砂岩储集层致密与成藏耦合关系_以鄂尔多斯盆地西峰_安塞地区延长组为例.docxVIP

砂岩储集层致密与成藏耦合关系——以鄂尔多斯盆地西峰—安塞地区延长组为例刘明洁 1，刘震 1，刘静静 1，朱文奇 2，黄艳辉 1，姚星 1（1. 中国石油大学（北京）油气资源与探测国家重点实验室；2. 中海油研究总院）基金项目：中国石油“十二五”油气重大专项“岩性地层油气藏成藏规律、关键技术及目标评价”（2011ZX05001）摘要：以鄂尔多斯盆地西峰地区长 8 段和安塞地区长 6 段为研究对象，通过镜下包裹体荧光鉴定、孔隙度演化模拟以及石油充注临界实验，确定西峰—安塞地区三叠系延长组砂岩储集层致密与成藏时间的先后顺序。镜下包裹体荧 光鉴定发现，延长组砂岩储集层普遍存在石英次生加大边夹沥青和烃类包裹体现象；孔隙度演化模拟表明，成藏期延长组砂岩储集层孔隙度大于 10%，未达到致密状态；石油充注临界条件实验发现当西峰地区长 8 段和安塞地区长6 段砂岩孔隙度小于 10%时，即使在加压条件下，石油仍不能充注进入砂岩。综合研究表明鄂尔多斯盆地西峰—安 塞地区延长组砂岩储集层先成藏后致密，为典型的“后成型”致密砂岩油藏。成藏期之后，压实作用和自生矿物胶结作用才使得延长组砂岩储集层致密化。图 8 参 37关键词：先成藏后致密；烃类包裹体；孔隙度演化；石油充注；延长组；鄂尔多斯盆地中图分类号：TE122文献标识码：ACoupling relationship between sandstone reservoir densification andhydrocarbon accumulation: A case from the Yanchang Formation of the Xifeng and Ansai areas, Ordos BasinLiu Mingjie1, Liu Zhen1, Liu Jingjing1, Zhu Wenqi2, Huang Yanhui1, Yao Xing1(1. State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China;2. CNOOC Research Institute, Beijing 100027, China)Abstract: The Chang 8 member of the Xifeng Area and the Chang 6 member of the Ansai Area are taken as examples to define the relationship between the sandstone densification and accumulation from fluid inclusion identification, simulation of sandstone porosity evolution, and analysis of oil charge critical experiment. The fluid inclusion fluorescence shows that there is quartz overgrowth containing the residual asphalt and hydrocarbon inclusions existing in the sandstone reservoir of Yanchang Formation. The simulation of porosity evolution shows that the sandstone reservoir was not tight sandstone during the key accumulation period for the porosity was greater than 10%. The oil charge critical experiment indicates that the oil cannot charge into the sandstone if the porosity is less than 10% in Xifeng and Ansai, even under pressurized conditions. The results demonstrate that the Yanchang Formation of Xifeng Area and Ansai Area in the Ordos Basin is a typical “postforming” tight sandstone hyd