The Long-Term Earthquake Prediction for the Kuril–Kamchatka Island Arc for the April 2016 through March 2021 Period, its Modification and Application; the Kuril–Kamchatka Seismicity before and after the May 24, 2013, M 8.3 Deep-Focus Earthquake in the Sea of Okhotsk

Abstract

This paper discusses results from ongoing research on long-term earthquake prediction for the Kuril–Kamchatka island arc based on the concepts of seismic gaps and the seismic cycle. We developed a forecast for the next 5 years (April 2016 through March 2021) for all segments of the earthquake-generating zone along the Kuril–Kamchatka arc. The 20 segments of the arc were analyzed to develop forecasts of the appropriate phases of the seismic cycle, a normalized parameter of the rate of small earthquakes (A10), the magnitudes of moderate earthquakes that are expected with probabilities of 0.8, 0.5, and 0.15, the maximum expected magnitudes, and the probabilities of great (M ≥ 7.7) earthquakes. We discuss the seismic process in the Kuril–Kamchatka earthquake-generating zone before and after the deep-focus May 24, 2013 M 8.3 earthquake in the Sea of Okhotsk. The results corroborate the high seismic hazard in the area of Petropavlovsk-Kamchatskii and the urgent need for continuing with and expanding the ongoing work of seismic retrofitting and seismic safety enhancement. We quote practical results from applications of the method during 30 years.