Ground Motion Amplification of Soils in the Upper Mississippi Embayment

摘要

The 1811-1812 New Madrid earthquakes affected a large area in the CentralUnited States. The seismic hazard is low since large-magnitude earthquakes such asthese are infrequent. However, the seismic risk is considerable due to the geology andbuilding codes that do not adequately reflect the seismic hazard. The strong groundmotions observed during the 1811-1812 earthquakes are attributed to the soft depositsand the deep soil column encountered in the Mississippi Embayment. This studyevaluated the effect of embayment deposits on dynamic site response. Remote sensingimagery was evaluated to identify soils susceptible to ground motion amplification.Regional and local shear wave velocity (Vs) profiles were developed to model conditionsat soil sites based on the age of near-surface geologic deposits.