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Seismicity of California's north coast

William H. Bakun
Seismicity of California's north coast
Bulletin of the Seismological Society of America (August 2000) 90 (4): 797-812


At least three moment magnitude (M) 7 earthquakes occurred along California's north coast in the second half of the nineteenth century. The M 7.3 earthquake on 23 November 1873 occurred near the California-Oregon coast and likely was located on the Cascadia subduction zone or within the North American plate. The M 7.0+ earthquake on 9 May 1878 was located about 75 km offshore near the Mendocino fault. The surface-wave magnitude (M (sub s) ) 7.0 earthquake on 16 April 1899 was located about 150 km offshore within the Gorda plate. There were at least three M 7 north-coast earthquakes in the 35 years before 1906, two M 7 earthquakes in the 20 years after 1906, no M 7 earthquakes from 1923 until 1980, and four M 7 earthquakes since 1980. The relative seismic quiescence after 1906 for M 7 earthquakes along California's north coast mimics the post-1906 seismic quiescence in the San Francisco Bay area for M 6 earthquakes. The post-1906 relative quiescence did not extend to lower magnitudes in either area. The 18 April 1906 earthquake apparently influenced the rate of occurrence of M 7 north-coast earthquakes as it apparently influenced the rate of M 6 earthquakes in the San Francisco Bay area. The relative seismic quiescence along the California north-coast region after 1906 should be taken into account when evaluating seismic hazards in northwest California.

ISSN: 0037-1106
EISSN: 1943-3573
Serial Title: Bulletin of the Seismological Society of America
Serial Volume: 90
Serial Issue: 4
Title: Seismicity of California's north coast
Author(s): Bakun, William H.
Affiliation: U. S. Geological Survey, Earthquake Hazards Team, Menlo Park, CA, United States
Pages: 797-812
Published: 200008
Text Language: English
Publisher: Seismological Society of America, Berkeley, CA, United States
References: 64
Accession Number: 2003-006250
Categories: Seismology
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus. incl. 2 tables, geol. sketch maps
N40°00'00" - N41°00'00", W126°00'00" - W123°00'00"
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2018, American Geosciences Institute.
Update Code: 200302
Program Name: USGSOPNon-USGS publications with USGS authors
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