Assessment of earthquake occurrence probability in Kamchatka region by seismological and complex ionospheric precursors

In this paper, based on the combination of medium- and short-term precursors, accompanying earthquakes generation, a methodology to assess the area, time period and probability of occurrence of strong earthquakes with KS≥13.5 (M≥6.0) in Kamchatka region is presented. As a medium-term precursor, the seismological parameter ξP is considered. It is obtained on the basis of a probabilistic model of the seismic regime and determines statistically significant deviations of the current probabilities Pk(Si) of seismic events with an energy class KS≥9.0 in the Si region from the long-term (background) values of the probabilities PT(Si). The earthquake waiting area was defined as a group of Si regions in which anomalies of the seismic regime were identified by the parameter ξP. A complex of ionospheric parameters is considered as short-term precursor with an earthquake waiting period of up to 5 days, they are: the K-layer, the sporadic Es layer of type r, the critical frequency foF2 and the stratification of the F2 layer by frequency. Based on the Bayesian approach, prognostic estimates were made for the occurrence probabilities of strong earthquakes with KS≥13.5 (M≥6.0) occurred during the period 2019-2021 in Kamchatka region in the waiting areas defined by the parameter ξP, provided that a complex of anomalous ionospheric parameters was identified. The work was carried out within the framework of implementation of the State Task AAAA-A21-121011290003-0.

Bogdanov V.V., Pavlov A.V. \\ Solar-terrestrial relations and physics of earthquake precursors: XII International Conference, Paratunka village, Kamchatka Krai, September 27 – October 01, 2021. collection of tez. dokl. – Paratunka: IKIR FEB RAS, 2021. pp.83-84.