摘要
Constraints provided by field observation, laboratory experiments and seismic data have lead to a general consensus that the shallow crust deforms by brittle faulting, while the lower crust deforms by crystal plastic flow. Studies of deformation mechanisms of minerals in faults have indicated that brittle-plastic transition of some faults occurred in the same depth (temperature and pressure) and this phenomenon is due to the strain rate. The presence of high-pressure fluid in active fault at depth is proved by analysis of characteristics of fault fluids, and these fluids, which can evolve in pressure pertaining to fracturing and sealing processes, play a key role during the seismic cycle. The formation of high-pressure fluid (cracks sealing) has several mechanisms, but researches show pressure solution deposition is one of the main mechanisms. Studies on pressure solution under the action of water can supplement and correct the crustal strength profile defined by traditional relations describing brittle/frictional behavior (Byerlee’s law) and dislocation creep.