塔里木盆地压扭构造组合与油气聚集

Compressive-torsional structure system and hydrocarbon accumulation in the Tarim basin

自加里东运动后期开始，塔里木盆地先后受到了北部大洋板块和古特提斯洋权决的近南北向的俯冲挤压作用，产生了北西、北东向的剪切应力场，在这种应力作用下，发育了一系列压扭构造。这些压扭构造由主压扭断裂及其派生的次级断裂和褶皱组成，形成一定规律的压扭构造组合，即派生的次级断裂和褶皱斜交或呈雁行排列于主断裂一侧。这些压扭构造形成早，继承性强，后期构造运动对其改造作用较弱，对油气聚集和保存权为有利，现已发现的大部分古生界油气藏及部分中生界构造油气藏均分布于压扭构造组合内的圈闭中。可见，压扭构造组合是塔里木盆地油气勘探的重要领域。

After mid Caledonian movement, the Tarim basin was compressed in northsouth direction by both the downthrusting north-Oceanic plate and the Tethys Sea plate, so that the northwest and northeast shear stresses appeared, which caused a series of compressive-torsional structures in this basin. These compressive-torsional structures are respectively formed by major compressive-torsional fault, derivative fault and fold; and they occur in some regular compressive-torsional structure systems; to speak in detail, the derivative secondary faults and folds are oblique with the major fault, forming echelon pattern along one side of the major fault.The compressive-torsional structures are characterized by early generation, very obvious heritable characteristics, weak change due to later structural movement,and favourable condition for hydrocarbon accumulation and reservation. Most discovered Palaeozoic reservoirs and some discovered Mesozoic structural reservoirs exist in the traps of the compressive-torsional structure systems. lt may be seen from these that compressive-torsional structure system in the Tarim basin is important area of hydrocarbon exploration.