Source parameters of the 1980 Mammoth Lakes, California, earthquake sequence

Ralph J. Archuleta; Edward Cranswick; Charles Mueller; Paul Spudich

doi:10.1029/jb087ib06p04595

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Source parameters of the 1980 Mammoth Lakes, California, earthquake sequence

Ralph J. Archuleta·Edward Cranswick·Charles Mueller·Paul Spudich

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Abstract

From the more than 1500 Mammoth Lakes earthquakes recorded on three-component digital seismographs (Spudich et al., 1981), 150 were used in an analysis of the locations, mechanism, and source parameters. A composite fault plane solution of nine earthquakes 3.9 ≤ M ≤ 5.1 defines a right-lateral strike slip mechanism on a steeply dipping nearly east-west plane striking S75°E or left-lateral strike slip on a nearly north-south plane striking N10°E. Vertical cross sections of well-located aftershocks indicate possibly three east-west planes that coincide with the locations of the four largest earthquakes with M L ≥ 6.0. Using the spectral analysis of S waves (Brune, 1970), source parameters for 67 earthquakes were determined. Forty-eight had magnitudes greater than or equal to 3.0. Seismic moments ranged from 9.20×10 18 dyn cm to 2.33×10 24 dyn cm. Earthquakes with seismic moment greater than about 1.0×10 21 dyn cm had nearly constant stress drops (≃ 50 bars); earthquakes with seismic moment less than about 1.0×10 21 dyn cm had stress drops that apparently decrease as seismic moment decreases.

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Journal of Geophysical Research B: Solid Earth Article

Source-reported bounding extent: 37.4622° to 38.7084° latitude; -119.6494° to -117.8357° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Ralph J. Archuleta, Edward Cranswick, Charles Mueller, Paul Spudich. 2012-09-20. Source parameters of the 1980 Mammoth Lakes, California, earthquake sequence. https://doi.org/10.1029/jb087ib06p04595

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