The paper considers an aftershock process caused by an Mw = 6.1 earthquake which occurred on 21 February 2008 in the Storfjord channel Spitsbergen). The earthquake was the strongest in the history of seismic monitoring on the Barents Sea shelf. To study the aftershock process, some relaxation models of aftershock decay rate and the Epidemic-type Aftershock-sequences ETAS model of triggered seismicity were fitted. It was shown that the aftershock process was a superposition of two subprocesses relaxation and trigger. Each of the subprocesses was simulated using a relevant model. Based on the modeling, a hypothesis of Storfjord seismicity connected with fluid effect on the local stress field was suggested.
Aftershock process, model of aftershock decay rate, ETAS model, aftershock process simulating, Spitsbergen
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