伊通地堑断层系统与构造样式

与走滑相关的盆地构造一般比较复杂,主要表现为断层系统较复杂和构造样式类型丰富。通过对三维地震资料进行系统的构造解析,结合区域地质和钻井资料的分析表明,伊通地堑的断层系统在平面上主要由近东西向的张性正断层和北东走向的张剪性断层组成,反映盆地具右旋走滑的应力体制;断层在演化序列上分为4个类型,与盆地的形成和演化之间存在良好的对应关系。地堑构造样式以"基底卷入型"为主,从盆地的动力学机制的角度,它属于"走滑—拉分型",进一步可将它概括为5种类型的构造样式,而且每一个断陷都以一种构造样式占主体,其展布具有明显的规律性。构造样式的差异是造成不同断陷具有独特油气分布规律的主导因素。

FAULT SYSTEM AND TECTONIC STYLE OF THE YITONG GRABEN

Strike-slip basins are commonly complex, mainly because of its complicated fault system and tectonic style. Based on systematic structural interpretation with 3D seismic data and analysis on regional geology and drilling data, the fault system and tectonic style of the Yitong Graben are studied. It is shown that the fault system of the Yitong Graben is mainly composed of EW strike extensional normal faults and NE strike wrench faults, and reflects a right lateral strike-slip stress field. There are four evolution types of faults, and well matched with the basin formation and evolution. The main tectonic style of the graben is the "basement involved", and is strike-slip and pull-apart origins, and can be subdivided into 5 types. There is only one dominant tectonic type in each fault depression. The difference of the tectonic styles is the main reason which causes each fault depression to have its own oil distribution law.