The phenomenon of earthquake fault rupture propagation through soil is
quite complex and is not well understood at this time. This paper pre
sents the results of an integrated investigation of this problem. Insi
ghts are developed from the examination of surface fault rupture field
case histories, laboratory physical model tests, and physical analogi
es to the earthquake fault rupture process. Field observations and exp
erimental results illustrate the ''typical'' patterns of behavior deve
loped in the soil overlying a base rock fault displacement. Evidence s
uggests that differential movement across the distinct fault rupture d
issipates as the fault rupture propagates toward the ground surface th
rough unconsolidated earth materials, and that the characteristics of
the soil overlying the bedrock fault strongly influence the observed e
arthquake fault rupture propagation behavior.