Furlong 9628347 Active plate boundary tectonism involves a number of geophysical and geodynamical plate boundary processes, not all of which are well understood. Improving our understanding of the tectonic behavior of major plate boundaries in continental regions requires answering a broad range of questions, including: what is the interaction and coupling between upper crustal seismogenic processes and lower crustal mantle deformation?, how does the evolving thermal region affect the distribution of strain?, how does crustal heterogeneity affect patterns of deformation? and what is the origin of structures in these settings. The large amounts of data on the San Andreas Fault system coupled with advances in modeling makes progress on these fundamental questions feasible. Results are expected to clarify the important parameters involved in predicting plate boundary deformation as well as significantly improve understanding of the San Andreas system.