Possible origin of memory in earthquakes: Real catalogs and an epidemic-type aftershock sequence model
Authors/Creators
- 1. Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion 84990, Israel 2Department of Physics, Bar Ilan University, Ramat Gan 52900, Israel 3 Potsdam Institute for Climate Impact Research, 14412 Potsdam, Germany 4School of Reliability and Systems Engineering, Beihang University, Beijing, 100191, China 5Science and Technology on Reliability and Environmental Engineering Laboratory, 100191 Beijing, China 6Institute for Regulation of Emergency and Disaster, Israel 7Geophysical Institute of Israel, Israel 8Istituto Nazionale di Geofisica e Vulcanologia, Rome, Italy
Description
Earthquakes are one of the most devastating natural disasters that plague society. Skilled, reliable earthquake
forecasting remains the ultimate goal for seismologists. Using the detrended fluctuation analysis (DFA) and
conditional probability (CP) methods we find that memory exists not only in inter-occurrence seismic records,
but also in released energy as well as in the series of the number of events per unit time. Analysis of a stan-
dard Epidemic Type Aftershock Sequences (ETAS) earthquake model indicates that the empirically observed
earthquake memory can be reproduced only for a narrow range of model’s parameters. This finding, therefore
provides tight constraints on the model’s parameters and can serve as a testbed for existing earthquake forecast-
ing models. Furthermore, we show that by implementing DFA and CP results, the ETAS model can significantly
improve the short term forecasting rate for the real (Italian) earthquake catalog.