DETERMINING THE CRUSTAL STRESS FIELD USING ANSYS CURVED SHELL MODEL

Zhongyuan Oilfield belongs to complex block Oilfield, which features multiple fault blocks and high formation dip angle. The abnormal crustal stress causes casing shrinking deformations or breaks frequently, and this in turn shortens the well life. A qualitative and quantitative study is conducted, aiming at resolving the problem of casing damage from the root. Using the Curved Shell Model of the Finite Element Method, the stress field of the active structures in the formation is simulated, and the maximum and minimum horizontal main stress maps are drawn accordingly. It is concluded that the area with relatively large difference between the maximum horizontal main stress and minimum horizontal main stress, and the boundary areas with dramatic stress changes are subject to casing damage easily. This method can be used to simulate the real geological conditions quickly and accurately, and it has been widely used for the prevention and treatment of casing damage.