Mapping Liquefaction-Induced Ground Failure Potential

TLDR

Ground failure opportunity occurs when seismic shaking is strong enough to produce liquefaction and ground failure in susceptible materials, and additional geotechnical studies are needed for site‑specific determinations within the map units. The study develops regional maps of liquefaction‑induced ground failure potential by integrating geologic and seismologic data with newly defined criteria. The potential map is created by merging a probabilistic ground‑failure opportunity map—derived from a correlation between earthquake magnitude, distance to liquefiable sites, and regional seismicity—with a susceptibility map based on sediment type and setting from Quaternary geologic maps. The resulting liquefaction‑induced ground failure potential maps aid planning, zoning, and decision making.

Abstract

Geologic and seismologic information is used in concert with criteria developed herein to make regional maps of liquefaction-induced ground failure potential. Two maps, a ground failure opportunity map and a ground failure susceptibility map, are combined to form the potential map. Ground failure opportunity occurs when seismic shaking is strong enough to produce liquefaction and ground failure in susceptible materials. A correlation between earthquake magnitude and maximum distance from energy source to possible liquefiable sites is used with maps of regional seismicity to prepare an opportunity map. The opportunity map has a probabilistic basis. Criteria relating liquefaction susceptibility to sediment type and setting are used with Quaternary geologic maps to derive the susceptibility map. Liquefaction-induced ground failure potential maps are useful for planning, zoning and decision making purposes. Additional geotechnical studies are required for liquefaction potential determinations at specific sites within the map units.