Constraining Fault Displacements for Strike-slip Events using Physics-Based Simulations

Yongfei Wang, & Christine A. Goulet

Submitted November 5, 2021, SCEC Contribution #11727

Coseismic fault displacements in large earthquakes have caused significant damage to structures and lifelines located on or near fault lines. For distributed infrastructure systems that cannot avoid active faults, engineering displacement demands are defined using probabilistic fault-displacement hazard analyses (PFDHA). However, current PFDHA models are sparse and poorly constrained in part due to the scarcity of the observations. The physics-based dynamic rupture simulation method is an attractive alternative to address this important issue. Because fault displacements can be simulated for various geologic conditions as constrained by current knowledge about earthquake processes, they can be used alone or combined with empirical datasets to support PFDHA model development. Simulations must first be validated against data, then the underlying physics can justify their extrapolation to other events. This paper summarizes our calibrated dynamic rupture models and validation against observations of generic scaling relationships for strike-slip earthquakes (e.g., maximum and average displacements varying with magnitudes). This combination of calibration and validation of the model is critical to its use for the forward modeling of events we haven’t experienced yet. Our validation and extrapolation exercise paves the way for dynamic rupture modeling to quantitatively address fault-displacement hazard on a broader scale.

Citation
Wang, Y., & Goulet, C. A. (2021, 11). Constraining Fault Displacements for Strike-slip Events using Physics-Based Simulations. Oral Presentation at the 12th National Conference on Earthquake Engineering.