Spontaneous Rupture Sequences on Non-Planar Elastodynamic Faults: The Interaction of Geometrical Hetergeneities and Stress Heterogeneities and the Observable Consequences

Abstract for proposal EAR0087645 (PH #27x)

PI's: B. Shaw

Title: Spontaneous Rupture Sequences on Non-Planar Elastodynamic Faults: The Interaction of Geometrical Heterogeneities and Stress Heterogeneities and the Observable Consequences

Geometrical and material heterogeneities of faults have long been viewed as crucial features that affect earthquake behavior. Recently the role of stress heterogeneities has begun to be recognized as a potentially central feature, particularly with the demonstration that stress heterogeneities alone already can produce a remarkably rich and complex set of earthquake-like behaviors on uniform planar faults. What is missing is an understanding of how the two types of heterogeneities, the static geometrical and material heterogeneities, and the dynamic stress heterogeneities, might combine and interact to produce even more realistic earthquake behavior. This research is developing a new approach to modeling geometrically heterogeneous faults. This approach can simulate the unexplored realm of sequences of elastodynamic events on nonplanar faults. Research focuses on applying the models, which involve interactions of stress and geometrical heterogeneities, in ways that are both significant and potentially observable.