HR: 11:40h
AN: S42B-05 INVITED     [Abstracts]
TI: Accelerating Regional Seismicity and Earthquake Forecasting in California and Indonesia
AU: * Bowman, D D
EM: dbowman@fullerton.edu
AF: California State university - Fullerton, 800 N. State College Blvd, Fullerton, CA 92834-6850 United States
AU: Colella, H
EM: hcolella@gmail.com
AF: California State university - Fullerton, 800 N. State College Blvd, Fullerton, CA 92834-6850 United States
AU: King, G
EM: king@ipgp.jussieu.fr
AF: Institut de Physique du Globe de Paris, 4, place Jussieu Cedex 05, Paris, 75252 France
AB: It has been suggested that large earthquakes are preceded by a systematic increase in the level of background seismicity in a broad region around the impending event. This rate change, known as "accelerating moment release" (AMR), has been proposed as a precursory signal that could be used to forecast large earthquakes. Bowman and King [GRL, 2001] demonstrate that the pre-mainshock stress field, as indicated by a simple backslip model of the event, can be used to define the critical region that optimizes the precursory AMR signal. The observation of accelerating seismicity within this region represents a period of increased likelihood of a large earthquake. While this procedure has been used by various workers as a technique for a posteriori investigation of seismicity rate changes before large earthquakes, it can also be applied prospectively. In a predictive capacity, the AMR search is conducted using the pre-event stress field for a hypothetical earthquake scenario with a size and slip distribution consistent with geologic and geodetic evidence of the fault behavior. This work examines the practical application of AMR as a tool for earthquake rupture forecasts on the years-to-decades timescale. The approach is applied specifically to both the San Andreas fault system in California and the Sumatra/Java subduction zone.
DE: 7223 Earthquake interaction, forecasting, and prediction (1217, 1242)
DE: 7230 Seismicity and tectonics (1207, 1217, 1240, 1242)
SC: Seismology [S]
MN: Fall Meeting 2005