COOPERATIVE SEISMIC HAZARDS MAPPING IN THE EVANSVILLE, INDIANA METROPLITAN AREA, USA

WILLIAMS, D.A., COUNTS, R.C., ANDREWS, W. M., Kentucky Geological Survey, University of Kentucky, Lexington, KY 42420 USA, williams@uky.edu,

counts@uky.edu, wandrews@uky.edu.

Evansville is the focus of a USGS seismic hazard-mapping project that has provided opportunities for cooperative research. The proximity of the Wabash Valley and New Madrid Seismic Zones to this populated area makes seismic hazard maps essential for mitigation. The scope of cooperating government agencies, academic departments, private companies and individuals presents its own communication and organizational problems, but thus far reasonable progress has been made. Geologic and seismologic interests brought together in these investigations include USGS mappers, Kentucky Geological Survey mappers, USGS seismologists, KGS seismologists, Central United States Earthquake Consortium State Geologists, and researchers from Purdue University and the Indiana Geological Survey. Among the products will be maps of surface and subsurface geology, geological and geotechnical databases, and earthquake liquefaction susceptibility and ground motion maps (including both scenario and probability maps). The project is done in consultation with an Advisory Committee consisting of professionals from the Evansville area. Mapping of the surficial geology for the study area is nearly complete. Current efforts are focused on developing the geologic and geotechnical databases needed for the seismic mapping. There have been numerous seismic profiles detailing the cross sections of filled paleovalleys and determining shear wave velocities. Funding from the USGS has supported much of the research, including funding meetings for researchers and the project Advisory Committee, geologic mapping through both State Map and Fed Map, conventional drilling, cone penetrometer testing, and age dating of samples. Local efforts led by the Building Commissioner of Evansville, the Southwest Indiana Disaster Resistant Community Corp., and state surveys have led to other cooperative programs. The most recent effort is to involve the Federal Emergency Management Agency and the Polis Center of the Indiana University Purdue University at Indianapolis in conducting a level 2.5 HAZUS analysis. This analysis will utilize data assembled through the current seismological and mapping studies.