Long-term memory in the temporal statistics and depletion of spatiotemporal clustering of Japanese and Southern Californian earthquake occurrences

Abstract

Recent studies of seismicity suggests the occurrence of independent earthquakes after a very high finite number of events. Here, we investigate the statistical distributions of Japanese and Southern Californian earthquakes for k intervening events. We observed that for long separation distances, the distributions follow that of a random sequence, while waiting time distributions show prominent deviations from the random sequence. Waiting time and separation distance correlations were also observed to have limitations in the number of succeeding occurrences, suggesting long-term memory retainment for temporal statistics and spatiotemporal clustering depletion of Japanese and Southern Californian seismicity.