库车盆地依南气田构造变形特征及动力学机制

Features and Dynamics for Structure Deformation of Yinan Gas Field in Kuqa Basin, Northwestern China

对库车盆地依南气田的构造变形特征及动力学机制进行了系统研究。依南气田所在的依深背斜为一具被动顶板的大型双重逆冲构造 ,其上覆依奇克里克背斜为一大型断层传播褶皱。它们具有分段和左行左列的雁列式展布特征。受印 藏碰撞远距离效应的影响 ,背斜构造自晚第三纪中新世康村组沉积期开始形成 ,主要的作用力来源于碰撞作用所传递过来的构造挤压应力 ,多期自北而南的冲断作用是气田构造形成的根本原因。挤压作用不仅形成了大规模的逆冲断层及大型的断层相关褶皱 ,而且还产生了左行走滑作用 ,使断层在发生向南逆冲运动的同时还发生左行走滑运动 ,从而使背斜构造在走向上发生转折 。

The characteristics and dynamic mechanism for structure deformation of the Yinan gas field of Kuqa basin in northwestern China are presented systematically. The Yishen anticline that the Yinan gas field located at is a vast duplex at great depths that was engendered by four reverse faults dipping to the north in turn, but the Yiqikilike anticline above is a fault propagation fold that was mainly engendered by Yiqikeleke fault, one reverse fault dipping to the north. The Yishen and Yiqikelike anticlines started to develop since the sedimentary period of Kangcun Formation of Miocene Epoch in Neogene under the influence of the impact between the India and Eurasia continents that happened since the end of Eocene. The processes of structure deformation happened at multi phases. The anticline and the faults that brought the anticline into forming are composed of 4～6 segments, they extend NEE as a whole, but EW in parts. The direction, which present sinister lateral strike slip and hold a left rank intersect at a sharp angle, indicate that the main force comes from the stress force of SN. The stress gave birth to the thrust faults and anticline, and the sinister lateral strike slip component derived from the stress forces bring them turning in the corner.