SEISMIC AND LIQUEFACTION HAZARD MAPS FOR LAKE COUNTY, NORTHWESTERN TENNESSEE

A five-year seismic and liquefaction hazard mapping project for five western Tennessee counties began in 2017 under a Disaster Resilience Competition grant from the U.S. Department of Housing and Urban Development to the State of Tennessee. The project supports natural hazard mitigation efforts in these five counties. The seismic hazard maps for Lake County in northwestern most Tennessee are being completed in early 2018. Additional geological, geotechnical, and geophysical information has been gathered in Lake Co. to improve the base northern Mississippi Embayment hazard maps of Dhar and Cramer (2017). Information gathered includes additional geological and geotechnical subsurface exploration logs, water table level data collection and measurements, new measurements of shallow and deep shear-wave velocity (Vs) profiles, and the compilation of existing Vs profiles in and around the county. Improvements are being made in the 3D geological model, water table model, the geotechnical liquefaction probability curves, and the Vs correlation with lithology model for Lake Co. Resulting improved soil response amplification distributions on a 1 km grid will be combined with the 2014 U.S. Geological Survey seismic hazard model (Petersen et al., 2014) sources and attenuation models to add the effect of local geology for Lake Co. Resulting products will be similar to the Memphis and Shelby County urban seismic hazard maps recently updated by Cramer et al. (2018).