新立油田低渗透储层微观孔隙结构特征及分类评价

Microscopic characteristics of pore structure and classification evaluation of low permeabilityreservoir in Xinli Oilfield

以新立油田扶杨油层为例,开展了低渗透储层微观孔隙结构特征的研究。在取心井铸体薄片、扫描电镜和压汞测试等分析化验的基础上,通过分析储层的孔隙类型和孔隙结构,将储层微观孔隙结构分为4类,阐述了各类微观孔隙结构的特征。沉积作用和成岩作用的双重影响使得扶杨油层的储层孔隙结构异常复杂,粒间溶孔、粒内溶孔、铸模孔和晶间晶内微孔等次生孔隙构成了该区的主要储集空间。孔隙喉道组合类型以小孔细喉型组合为主,中孔中喉型和中孔小喉型组合次之,少部分为微孔微细喉组合。选用孔隙度、渗透率、排驱压力、最大孔喉半径、平均孔喉半径和分选系数等参数,采用聚类分析和判别分析的方法,通过建立判别函数,对新立油田扶杨油层进行了微观孔隙结构识别,并勾绘出主力小层的综合评价图,进一步分析表明,Ⅰ类和Ⅱ类储层为研究区的优质储层,是今后低渗透扶杨油层勘探开发的主要目标。

Taking the Fuyang reservoir in Xinli Oilfield as an example,the microscopic pore structures of low permeability reservoir was researched.Based on the analysis on reservoir pore types and structures and the information offered by casting slice,scanning electron microscope and mercury injection test of core wells,the microscopic pore structure was classified into four types,and the characteristics of each microscopic pore structure type were de-scribed in detail.Sedimentation and diagenesis were the major con...