Global Positioning System tracking of slip rate of the San Andreas fault

Event Center A & B

Using GPS data collected at various benchmarks in a transect across the Pacific-North American plate boundary through the eastern San Bernardino Mountains, slip rates were determined for the faults in that area. Possible slip rate combinations for thirteen faults along the North American and Pacific plate boundary were tested to determine which of these slip rate combinations best fit with observed GPS site velocities. An envelope was created to house an acceptable range of model predictions that fall among the observed velocities. The slip-rate models that fell into this acceptable range are as follows; 0-8 mm/yr for the San Andreas fault, with corresponding rates of 22 and 14 mm/yr, respectively, for the San Jacinto fault. The best-fitting model had 2 mm/year for the San Andreas fault and 20 mm/year for the San Jacinto fault.