Thermal decompaction of rocks and its effect on permeability

Experimentally and theoretically there has been studied a decompaction of a large group of low permeable rocks under nongradient heating within temperature interval 25-700 C. Rock decompaction is characterized by forming a system of microcracks over grain boundaries. A set of formed microcracks results in an essential alteration of rock physical properties: considerable increase (by several orders) transport characteristics, porosity increase, elastic constants decrease. Granite permeability is experimentally defined in situ under the conditions of low effective pressure at T=20-600 C. The investigations carried out confirm a real possibility of a uniform percolation of solutions through massive rocks as a…