To supply scientific and valid foundation of exploitation, we study the physical property and influence elements of Chang 6 Bed of Yanchang Formation in Baliangou-Jinzhuang area of Nanniwan Oil Field. A synthesis analysis by using the casting lamella, scanning electron microscope, porosity and permeability analysis, the log interpretation and mercury injection test was carried out. The results show that the lithologic characteristics of reservoir mainly include silty-midium arkose. The pore space of the reservoir mainly includes the dissolution and residual intergranular pores. Pore structures are mostly the type of middle class of discharge pressure and throat and the type of high class of discharge pressure and thin throat, with strong variability, complexity and heterogeneity. General property belongs to low hole extra-low permeability reservoirs. The characteristics of the reservoir are affected by deposition and diagenesis, and underwater distributary channel is the main favorable microfacie. The physical property was declined mainly for the cementation and compaction and pressolution processes. The dissolution is intense, whose dissolution pore is the important pore space for Chang 6 sandstone reservoir in the study region. The microfracture developed here has constructive effect on improving the petrophysical property of the reservoir and connectivity of pore throat.%通过岩性数据、铸体薄片、扫描电镜、压汞曲线及物性等资料的统计分析,对鄂尔多斯盆地八连沟-金庄地区长6储层的岩石学特征、孔隙结构和物性特征进行了研究.结果表明,该区块长6油层组总体物性属于低孔、特低渗储层,孔隙类型主要包括溶蚀粒间孔、残余粒间孔、溶蚀粒内孔、溶蚀填隙物内孔和溶蚀微裂缝5种类型.该区孔隙结构以中排驱压力-中喉道型及高排驱压力-细喉道型为主,具有较强的多变性、复杂性及非均质性.储层物性受沉积作用和成岩作用的综合影响,水下分流河道是形成有利储层的主要相带,胶结作用和压实压溶作用是导致储层物性变差的最主要原因,溶蚀作用产生的溶蚀孔隙是重要的储集空间,裂缝的存在大大改善了储层的物性条件.
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