9725709 Archuleta This research involves the investigation of dynamic earthquake fault rupture by means of state-of-the-art finite element computer codes. Earthquake fault rupture is a very complex physical phenomenon that is currently an active area of study in the seismological community. Ground motion recordings during many recent earthquakes have emphasized that an understanding of the dynamics of earthquake fault rupture is crucial in understanding the observed ground motion, especially on the hanging wall of dip slip faults. In particular, in the case of non-vertical faulting, the complicated interaction between seismic waves and the rupture process may lead to profound effects in the rupture propagation and resultant ground motion. Many studies have attempted to create analytical or numerical models of earthquake fault rupture, but most have required extensive simplifications and approximations to make the dynamic equations solvable. The finite element method will be used to advance our understanding of strong motion as affected by the free surface for a dipping fault, and as affected by the particular friction law used in the modeling. This research is a component of the National Earthquake Hazard Reduction Program. ***
