渤海郯庐断裂西支构造特征及对潜山形成的控制作用

渤海郯庐断裂西支是指郯庐断裂渤海段西侧分支断层，其形成演化对前新生代地层展布和潜山构造发育具有重要控制作用。基于三维地震、钻井、分析化验等资料，对渤海郯庐断裂西支构造特征、成因演化模式，以及对潜山形成的控制作用进行了分析。研究表明:①渤海郯庐断裂西支具有印支期、燕山早期、燕山中期、喜山早期多期叠加活动的特征，喜山晚期活化作用弱，整体隐伏于新生代沉积物之下；②渤海郯庐断裂西支具有显著的分段性，被近东西向断裂分割成北、中、南3段，各段在关键地质时期构造变形型式和强度存在一定差异；③印支期不均一南北向挤压所导致的走滑转换是渤海郯庐断裂西支的启动机制；④渤海郯庐断裂西支在印支期-燕山早期走滑逆冲活动及伴生褶皱是控制潜山地层展布及渤中19-6等潜山构造形成的关键因素。研究成果可以为渤海海域的油气勘探提供基础。 

Structural characteristics of the Western Branch of the Tanlu fault in Bohai Sea and its control on the formation of buried hills

The Western Branch of the Tanlu fault in Bohai Sea refers to the Western Branch fault of Bohai segment of the Tanlu fault, the formation and evolution of which plays an important role in controlling the distribution of pre Cenozoic strata and the development of the structure of buried hills.Based on the data of 3D seismic, drilling and experimental data, the structural characteristics, genetic evolution model of the Western Branch of the Tanlu fault in Bohai Sea and its control on the formation of buried hills are analyzed.The results show that: ①the Western Branch of Tanlu fault in Bohai Sea is characterized by multi-stage superimposed activities in Indosinian, Yanshanian and Himalayan.The activation of late Himalayan is weak, and it is concealed under Cenozoic sediments.②The Western Branch of the Tanlu fault in Bohai Sea is divided into three segments: north, middle and south by nearly EW trending fault.There are some differences in the structural deformation patterns and strength of each segment in the key geological period.③The Western Branch of the Tanlu fault in Bohai Sea was originated from strike slip transition caused by uneven N-S compression in Indosinian.④Indosinian-Yanshanian strike slip thrust and associated folds in the Western Branch of the Tanlu fault in Bohai Sea are the key factors controlling the distribution of strata buried hills and the formation 19-6 buried hill structures of Bozhong.The research results can provide a basis for oil and gas exploration in Bohai Sea.