Open AccessSource parameters for the 1952 Kern County earthquake, California: A joint inversion of leveling and triangulation observations
Author(s) -
Bawden Gerald W.
Publication year - 2001
Publication title -
journal of geophysical research: solid earth
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2000jb900315
Subject(s) - geology , seismology , slip (aerodynamics) , thrust fault , geodetic datum , geodesy , seismic moment , inversion (geology) , fault (geology) , tectonics , physics , thermodynamics
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.