Dealing With The Complexity of The M7.2 2010 El - Mayor Cucapah Earthquake

Christodoulos Kyriakopoulos, Gareth J. Funning, David D. Oglesby, John M. Fletcher, & Kenny J. Ryan

Published 2015, SCEC Contribution #7076

The M7.2 2010 El Mayor Cucapah earthquake (EMC) is a complex and unusual multi-segment event offering the opportunity to shed light on the mechanical behavior of faults as either individual segments or part of a more complex system. Although the dynamic behavior of individual faults is well studied, the cascade of smaller events into larger multi-segment events remains a matter of much discussion, including how faults interact with each other, and most importantly, what it takes to have them break in sequence. Reproducing the complex rupture of the 2010 EMC earthquake using dynamic models is not an easy task. Indeed, geologic observations, in contrast with what was originally suggested from combined seismological and geodetic models, revealed much more complexity (e.g., surface dip angles and discontinuous segments).The surface expression of the earthquake showed a complex pattern including minor ruptures. Here we present an effort to model as much possible of the complexity of this event. We have put together a Finite Element (FE) mesh that allow us to represent the complexity of the domain that hosted the rupture. The geometry of our fault is characterized by multiple stepovers and changes in dip and strike. In order to reproduce the slip pattern and complexity of the rupture we performed a full 3D dynamic analysis including and excluding the topographic relief of Sierra Cucapah and surroundings. Our simulations of the 2010 EMC event are part of a larger project that aims to combine dynamic models with observations from various sources (e.g. inverted slip distribution based on SAR interferometry) into a single model of slip.

Kyriakopoulos, C., Funning, G. J., Oglesby, D. D., Fletcher, J. M., & Ryan, K. J. (2015). Dealing With The Complexity of The M7.2 2010 El - Mayor Cucapah Earthquake. Poster Presentation at 2015 SCEC Annual Meeting.