Steady state deformation of the Coso Range, east central California, inferred from satellite radar interferometry

C.W. Wicks; W. Thatcher; Francis C. Monastero; M.A. Hasting

doi:10.1029/2001jb000298

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Steady state deformation of the Coso Range, east central California, inferred from satellite radar interferometry

C.W. Wicks·W. Thatcher·Francis C. Monastero·M.A. Hasting

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Abstract

Observations of deformation from 1992 to 1997 in the southern Coso Range using satellite radar interferometry show deformation rates of up to 35 mm yr −1 in an area ∼10 km by 15 km. The deformation is most likely the result of subsidence in an area around the Coso geothermal field. The deformation signal has a short-wavelength component, related to production in the field, and a long-wavelength component, deforming at a constant rate, that may represent a source of deformation deeper than the geothermal reservoir. We have modeled the long-wavelength component of deformation and inferred a deformation source at ∼4 km depth. The source depth is near the brittle-ductile transition depth (inferred from seismicity) and ∼1.5 km above the top of the rhyolite magma body that was a source for the most recent volcanic eruption in the Coso volcanic field [ Manley and Bacon , 2000]. From this evidence and results of other studies in the Coso Range, we interpret the source to be a leaking deep reservoir of magmatic fluids derived from a crystallizing rhyolite magma body.

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Journal of Geophysical Research B: Solid Earth Article

Source-reported bounding extent: 35.878501481359535° to 36.37116739197613° latitude; -117.98098801405847° to -117.59333738713559° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

C.W. Wicks, W. Thatcher, Francis C. Monastero, M.A. Hasting. 2001-07-10. Steady state deformation of the Coso Range, east central California, inferred from satellite radar interferometry. https://doi.org/10.1029/2001jb000298

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