Diagnosing the precatastrophic state of the environment in a subduction zone prior to very strong mega-seismic events

Abstract

The barrier-free seismic process in the subduction zone is considered. The Kurils–Kamchatka subduction zones are characterized by two major environments of oscillatory processes expressed in seismic events distributed long-term throughout the zone and concentrated short-term in a local regional area. The first environment is related to the background seismic process. The fast localization of processes confirms the idea of synchronous movement of regional environment components and is indicative of precatastrophic conditions in the zone. Diagnosis of precatastrophic conditions in the zone makes it possible to control the transition from the background seismic process to the short-term regime of the most likely very strong seismic events. A short-term forecast of the epicentral area of the strongest mega-seismic events in subduction zones is implemented.