HR: 08:15h
AN: NG31A-02    [Abstracts]
TI: On Earthquake Statistics: Fault and Seismicity Models, ETAS and BASS
AU: * Holliday, J R
EM: holliday@cse.ucdavis.edu
AF: Center for Computational Science and Engineering, University of California One Shields Avenue, Davis, CA 95616, United States
AU: * Holliday, J R
EM: holliday@cse.ucdavis.edu
AF: Department of Physics, University of California One Shields Avenue, Davis, CA 95616, United States
AU: Van Aalsburg, J
EM: jvan@cse.ucdavis.edu
AF: Center for Computational Science and Engineering, University of California One Shields Avenue, Davis, CA 95616, United States
AU: Van Aalsburg, J
EM: jvan@cse.ucdavis.edu
AF: Department of Physics, University of California One Shields Avenue, Davis, CA 95616, United States
AU: Turcotte, D L
EM: turcotte@geology.ucdavis.edu
AF: Department of Geology, University of California One Shields Avenue, Davis, CA 95616, United States
AU: Rundle, J B
EM: jbrundle@ucdavis.edu
AF: Center for Computational Science and Engineering, University of California One Shields Avenue, Davis, CA 95616, United States
AU: Rundle, J B
EM: jbrundle@ucdavis.edu
AF: Department of Physics, University of California One Shields Avenue, Davis, CA 95616, United States
AU: Rundle, J B
EM: jbrundle@ucdavis.edu
AF: Department of Geology, University of California One Shields Avenue, Davis, CA 95616, United States
AB: There are two fundamentally different approaches to assessing the probabilistic risk of earthquake occurrence. The first is fault based. The statistical occurrence of earthquakes is determined for mapped faults. The applicable models are renewal models in that a tectonic loading of faults is included. The second approach is seismicity based. The risk of future earthquakes is based on the past seismicity in the region. These are also known as cluster models. An example is the epidemic type aftershock sequence (ETAS) model. In this paper we discuss an alternative branching aftershock sequence (BASS) model. In the BASS model an initial, or seed, earthquake is specified. The subsequent earthquakes are obtained from statistical distributions of magnitude, time, and location. The magnitude scaling is based on a combination of the Gutenberg-Richter scaling relation and the modified Båth's law for the scaling relation of aftershocks relative to the magnitude of the seed earthquake. Omori's law specifies the distribution of earthquake times, and a modified form of Omori's law specifies the distribution of earthquake locations. Unlike the ETAS model, the BASS model is fully self-similar, and is not sensitive to the low magnitude cutoff.
DE: 4475 Scaling: spatial and temporal (1872, 3270, 4277)
DE: 7209 Earthquake dynamics (1242)
DE: 7223 Earthquake interaction, forecasting, and prediction (1217, 1242)
SC: Nonlinear Geophysics [NG]
MN: 2007 Fall Meeting