鄂尔多斯盆地子长地区上古生界山2段储层特征

The Characteristics of Reservoirs in Shan 2 Member of Upper Paleozoic in Zichang area of Ordos Basin

鄂尔多斯盆地子长地区上古生界山2段存在大量天然气,弄清其储层特征对勘探开发具有指导意义.利用岩心观察和薄片鉴定结果研究鄂尔多斯盆地子长地区上古生界山2段储层特征,研究结果表明:山2段储层岩性为石英砂岩、岩屑石英砂岩和岩屑砂岩;主要的孔隙类型为粒内溶孔和高岭石晶间孔;压实、溶蚀作用较为强烈,胶结物类型主要为自生黏土矿物、自生硅质和方解石;山2段储层属于致密砂岩储层,储层孔隙度、渗透率在中部和东北部较高,孔、渗在平面上大致呈正相关关系;储层主要分布在中部和东北部,呈北东-南西向,西北部和东南部砂体发育较少.

There are hydrocarbon reservoir shows in shan 2 member of upper paleozoic in zichang area of ordos basin. It has guiding significance for exploration and development to make clear the characteristics of the reservoir. By using of the core observation and the thin section identification results, the characteristics of reservoirs in shan 2 member of upper paleozoic in Zichang area of ordos basin are studied. The results show that the reservoir rocks in shun 2 member are quartz sandstone, lithic quartz sandstone and lithic sandstone. The main pore types are intragranular dissolved pores and kaolinite intergranular pores. Compaction and dissolution are very strong, and the types of cements are mainly authigenic clay minerals, authigenie siliceous and calcite. The reservoirs in shun 2 member belongs to the tight sandstone reservoir, the porosity and permeability of the reservoir are higher in the central and northeast, and the porosity and permeability are generally positive correlation. The reservoirs are mainly distributed in the central and northeastern parts, which is distributed from the direction of north-east （NE） to south-west （SW）, and the sand bodies in the northwest and southeast are less developed.