? Geophysical Research Letters, 24 (4). pp. 469-472. ISSN 0094-8276. doi:10.1029/97GL00188.

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The seismicity rate (M ≥ 3.0) in southern California shows two cycles with periods of high activity (90 events/year), from 1945–1952 and 1969–1992, and lower activity (60–70 events /year) from 1952–1969 and 1992-present. Abrupt drops in the seismicity rate occur after the 1952 Kern County (M7.5) and the 1992 Landers (M7.3) earthquakes. The sudden increase in 1969 does not coincide with any major event but approximates the time needed to reaccumulate the seismic moment released in the 1952 earthquake. This temporal correlation with the preceding earthquake suggests that the seismic cycle (lower seismicity after a major earthquake and higher seismicity before the next major earthquake) should be interpreted as a response to the first earthquake rather than a precursor to the second. Southern California is now at a rate of seismicity as low as it experienced in the 1950s and 1960s.

Item Type:Article
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URLURL TypeDescription
Jones, Lucile M.0000-0002-2690-3051
Hauksson, Egill0000-0002-6834-5051
Additional Information:© 1997 American Geophysical Union. Received December 3, 1996; accepted January 8, 1997. We are grateful for the reviews and insightful comments from Sue Hough, Hiroo Kanamori and Bill Ellsworth. One of us (EH) was partially supported by USGS Grant 1434-94-G-2440. Contribution number 5792, Division of Geological and Planetary Sciences, California Institute of Technology.
Group:Seismological Laboratory
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Caltech Division of Geological and Planetary Sciences5792
Issue or Number:4
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:37025
Deposited On:21 Feb 2013 16:20
Last Modified:09 Nov 2021 23:26

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