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The Borrego Mountain, California, earthquake of 9 April 1968: A preliminary report

Allen, C. R. and Grantz, A. and Brune, J. N. and Clark, M. M. and Sharp, R. V. and Theodore, T. G. and Wolfe, E. W. and Wyss, M. (1968) The Borrego Mountain, California, earthquake of 9 April 1968: A preliminary report. Bulletin of the Seismological Society of America, 58 (3). pp. 1183-1186. ISSN 0037-1106.

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The largest earthquake to hit California in more than 15 years occurred at 02:28:58.9 GCT on 9 April 1968 near Borrego Mountain, on the western edge of the Imperial Valley. The Seismological Laboratory at Pasadena has tentatively assigned the shock a magnitude of 6.5, an epicentral location of 33 ° 08.8' N, 116 ° 07.5' W, and a focal depth of 20 km. The earthquake was felt throughout most of southern California and adjacent areas, but the absence of severe damage and casualties was in large part due to the relatively undeveloped nature of the epicentral region. Indeed, it would have been difficult to pick a location in the southernmost part of the State more remote from centers of population.

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Additional Information:Copyright © 1968, by the Seismological Society of America. Manuscript received April 29, 1968. Participation in this study by the California Institute of Technology was supported by National Science Foundation Grant GA-1087. A joint contribution of the California Institute of Technology, Division of Geological Sciences (Contribution No. 1532) and the National Center for Earthquake Research, U.S. Geological Survey.
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Division of Geological Sciences1532
Issue or Number:3
Record Number:CaltechAUTHORS:20140808-162822683
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:48270
Deposited By: George Porter
Deposited On:11 Aug 2014 14:38
Last Modified:03 Oct 2019 07:02

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