Statistics and Correlations of Seismic and Tectonic Moment Rate in California and the Great Basin

The largest regional earthquakes provide the most significant contribution to the earthquake-related damage, they also responsible for the most of the long-term regional seismic moment release. Thus, in order to develop physically based earthquake hazard assessments, one should be able to connect the moment rate from the observed seismicity to its long-term predictions based on geodetic and geological information. We study here a most detailed spatial distribution of geodesy- and geology-based expected moment rate in California and the Great Basin (see Blewitt et al., "GPS Velocity and Strain Rate Fields in the Great Basin and California", Session G2) and compare it with the observed seismic moment rate on different temporal and spatial scales. The comparison clearly demonstrates a moment deficiency at intermediate and small spatial scales that can be explained, at intermediate scales, by the heavy-tailed Pareto distribution of seismic moment and the typically short time-span of catalogs. On short spatial scales the observed moment deficiency is significantly larger than that predicted by a simple Pareto model. We present a statistical framework for studying these and other related phenomena connected with the seismic moment release.