摘要
为推进鄂尔多斯盆地正宁地区致密油气的勘探开发,基于长8油层组岩心薄片、扫描电镜及压汞资料,分析了储层发育特征、储层致密化的原因及物性与含油性的关系。结果表明,长8油层组岩性以岩屑长石砂岩和长石岩屑砂岩为主,填隙物含量较高,碎屑颗粒结构成熟度低。储层孔隙包括基质孔隙和裂缝两大类,基质孔隙主要发育粒间孔和长石溶孔,裂缝主要发育构造裂缝和成岩微裂缝。基质孔隙以小孔、细喉为主。压实作用和胶结作用均是储层致密的主要原因,天然裂缝是油气重要的渗流通道,溶蚀作用和天然裂缝均改善了储层物性。物性分布与砂体分布具有较好的一致性,长81小层物性明显优于长82小层。良好的物性是油井高产的关键因素。
In order to promote the exploration and development of tight oil and gas in Zhengning area,Ordos Basin,based on core slice,scanning electron microscope and mercury injection data,reservoir characteristics,reservoir densification and relationship between physical properties and oil-bearing property were analyzed. The Chang8 sandstone is mainly composed of feldspar lithic sandstone and lithic feldspar sandstone,with high content of interstitial matter,which is mainly composed by ferroan calcite,hydromica,chlorite membrane,kiesel,and kaolinite. The Chang 8 sandstone is low in clastic structure maturity,which is mainly medium-sorted subangular particles. Matrix pores and natural fractures jointly form reservoir pore system,and matrix pores are mainly small pores with fine throat. Compaction and cementation are main densification origins for Chang 8 tight reservoir.Natural fractures are main percolation pathway,and together with dissolution,they improved reservoir physical properties. Physical properties of Chang 81 reservoir are obviously better than that of Chang 82 reservoir. Oil-bearing is relative with physical property. Better physical property is the key for high oil production.
出处
《岩性油气藏》
CSCD
北大核心
2017年第6期32-42,共11页
Lithologic Reservoirs
基金
国家自然科学基金"泥质岩层对低渗透砂岩储层油气成藏的控制机理研究"(编号:41502146)
国家重点基础研究发展(973计划)项目"致密油(页岩油)赋存与运聚机理"(编号:2014CB239005)
中国石油科技创新基金项目"源储间的薄层泥岩对致密砂岩储层含油性的控制机理研究"(编号:2015D-5006-0101)联合资助
关键词
致密油
长8油层组
储层特征
正宁地区
鄂尔多斯盆地
tight oil
Chang 8 reservoir
reservoir characteristics
Zhengning area
Ordos Basin