东营凹陷东辛断裂带联合应力机制构造物理模拟

Structural physical simulation of combined stress mechanism of Dongxin fault zone in Dongying Depression

王瑾 冯建伟 蒋榕韬 张鹏飞 任启强

中国石油大学（华东）地球科学与技术学院，山东 青岛 266580 中国石化胜利油田分公司勘探开发研究院，山东 东营 257000

School of Geosciences, China University of Petroleum, Qingdao 266580, China Exploration and Development Research Institute, Shengli Oilfield Company, SINOPEC, Dongying 257000, China

文中采用构造物理模拟手段对东营凹陷中央隆起带东段东辛断裂带的成因机制进行实验研究。选用石英砂、黏土及水的混合物为实验材料模拟孔店组与沙河街组地层，以研究区构造图为基础，等比例缩小，设定物理模拟边界，通过控制混合物下方的塑料膜以及向塑性层中的真空袋内注入硅胶的方式来研究力的方向、大小和底辟上拱等因素对于构造形成的影响。模拟结果表明：断裂带是在长期近SN向拉张力与右旋走滑背景下形成的；东部辛镇构造Xin120与Xin1断层之间的EW向三、四级断层是塑性层滑脱与张扭应力共同作用下的结果；西部由于塑性层上拱形成了东营穹窿，一定程度上影响了Ying1断层的发育形态，后期在张扭应力环境下形成了Ying31与Ying1的断层调节带。

The formation mechanism of Dongxin fault zone in the eastern part of the central uplift of Dongying depression were studied by means of physical simulation. The experimental material, mixed of quartz sand, clay and water, was used to simulate the stratum of Kongdian Formation and Shahejie Formation. Based on the structural map of the study area, the scale is reduced equally and the boundary of physical simulation is set. By controlling the plastic film under the mixture and injecting silica gel into the vacuum bag in the plastic layer, the influence of the direction, magnitude of the force and the diapir arching on the formation of the structure is studied. The simulation results show that the fault zone is formed under the background of long-term near SN tension and right lateral strike slip. The third and fourth order EW faults between the xin120 and Xin1 in the eastern Xinzhen structure are the result of the joint action of plastic layer detachment and tensile torsion. The Dongying dome was formed in the arching of the plastic layer in the west, which affected the development of Ying1 fault to a certain extent. In the later stage, the fault regulating zones of Ying31 and Ying1 were formed under the tension and torsion stress environment.

10.6056/dkyqt202101014