川东北黄龙场构造飞仙关组四段底部裂缝预测研究

Fracture prediction of the bottom of T_1f^4 in Huanglongchang structure,northeastern Sichuan Basin

根据川东北构造的区域演化历史分析,黄龙场构造是多期构造运动相互叠加、相互影响的结果,对其形成影响最大的是晚喜山运动北东—南西向作用力。该文采用有限元数值模拟方法,并结合Mohr-Coulomb准则对黄龙场构造飞仙关组四段底部裂缝进行了预测,裂缝主要分布在靠近黄龙场构造高点附近、断裂两侧和断裂交汇处。在2期构造应力场作用下,黄龙场构造形成了2期共6组裂缝,裂缝延伸方向主要为北西向、北东向、近东西向和近南北向。

According to the regional tectonic evolution in northeastern Sichuan Basin,Huanglongchang structure is the result of multiphase tectonic movements,and it is mostly affected by the force from NE to SW during the late Himalayan movement.The finite element method and Mohr-Coulomb criterion are used to predict the fractures at the bottom of T1 f 4 in Huanglongchang structure.The result shows that the fractures are well developed in structural high and nearby,two sides of fault,as well as the intersections of faults.Underwent two periods of tectonic stress,six groups of fractures are formed in Huanglongchang structure,and the main trends of these fractures are NW,NE,NNE and NNW.