The Stress Accumulation Method and the Pattern Informatics Index: Complementary Approaches to Earthquake Forecasting

In this work, we provide a joint study of the stress accumulation method (SAM) (KING and BOWMAN, 2003) and the Pattern Informatics (PI) index (TIAMPO et al., 2002b). We examine the theoretical underpinnings for the similarities between the two techniques, as well as the differences in their application. The SAM technique is employed to determine likely mechanisms for smaller areas of increased probability identified by the PI index, while a modified version of the PI index can be used to locate regions where the smaller magnitude associated with the anomaly is below the resolution of the SAM. Finally, we present three case studies from different regions of the San Andreas fault system to illustrate both their complementary nature, as well as the advantages to combining them in one synthesized analysis.