Slip Rates of the North American and Pacific Plates along the San Andreas Fault Using GPS Data

Event Center BC

Global Positioning System (GPS) site velocities were utilized to reveal the nature of deformation along the boundary between the North American Plate and the Pacific Plate. The velocities of survey benchmarks measured using GPS were used to conduct elastic halfspace modeling an transect across the plate boundary near Bakersfield, California. The San Andreas Fault, as well as several other prominent faults, were studied to further develop a broad understanding of the relationship between the two plates. There were 29,161 slip rate combinations of six faults that were tested to see which would provide the best fit to the observed site velocities. The San Andreas Fault was the fault with greatest slip rate (35 mm/yr) in the best fit model with a range of possible slip rates from 31 mm/yr to 44 mm/yr. The Owen’s Valley Fault had a best fit slip rate of 5 mm/yr with a range of possible slip rates from 0 mm/yr to 16 mm/yr. The Northern Death Valley Fault also had a slip rate of 5 mm/yr in the best fit model and had a range of 0 mm/yr to 8 mm/yr. The remaining faults and their best fit slip rates were the Hunter Mountain Fault at 3 mm/yr, the Hosgri Fault at 1 mm/yr, and the West Huasna Fault at 0 mm/yr.