Catalog of earthquakes in the Santa Monica Mountains area for the period February 21, 1973 to December 31, 1973

Sharon L. Kirkman; William L. Ellsworth

doi:10.3133/ofr77301

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Catalog of earthquakes in the Santa Monica Mountains area for the period February 21, 1973 to December 31, 1973

Sharon L. Kirkman·William L. Ellsworth

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Abstract

The Seismological Laboratory of the California Institute of Technology(CALTECH) has reported instrumentally recorded earthquakes throughout southern California since 1932. Allen and others (1965) analyzed results from the Caltech seismograph network, and related earthquake data for the period from 1934 to 1963 to the regional geologic structures in southern California. A magnitude 6.0 earthquake occurred near Point Mugu, California, approximately 15 km southeast of Oxnard, on February 21, 1973. Within 20 hours of the main shock the U.S. Geological Survey (USGS) and the California Institute of Technology, Pasadena(CALTECH) began operation of temporary portable seismograph stations to study the aftershock sequence of the earthquake (Ellsworth and others, 1973). The temporary network of stations was replaced by an enlarged, permanent seismograph network beginning in June 1973. This catalog contains the fundamental parameters for earthquakes located within and adjacent to the seismograph network operated in the western Santa Monica Mountain region by the National Center for Earthquake Research (NCER), U. S. Geological Survey, during the period from February 21, 1973 to December 31, 1973 covering the main shock and aftershocks of the Pt. Mugu earthquake. The basic data contained in this catalog provides a foundation for further study of active tectonic processes in the western Santa Monica Mountains and adjacent areas.

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Source-reported bounding extent: 32.534156° to 42.009247° latitude; -124.409591° to -114.134768° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Sharon L. Kirkman, William L. Ellsworth. 1977. Catalog of earthquakes in the Santa Monica Mountains area for the period February 21, 1973 to December 31, 1973. https://doi.org/10.3133/ofr77301

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