This research is to map Pn and Sn seismic velocities undercontinental plateaus in a number of major regions of lithosphericplate convergence in the world. The method will use theextensive 22.year ISC database and apply tomographic techniquesto confirm and further delineate lateral variations of seismicvelocity. This work is an extension of similar detailed mappingof Pn velocities beneath the Colorado plateau now underway. These results will serve as constraints to dynamic models of thetectonics of plate convergence regions. The high level ofearthquake activity in plate convergent regions makes thisresearch an important contributor to models of earthquakeoccurrence there and, thus, this work is a contributor to theNational Earthquake Hazard Reduction Program.
