Change in Permeability in Fault Zones under Impact of Seismic Waves Induced by Massive Blasts
I. V. Shatunov1,2, G. G. Kocharyan1, A. A. Ostapchuk1,2
1Academician Sadovsky Institute of Geosphere Dynamics, Moscow, Russia
2Moscow Institute of Physics and Technology, Dolgoprudny, Russia
Keywords: Tectonic fault, blast-induced seismic effect, Biot slow-wave diffusion, colloids, pore pressure, permeability, fluid velocity
Abstract
Fine particles, when flowing with fluids in the Earth’s crust, can settle on surfaces of pores and fractures, and form colloid barriers which drastically reduce permeability of jointed media. When seismic waves travel in fault zones, which have greatly different stiffness as compared with enclosing rocks, Biot slow-wave diffusion originates, which can cause destruction of the colloid barriers, growth of permeability, redistribution of pore pressure and change in the stress-strain condition of a fault. This article describes the studies into conditions when regular seismic impacts induced by massive blasting can lead to a drastic change in the permeability in the fault zones.
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