This action is a follow on to NSF CES-8708747, which concerns an investigation of the stiffness loss in sands following a dynamic disturbance. On July 24, 1987, such a disturbance occurred during seismic oil prospecting, initiating a road embankment slide and subsequent roadway collapse on Highway 94 in Michigan's Upper Peninsula, twelve miles west of the city of Munising. This incident has the potential to generate valuable data relevant to the original award. The incident occurred during standard seismic reflection profiling. Six 22 ton trucks were generating seismic signals for a reflection study by vibrating the road surface. It is believed that the flow slide was initiated by a liquefaction type failure. Shortly after the incident, Prof. Hryciw performed the necessary field reconnaissance and obtained the relevant information and data. This data are now being analyzed. It is expected that valuable information relevant to the reduction in stiffness of cohesionless soils due to earthquake loading can be extracted from the data obtained as a result of this seismic profiling incident.