Endogenous activity of the Earth and decompression model of seismic noise

Abstract

In view of the challenges facing prognosis of large earthquakes, the nature of a seismic noise field (SNF) is considered. Taking into account the fact that the continuity and planetary scale of the SNF, as well as the SNF enhancement, when effected by exposures, cannot be explained by fracturing processes, a decompression mechanism of the SNF excitement is suggested. This mechanism is a component of the physicochemical seismicity model (Gufel’d, 2008). The conditions of SNF formation (taking high frequency noise recording as an example) due to continuous degassing, gas bubbling, and intensification of this process during decompression at depths of 200‐400 m are considered. A relation between the SNF diurnal variation and the effect of the natural electromagnetic field and its correlation with strong seismicity are shown. It was noted that elastic waves, accompanying decompression, will generate lythosphere-atmosphere‐ionosphere relations, followed by large earthquakes. Oscillations of the Earth’s crust surface structures with period ranging from seismoacoustic (less then 10 ‐3 sec) to microseismic (1‐10 2 sec and more) are referred to seismic noise fields (SNF). The intermediate range is referred to high-frequency seismic noise (HFSN, 10 ‐1 to 10 ‐3 sec). The current attention being