Evaluating the information content in seismicity measures

Kristy F. Tiampo, William Klein, Abigail Jimenez, Shoshana Z. Kohen-Kadosh, & John B. Rundle

In Preparation 2007, SCEC Contribution #1083

In this work we use the Pattern Informatics (PI) index of Tiampo et al., 2002b in order to relate cascade-type models of earthquake seismicity to historic seismic catalog data. We analyze the occurrence of anomalous seismicity in the historic California catalog for the period 1978 through 2005 by discretizing the analysis into various magnitude bands. The results show that the different bands contain different information about the underlying stress field as it relates to the seismicity, and that information does not appear to cascade directly from smaller to larger events, or vice versa. We hypothesize that there is another mechanism operating on the stress field that the various magnitude bands are sensing to a different degree. Potential mechanisms that might produce this phenomena are likely related to both the geometric imposed by the structure of the fault network in conjunction with a nonstationary temporal effects with varying natural time scales.

Tiampo, K. F., Klein, W., Jimenez, A., Kohen-Kadosh, S. Z., & Rundle, J. B. (2007). Evaluating the information content in seismicity measures. Pure and Applied Geophysics, (in preparation).