深层致密砂岩储层非均质性特征及控制因素——以准噶尔盆地永进地区侏罗系齐古组为例

Heterogeneity characteristics of deep tight sandstone reservoir and its controlling factors:a case study of Jurassic Qigu Formation in Yongjin Area,Junggar Basin

以准噶尔盆地永进地区侏罗系齐古组为例,根据岩心、薄片、储层物性和测井数据等资料,分析深层致密砂岩储层非均质性特征并进行综合表征,明确储层非均质性控制因素。结果表明:研究区齐古组自下而上分为1~6小层,粒度韵律和渗透率韵律以正韵律为主,在层内非均质性方面,3小层的非均质性最强;在层间非均质性方面,1~3小层砂体展布面积大且连通性好,3小层砂体最发育;在平面非均质性方面,1~4小层具有较强非均质性。3小层的非均质性最强,其次分别为2小层、4小层和1小层的。沉积作用影响砂体展布及物质组成,是导致储层非均质性的基础,成岩作用能够改善孔隙结构和类型,是影响储层非均质性的关键因素。该结果对准噶尔盆地永进地区油气勘探具有指导意义。

Taking the Jurassic Qigu Formation in Yongjin Area of Junggar Basin as an example,based on the data of core,thin section,reservoir physical properties and logging data,the quantitative study of heterogeneity parameters was carried out to analyze the heterogeneity characteristics of deep tight sandstone reservoirs and clarify the controlling factors of reservoir heterogeneity.The results show that the Qigu Formation in the study area is divided into 16 sub-layers from bottom to top.The grain size rhythm and permeability rhythm are mainly positive rhythm.In terms of intra-layer heterogeneity,the heterogeneity of the three sub-layers is the strongest.In terms of interlayer heterogeneity,the sand bodies of 13 layers have a large distribution area and good connectivity,and the sand bodies of 3 layers are the most developed.In terms of plane heterogeneity,14 layers have strong heterogeneity.The heterogeneity of small layer 3 is the strongest,followed by small layer 2,small layer 4 and small layer 1.Sedimentation affects sand body distribution and material composition,which is the basis of reservoir heterogeneity.Diagenesis can improve pore structure and type,which is the key factor affecting reservoir heterogeneity.The results have guiding significance for oil and gas exploration in Yongjin Area of Junggar Basin.