New Insights on the Southern Coyote Creek Fault and Superstition Hills Fault

Afton Van Zandt and Robert J. Mellors
San Diego State University, 5500 Campanile Drive, San Diego, CA 92182

Recent field work has confirmed an extension of the southern Coyote Creek (CCF) branch of the San Jacinto fault in the western Salton Trough. The fault marks the western edge of an area of subsidence caused by groundwater extraction, and field measurements suggest that recent strike-slip motion has occurred on this fault as well. We attempt to determine whether this fault connects at depth with the Superstition Hills fault (SHF) to the southeast by modeling observed surface deformation between the two faults measured by InSAR. Stacked ERS (descending) InSAR data from 1992 to 2000 is initially modeled using a finite fault in an elastic half-space. Observed deformation along the SHF and Elmore Ranch fault is modeled assuming shallow (< 5 km) creep. We test various models to explain surface deformation between the two faults.

AAPG Search and Discovery Article #90076©2008 AAPG Pacific Section, Bakersfield, California