Johnson 9628644 The PIs propose to investigate the viscous properties of the crust by extending geodetic measurements made from 1969 through 1987 in the area of the 1968 Borrego Mountain earthquake (M=6.5). The PIs will collect an additional set of GPS observations in the area, and will use the resulting 28-year span of these measurements to determine the time-dependence in strain rate caused by fault afterslip and inelastic crustal rheology. This research will provide new data essential for the analysis of crustal viscosity and its relation to earthquake deformation.
