This research is to extend a newly developed statistical tomography method to study velocity heterogeneities of different tectonic units of the crust and upper mantle under California. This method, developed by the Principal Investigator and collaborators, is termed Stochastic Tomography and leads to a better depth resolution of heterogeneity of seismic velocities. The method will be applied to seismic data of the CALNET in northern California and the SCARLET in southern California. By means of this method, study of the crust and upper mantle beneath the seismically active regions should refine knowledge of the tectonic structures at levels below what has been possible in the past. This research is a component of the National Earthquake Hazard Reduction Program.
