Seismicity rate modeling for prospective stochastic forecasting: the case of 2014 Kefalonia, Greece, seismic excitation
We examined the January–February 2014 earthquake doublet (M w = 6.1 and M w = 6.0) and the associated aftershocks which form a seismic excitation adequately well recorded by a dense local seismological network. It started on January 26 with the main shock, causing a lot of panic and followed by numerous aftershocks. The second main shock with M w = 6.0 occurred 7 days later on an along-strike adjacent fault segment. The close proximity of the two main shocks, in both space and time and the intense aftershock sequence, triggered the investigation of the occurrence probability evolution for the stronger aftershocks and possibly a third main shock in the seismic excitation. This purpose was further motivated by the potential of the area for hosting a stronger (M w ≥ 6.0) earthquake based upon both historical information and instrumental data. Aftershock rate modeling was done on subsequent data samples by the restricted epidemic-type aftershock sequence stochastic model, and probabilities for the occurrence of strong (M w ≥ 5.0) earthquakes were calculated during the progress of the aftershock sequence. We executed daily model simulations and probability forecasts for 30 days focusing in more detail on the impact of some model parameters on the prospective forecasting. Trying to be near to a real-time case, all forecasts were done on data up to the moment of forecasting.
KeywordsSeismicity Aftershock sequence Aftershock probabilities Kefalonia (Greece) RETAS stochastic model
This work was partially supported by the OTRIONS project “Multi-Parametric Network for the Study and Monitoring of Natural Hazards in the Otranto Channel and the Ionian Sea.” Some plots were made using the Generic Mapping Tools version 4.5.3 (www.soest.hawaii.edu/gmt, Wessel and Smith 1998). Geophysics Department Contribution 842.
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