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Research about Los Angeles, California

Source-linked reports with geographic coverage including Los Angeles, California.

62 records · Page 4Linked to original sources

Nuclear event time histories and computed site transfer functions for locations in the Los Angeles region

This report presents a collection of Nevada Test Site (NTS) nuclear explosion recordings obtained at sites in the greater Los Angeles, Calif., region. The report includes ground velocity time histories, as well as, derived site transfer functions. These data have been collected as part of a study to evaluate the validity of using low-level ground motions to predict the frequency-dependent response of a site during an earthquake. For this study 19 nuclear events were recorded at 98 separate locations. Some of these sites have recorded more than one of the nuclear explosions, and, consequently, there are a total of 159, three-component station records. The location of all the recording sites are shown in figures 1–5, the station coordinates and abbreviations are given in table 1. The station addresses are listed in table 2, and the nuclear explosions that were recorded are listed in table 3. The recording sites were chosen on the basis of three criteria: (1) that the underlying geological conditions were representative of conditions over significant areas of the region, (2) that the site was the location of a strong-motion recording of the 1971 San Fernando earthquake, or (3) that more complete geographical coverage was required in that location.

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In-situ measurements of seismic velocity at 27 locations in the Los Angeles, California region

Studies conducted in the San Francisco Bay Region (Gibbs, Fumal and Borcherdt, 1980) have shown that average shear-wave velocity can be readily tied to quantitative estimates of ground motion such as ground amplification and earthquake intensity. Furthermore, when certain physical properties of the geologic materials such as texture, hardness and fracture spacing are observed during geologic mapping, a method can be used to predict shear-wave velocity from the descriptions of geologic units. By measuring shear-wave velocities in key units together with the above data, regional maps depicting the earthquake shaking hazard can be compiled. The goals of the current program are to provide shear-wave data in the Los Angeles area to compare with that in the San Francisco Bay Region where high-strain intensity data are available. Data from twenty-seven locations are summarized in this report as part of a continuing project to seismically zone the Los Angeles area.

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Proceedings of Conference XII; Earthquake prediction information

The U.S. Geological Survey in cooperation with five cosponsors: California Division of Mines and Geology, California Emergency Services, California Seismic Safety Commission, City of Los Angeles, and Federal Emergency Management Agency, convened a conference on Earthquake Prediction Information in Los Angeles during the period January 28-30, 1980. More than 100 government officials, scientists, engineers, social scientists, and civic and community leaders participated in the three day conference. The purpose of the conference was to provide a forum for presenting basic information on the state-of-the art of earthquake prediction and to identify constructive responses that might be taken through broad cooperative community participation both before and after an actual prediction of an earthquake.

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