Presenter: Ming-Kai Hsu
Date: 2015/10/15
Abstract
A time-dependent probabilistic seismic-hazard (PSH) model is important in loss assessments for insurance and risk management. In time-dependent models, the probability of earthquake occurrence increases with the elapsed time since the last large or characteristic earthquake on a fault or fault segment. Compared with the time-independent PSH model, time-dependent PSH model may be better at identifying the short-term risks for economic loss assessment. For the purpose of sensitivity testing and illuminating nonconsensus components of time-dependent models, the California Department of Conservation, Division of Mines and Geology (CDMG) has assembled a time-dependent version of its statewide probabilistic seismic hazard (PSH) model for California. The model incorporates available consensus information from within the earth-science community, except for a few faults or fault segments where consensus information is not available. For these latter faults, published information has been incorporated into the model. As in the 1996 CDMG/U.S. Geological Survey (USGS) model, the time-dependent models incorporate three multisegment ruptures: a 1906, an 1857, and a southern San Andreas earthquake. For expected damage and 10% in 50-year PGA hazard, changes between time-dependence and time-independence can exceed 20% within 20 km of the faults.
Reference