Local and global stress fields for cause of tectonic earthquakes

Abstract

This paper will present a mechanical model of local and global stress fields in crustal rocks and/or hot mantle geo-materials. The local stress field is generated by highly compressed methane gas accumulated in the apertures of deep and tectonic faults or the voids or gaps of crustal rock masses and/or hot mantle geo-materials. The global stress field is generated by gravity and/or movements of tectonic plates. Specific equations for the local and global stress field are presented using some well established mechanical theory of solid materials. Parametric analyses of these equations are given to show the similarity and differences of the two stress fields and their combined effect. These results will be used to explain and interpret the observed phenomena of tectonic earthquakes. In particular, the mechanical and numerical results are further used to understand the consensus of unpredictability of damaging earthquakes with technology and measurement of some believed precursors under the current elastic rebound theory of active faults for the cause of earthquakes. These results can give us some clues to revise the current consensus and enhance the predictability of damaging earthquakes. The reasons are presented and examined for methane gas (CH4) to be the gas causing tectonic earthquakes.