东濮凹陷文南沙三中亚段致密性储层裂缝发育特征及主控因素研究

基于对构造作用的研究,利用测井、地震、岩石物性、沉积相资料分析,揭示文南低品位区块沙三中亚段致密性砂岩储层裂缝发育特征.工区主要发育的裂缝类型有高角度构造裂缝、低角度卸载裂缝两类,裂缝主要走向为北东向,倾角为45°～90°、0～30°,裂缝充填程度低,优势方位的裂缝走向与现今最大水平主应力方向大致一致,裂缝连通性较好.裂缝分布区域与构造作用、构造部位以及岩性有密切关系,断层附近富含砂岩的水下分流河道微相裂缝最为发育.两类裂缝的成因都与工区目的层段下伏盐底辟有关,由于底辟作用造成的地层上隆不仅使上覆地层产生高角度的拉张裂缝,而且导致地层上覆载荷卸载产生低角度的卸载裂缝.综合研究表明,两类裂缝在空间上的搭配组成了良好的裂缝网络系统,对剩余油气的开采具有重要意义.

Reservoir Fractures and Main Controlling Factors in Mid-sha-3 Member, Shahejie Formation in Wennan, Dongpu Depression

By using logging, seismic, petrophysical properties and sedimentary facies data analysis, study based on tectonism, development characteristics development characteristics of tight sandstone reservoir fractures in mid-sha-3 member, shahejie formation, low grade block in wennan was studied low grade block tight sandstone reservoir fracture of mid-sha-3 member, Shahejie formation in Wennan were studied. The results show that: Two types of fracturesSare mainly developedSin work area:Shigh angleSfractures and low angleSunloading fractures; Most major fractures were developed towards the North East, and had an inclination of 45 ~ 90 °, 0 ~ 30 °; Fracture fillingSdegree was low, and the trend of dominant orientation of fractures was consistent with the current maximum horizontal principal stress direction, comprising the good porosity and permeability of the fracture network system. Regions fracture distributed were closely related to tectonic action, tectonic position and lithology. Cracks in Rich in sandstone of underwater distributary channel microfacies near fault are the most development. Causes of two types ofSfractureSSwere related with theSSsalt diapir underlying the objective layer, and strata uplifting caused by diapirism not only made the overlying strata have high angle tension fractures, but also caused the overlying strata load to unload, producing low angle fracture. Comprehensive studies indicate that, the collocation of two types of fractures in time and space constituted the good fracture network system, and significantly exploit the remaining oil and gas.