Book Description

"Earthquakes of engineering interest are normally considered to result only from slippage or movement along existing faults. Hence, the detection of existing faults and their assessment as active or inactive constitutes an essential aspect of earthquake design. Some faults in soft sediments, through active, may not have the capability of generating earthquakes and must be so interpreted. Active faults generally may be evaluated for their maximum capacity to generate earthquakes through a synthesis of the local geologic and seismic history and worldwide relationships between fault dimensions earthquakes. Major earthquakes are caused by slippage along large faults, which are unlikely to be missed in detailed geologic investigations for sites in western United States. This may not be the case in the central and eastern United States. Small faults may be missed in any investigation so that a floating earthquake of limited size must be assumed to account for them. When faulting is not manifest at the surface, seismic history and geologic investigations can define geographic limits or zones for which floating earthquakes of various sizes are assigned"--Page ix.