Earthquake Rupture Dynamics in Complex Geometries using Coupled Summation-By-Parts High-order Finite Difference Methods and Node-Centered Finite Volume Methods
2012 (English)In: Souther California Earthquacke Center, Annual Meeting, 2012Conference paper, Poster (Other academic)
We present a 2-D multi-block method for earthquake rupture dynamics in complex geometries using summation-byparts (SBP) high-order nite di-erences on structured grids coupled to nite volume methods on unstructured meshes. The node-centered nite volume method is used on unstructured triangular meshes to resolve earthquake ruptures propagating along nonplanar faults with complex geometrical features. The unstructured meshes discretize the fault geometry only in the vicinity of the faults and have collocated nodes on the fault boundaries. Away from faults, where no complex geometry is present, the seismic waves emanating from the earthquake rupture are resolved using the high-order nite di-erence method on coarsened structured grids, improving the computational e ciency while maintaining the accuracy of the method.
In order for the SBP high-order nite di-erence method to communicate with the node-centered nite volume method in a stable manner, interface conditions are imposed using the simultaneous approximation term (SAT) penalty method. In the SAT method the interface conditions and boundary conditions are imposed in a weak manner.
Fault interface conditions (rate-and-state friction) are also imposed in a provably stable manner using the SAT method. Another advantage of the SAT method is the ability to impose multiple boundary conditions at a single boundary node, e.g., at the triple junction of a branching fault.
The accuracy and stability of the numerical implementation are veried using the method of manufactured solutions and against other numerical implementations. To demonstrate the potential of the method, we simulate an earthquake rupture propagating in a nonplanar fault geometry resolved with unstructured meshes in the fault zone and structured grids in the far-eld.
Place, publisher, year, edition, pages
Hybrid FDM FVM finite difference finite volume summation-by-parts SBP SAT simultaneous approximation term penalty procedure nonlinear boundary conditions earthquake rupture dynamics branching faults antiplane
IdentifiersURN: urn:nbn:se:liu:diva-81441OAI: oai:DiVA.org:liu-81441DiVA: diva2:552893
2012 SCEC Annual Meeting, September 9-12, Palm Springs, California, USA