An Energy-Dependent Earthquake Moment–Frequency Distribution

ABSTRACT The magnitude–frequency distribution (MFD) of many earthquake catalogs is well described by the Gutenberg–Richter (GR) law or its tapered version (TGR). This usually extrapolated to any subsets space–time window covered catalog. However, some empirical observations and logical thoughts may raise doubts about validity this extrapolation. For example, according elastic rebound theory, we assert that probability a strong shock nucleating within short-time interval in small area A just ruptured another event should be lower than expected GR (or TGR): lot energy has already been released, it takes time recover previous state. Here, put forward modification TGR, named energy-dependent TGR (TGRE) which corner seismic moment becomes time-varying function depending on (1) conceivable strongest nucleate A; (2) elapsed since last reset residual value; (3) rate recovery, linked recurrence fault(s) involved. model also verifies an invariance condition: for large windows, occurrence does not affect significantly whole available, is, TGRE TGR. simple rooted clearly stated assumptions. To evaluate reliability applicability, apply 1992 Landers sequence. As TGRE, find MFD close fault system interested mainshock (Mw 7.3) differs from earthquakes off-fault, showing magnitude. We speculate profitably used operational forecasting explains observation aftershocks always outside fault.