Memory in the Occurrence of Earthquakes

摘要: We study the statistics of recurrence times $\ensuremath{\tau}$ between earthquakes above a certain magnitude $M$ in six (one global and five regional) earthquake catalogs. find that distribution strongly depends on previous time ${\ensuremath{\tau}}_{0}$, such small large tend to cluster time. This dependence past is reflected both conditional mean residual until next earthquake, which increase monotonically with ${\ensuremath{\tau}}_{0}$. As consequence, risk encountering event within span after last significantly past, an effect has be taken into account any effective prognosis.