Report GIRS 2022-07: Surface Fault Displacement Models for Strike-Slip Faults

By: Chiou, Brian S.J.; Chen, Rui ; Thomas, Kate; Milliner, Christopher W.D.; Dawson, Timothy E.; and Petersen, Mark D.
DOI: 10.34948/N3RG6X

Abstract: Fault displacement models (FDMs) are an essential component of the probabilistic fault displacement hazard analyses (PFDHA), much like ground motion models in the probabilistic seismic hazard analyses for ground motion hazards. In this study, we develop several principal surface FDMs for strike-slip earthquakes. The model development is based on analyses of the new and comprehensive fault displacement database developed as part of the Fault Displacement Hazard Initiative project led by the University of California, Los Angeles. The main objective of our study is to update the FDMs that were developed over a decade ago by the U.S. Geological Survey and California Geological Survey, in which a reference trace was drawn manually, FDMs are fixed-effect models for lateral displacement, displacement on multiple subparallel ruptures is not aggregated, magnitude (M) scaling is linear, and natural logarithm of displacement is assumed to be normally distributed.