Regional efficacy of a global geospatial liquefaction model

Abstract Liquefaction hazard maps are important for both pre- and post-event planning and mitigation. The global geospatial liquefaction model (GGLM) proposed by Zhu et al. (2017) and recommended for global application results in a liquefaction probability that can be interpreted as liquefaction spatial extent (LSE). The GGLM uses ShakeMap's PGV, topography-based Vs30, distance to water body, water table depth, and annual precipitation as explanatory variables. The GGLM was originally developed and validated across 23 global earthquakes with most of the earthquakes in coastal settings. In this paper, LSE maps have been generated for 29 earthquakes around the world in a wide range of settings in addition to 23 of the original events to evaluate the generality and regional efficacy of the model. The GGLM was found to overpredict liquefaction spatial extent for earthquakes with large areas experiencing low PGA (below 0.1 g) and as a result, the GGLM has been modified to decrease over-prediction with the addition of a PGA threshold (no liquefaction when PGA