Mapping Liquefaction-Induced Ground Failure Potential

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.