Source parameters for the 1952 Kern County earthquake, California: A joint inversion of leveling and triangulation observations

G.W. Bawden

doi:10.1029/2000jb900315

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Source parameters for the 1952 Kern County earthquake, California: A joint inversion of leveling and triangulation observations

G.W. Bawden

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Abstract

Coseismic leveling and triangulation observations are used to determine the faulting geometry and slip distribution of the July 21, 1952, M w 7.3 Kern County earthquake on the White Wolf fault. A singular value decomposition inversion is used to assess the ability of the geodetic network to resolve slip along a multisegment fault and shows that the network is sufficient to resolve slip along the surface rupture to a depth of 10 km. Below 10 km, the network can only resolve dip slip near the fault ends. The preferred source model is a two-segment right-stepping fault with a strike of 51° and a dip of 75° SW. The epicentral patch has deep (6–27 km) left-lateral oblique slip, while the northeastern patch has shallow (1–12.5 km) reverse slip. There is nearly uniform reverse slip (epicentral, 1.6 m; northeast, 1.9 m), with 3.6 m of left-lateral strike slip limited to the epicentral patch. The seismic moment is M 0 = 9.2 ± 0.5 × 10 19 N m ( M w = 7.2). The signal-to-noise ratio of the leveling and triangulation data is reduced by 96% and 49%, respectively. The slip distribution from the preferred model matches regional geomorphic features and may provide a driving mechanism for regional shortening across the Comanche thrust and structural continuity with the Scodie seismic lineament to the northeast.

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Journal of Geophysical Research B: Solid Earth Article

Source-reported bounding extent: 34.7902° to 35.7988° latitude; -120.1951° to -117.6166° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

G.W. Bawden. 2001-01-10. Source parameters for the 1952 Kern County earthquake, California: A joint inversion of leveling and triangulation observations. https://doi.org/10.1029/2000jb900315

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