Barrier effect of degassing and destruction of the Earth’s crust

Doklady Earth Sciences -     

The reflection of geodynamic processes in local geoacoustic emissions

This paper is concerned with the correlation of fast local processes that generate geoacoustic emissions and the regional character of excitation in the geologic medium prior to large earthquakes. It is shown that this comparison is possible based on the unifying process of vertical energy transport due to the earth’s degassing. For the first time here, we examine local geoacoustic characteristics by analyzing Poincare diagrams and developing difference equations that describe dynamic changes in the characteristics of acoustic emission sources. Based on this concept, and incorporating the continuity of geoacoustic emissions, we suggest a decompressional model of seismoacoustic noise and geoacoustic emissions as a component of the noise.     

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

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.     

Physicochemical mechanics of large crustal earthquakes

We examine the geological factors that control the precursory processes of earthquakes and the occurrence of low-and high-magnitude seismicity. Degassing and mutual displacements of lithospheric blocks are under discussion as the leading factors. Three scenarios for seismotectonic processes are discussed, these scenarios incorporate the occurrence of physicochemical reactions in solids and fluids in three dimensions. The precursory processes of large crustal earthquakes are related to block boundaries being locked due to the physicochemical reactions. Possibilities for earthquake prediction and sesimicity modification are discussed.