辽河油田东部凹陷奥陶系碳酸盐岩储层特征分析及评价

Study and evaluation of carbonate reservoir characteristics of Ordovician system in eastern sag of Liaohe Oilfield

以岩石薄片、扫描电镜、物性、毛管压力曲线等资料及测井解释结果为依据,从物性特征、岩性特征、孔隙类型及孔隙结构等方面对东部凹陷下古生界奥陶系储层进行了综合评价,认为奥陶系碳酸盐岩储层整体上属于低孔低渗储层,孔隙度与渗透率关系不明显,显示一种受裂缝影响的储层。与华北地台其他地区物性进行了对比,可对比性较强,具备形成工业油气流的储集条件。综合储层的岩性、物性和孔隙结构等特征,参考渤海湾盆地储集层分类标准,对东部凹陷奥陶系储层进行了分类,区内下古生界主要发育Ⅰ类储层,少量Ⅱ类储层。其中奥陶系马家沟组、冶里组储集条件较好,为有利储层发育区。

Based on the rock section, SEM, physical property, lithologic features, capillary pressure curve and results of well log interpretation, Ordovician reservoirs in eastern sag were comprehensively evaluated from the physical property, pore type and pore structure. It is considered that the lower Paleozoic reservoir is a middle - high porosity and middle - high permeability one. There is no clear relationship between porosity and permeability, but the reservoir is influened by fracture. Moreover compared with North China platform, it is shown that the reservoir has industrial oil and gas flow conditions. Based on the above analyses and referred to reservoir evaluation criterion of Bohai Sea Bay,the Ordovician reservoirs were classified. In the area, most of the lower Paleozoic reservoirs are type Ⅰ, the next is type Ⅱ , in which the lower Paleozoic Mjg formation and Y1 formation are high quality reservoirs.