EARTHQUAKE FAULT RUPTURE PROPAGATION THROUGH SOIL

The phenomenon of earthquake fault rupture propagation through soil is quite complex and is not well understood at this time. This paper presents the results of an integrated investigation of this problem. Insights are developed from the examination of surface fault rupture field case histories, laboratory physical model tests, and physical analogies to the earthquake fault rupture process. Field observations and experimental results illustrate the ''typical'' patterns of behavior developed in the soil overlying a base rock fault displacement. Evidence suggests that differential movement across the distinct fault rupture dissipates as the fault rupture propagates toward the ground surface through unconsolidated earth materials, and that the characteristics of the soil overlying the bedrock fault strongly influence the observed earthquake fault rupture propagation behavior.