Earth's Crust Faults Density and Thermal Springs in the Seismic Activity Migration Zone at the Amutsky Swarm Region
Based on the total seismic energy spatial-temporal analysis of the Amurskiy swarm region, seismic activity slow migration trend (months and years) was fixated along zones of high faults density, characterized by the hydrothermal springs. We present the possible seismic activity propagation mechanism with groundwater participation, that take part in stress transter by pore pressure change in in the fractured zone, could be one of the triggers of earthquakes, and could decrease seismic events force. The Amutsky swarm as a source of stress state initial change facilitated the stresses release in the seismic area and the stress transfer to the more plastic layers of the lithosphere: the lower crust and the upper mantle, transmitting stress slowly than the upper crust due to rheological properties. The stress state change front propagation causes an increase of fluids pore pressure in the upper and lower crust, migrating upward along the least resistance path – by the fracture systems. Increased terrestrial heat flow values at the migration seismic process zone correspond to an increase of the plastic properties in the lower crust, that take part in stress transfer process. High faults density of the Amutsky swarm region contributes to the water permeability of the upper earth's crust elastic layer and stress relaxation.
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