High Temperature Silicified Zone as a Potential Caprocks for Supercritical Geothermal Reservoir

A supercritical geothermal reservoir is a promising energy resource for the future. The previous researchers have studied the availability of such a reservoir, including the presence of fluid and the permeability. However, the characteristic of cap-rock as an entrapment structure of the heat is yet to be known. Silica is the most abundant material in the earth's crust, and its solubility in water is dependent on the pressure and temperature. Silica in the form of quartz commonly occurs as veins, whether it generated from the up-flow of the deep-seated fluid trough the fracture network or the diffusion from the host rock. It is also found in the form of a narrow zone or lenses of relatively impermeable rock as cement at the transition between brittle and plastic zone. In this study, we research the silicified zone in the porphyry-Cu deposit as a potential caprock for a supercritical geothermal reservoir.