Fracturing and Episodic Fluid Expulsion in Pressure Compartments  

作　　者：Mei Lianfu Department of Petroleum Geology, China University of Geosciences, Wuhan 430074 Wang C.Y. Department of Geology and Geophysics, University of California, Berkeley 94720 Cai Yongen Department of Geology, Peking University, Beijing 100871 

出　　处：《Journal of Earth Science》1998年第2期32-36,共5页地球科学学刊（英文版）

摘　　要：The fracturing of the pressure compartments in sedimentary basins may not be caused completely by natural hydraulic fracturing. On the bases of fracture mechanics and numerical simulation, we consider that there are two mechanisms concerning the fracturing of pressure compartments, which are as follows: (1) natural hydraulic fracturing of the sediments within pressure compartments, and (2) tensile fracturing due to tangential traction. When the fracture, formed in the sediments within pressure compartments due to hydraulic fracturing, arrives at the base of the seal, the intensely tangential tensile stresses are created and lead to the fracturing of the seal. After the seal fractured, the fluid escaped from the pressure compartments. In a shallow pressure compartment, the duration of fracture opening and fluid expulsion is about 10-20 years in a cycle.The fracturing of the pressure compartments in sedimentary basins may not be caused completely by natural hydraulic fracturing. On the bases of fracture mechanics and numerical simulation, we consider that there are two mechanisms concerning the fracturing of pressure compartments, which are as follows: (1) natural hydraulic fracturing of the sediments within pressure compartments, and (2) tensile fracturing due to tangential traction. When the fracture, formed in the sediments within pressure compartments due to hydraulic fracturing, arrives at the base of the seal, the intensely tangential tensile stresses are created and lead to the fracturing of the seal. After the seal fractured, the fluid escaped from the pressure compartments. In a shallow pressure compartment, the duration of fracture opening and fluid expulsion is about 10-20 years in a cycle.

关 键 词：pressure compartments FRACTURING episodic fluid expulsion. 

分 类 号：P55[天文地球—构造地质学]