Long-Term Earthquake Prediction (LTEP) for the Kuril–Kamchatka island arc, June 2019 to May 2024; Properties of Preceding Seismicity from January 2017 to May 2019. The Development and Practical Application of the LTEP Method

Abstract

This paper is concerned with results from ongoing work using the method of long-term earthquake prediction (LTEP) for the Kuril–Kamchatka island arc based on the seismic gap and seismic cycle patterns. We highlight the most important lines of research in the LTEP method during the preceding decade. A long-term forecast is provided using the basic method for the next 5 years, June 2019 through May 2024, for the most active part of the earthquake-generating zone in the region. The 20 segments of that zone have forecasts for the next 5 years, including the phases of the seismic cycle, the normalized rate of low-magnitude earthquakes (А₁₀), the magnitudes of moderate-size earthquakes that are expected to occur with probabilities of 0.8, 0.5, and 0.15, the maximum expected magnitudes and probabilities of great (М ≥ 7.7) earthquakes. This study continues the well-known work of S.A. Fedotov by examining space–time features of the regional seismic process for the period beginning 2017, including the great Near Islands (Aleutian) earthquake of July 17, 2017, M = 7.7. The results, as obtained here, corroborate a close relationship between the seismic process occurring in the segments that pose the highest earthquake hazard according to the LTEP and the great earthquakes in the region itself and in the adjacent seismic areas, as well as emphasizing a very high earthquake hazard for several areas at the Kuril–Kamchatka island arc; Thus it is necessary to continue and expand the ongoing work in earthquake strengthening and enhancing the level of seismic safety in those areas under the highest hazard, including the administrative center of Kamchatka Krai, the town of Petropavlovsk-Kamchatsky.