Permeability change generated by silica dissolution-precipitation on granite fracture surface in hydrothermal conditions.

Abstract

Fractures provide significant influences on transport of energy and heat. We conducted hydrothermal flow through experiments using pure water and silica supersaturated solution to reveal a porosity structure and permeability evolution during the dissolution-precipitation in granite fracture. In dissolution experiments, local dissolution of Qtz Gouges made some flow paths and increase fracture permeability. In precipitation experiments, silica precipitation strongly decreased the permeability.