驾掌寺地区沙河街组碎屑岩储层特征及影响因素分析

Clastic reservoir characteristics and influence factor analysis of Shanghejie formation,Jiazhangsi area

通过岩心观察、薄片鉴定、物性分析和扫描电镜观察等技术手段,研究了驾掌寺地区沙河街组碎屑岩储层的岩石学特征、成岩作用、孔隙结构、储层物性及影响因素。研究结果表明,储层以粒间孔和溶蚀孔最为发育,为中孔中渗和低孔中低渗储层。储层物性受成岩作用和沉积微相双重因素影响,垂向上压实和胶结作用使储层物性明显变差,而溶蚀作用产生次生孔隙使储层物性得到改善;平面上储层物性受沉积相带控制。综合分析认为沙一段水下分流河道和河口砂坝、沙三段河道微相是油气聚集的有利相带,也是滚动勘探、开发调整的方向。

With core observation,thin section analysis,physical property analysis and scanning electronmicroscope observation, litholo gy characteristics, diagenesis, pore structure, physical properties and influence factors of clastic reservoir of Shahejie formation in Jiazhangsi area were studied. The result indicates that the reservoir was middle porosity ?middle permeability and low porosity - middle - low permeability one with granular and dissolution pores developed well. Reservoir physical properties were affected by diagenesis and sedimentary microfacies. Vertical compaction and cementation made these physical properties obviously poor,and secondary pores caused by dissolution improved these physical properties. The reservoir physical properties at plane were controlled by sedimentary facies belt. Comprehensive analysis showed that the subaqueous distributary channel and river mouth bar in Shal member and chan-nelmicrofacies in Sha3 member were the favorable facies belt of hydrocarbon accumulation and the targets of roll exploration and development adjustment.