Tsunamis and splay fault dynamics

J. Wendt; D. D. Oglesby; E.L. Geist

doi:10.1029/2009gl038295

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Tsunamis and splay fault dynamics

J. Wendt·D. D. Oglesby·E.L. Geist

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Abstract

The geometry of a fault system can have significant effects on tsunami generation, but most tsunami models to date have not investigated the dynamic processes that determine which path rupture will take in a complex fault system. To gain insight into this problem, we use the 3D finite element method to model the dynamics of a plate boundary/splay fault system. We use the resulting ground deformation as a time-dependent boundary condition for a 2D shallow-water hydrodynamic tsunami calculation. We find that if me stress distribution is homogeneous, rupture remains on the plate boundary thrust. When a barrier is introduced along the strike of the plate boundary thrust, rupture propagates to the splay faults, and produces a significantly larger tsunami man in the homogeneous case. The results have implications for the dynamics of megathrust earthquakes, and also suggest mat dynamic earthquake modeling may be a useful tool in tsunami researcn. Copyright 2009 by the American Geophysical Union.

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J. Wendt, D. D. Oglesby, E.L. Geist. 2009-08-04. Tsunamis and splay fault dynamics. https://doi.org/10.1029/2009gl038295

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