This research is to resurvey a Global Positioning System (GPS) network measured by Caltrans in the Santa Cruz area to determine coseismic surface displacements in the October 17, 1989, Loma Prieta, California, earthquake. This data will be inverted along with other geodetic data available in the region to determine a coseismic slip model of the Loma Prieta earthquake. GPS monitoring will continue on an approximately quarterly basis to detect any post-seismic slip on the San Andreas or adjacent faults. This research is a component of the National Earthquake Hazard Reduction Program.
