Dynamic Models of Large Ruptures on the Southern San Andreas Fault

Julian C. Lozos

Submitted August 15, 2016, SCEC Contribution #7044, 2016 SCEC Annual Meeting Poster #061

The southern San Andreas Fault is a heterogeneous structure. Despite being a primary plate boundary fault, it has major geometrical complexities in the Big Bend and San Gorgonio Pass, and also shows substantial variation in maximum horizontal stress orientation along strike. The earthquakes of 1857 and 1812 may have had at least one rupture endpoint at a point of stress or geometrical complexity, and paleoseismic records suggest that many prehistoric events also exhibit geometrical segmentation. However, the possibility of a rupture from Cholame to the Salton Sea is allowed by paleoseismic records and multi-cycle models, and is considered in hazard assessment. In this study, I use the 3D finite element method to conduct models of dynamic rupture on the entire southern San Andreas Fault. I implement stress orientations from seismicity literature, but vary initial stress amplitudes in order to determine which values are necessary to replicate historic or well-documented paleoseismic ruptures, as well as which values and nucleation locations are necessary to produce a wall-to-wall rupture.

Key Words
San Andreas Fault, dynamic rupture, fault geometry, rupture dynamics, rupture modeling, Big Bend

Citation
Lozos, J. C. (2016, 08). Dynamic Models of Large Ruptures on the Southern San Andreas Fault. Poster Presentation at 2016 SCEC Annual Meeting.


Related Projects & Working Groups
Fault and Rupture Mechanics (FARM)