摘要
根据砂岩薄片、铸体薄片、扫描电镜、高压压汞、黏土矿物X衍射、常规物性等分析测试资料,研究了鄂尔多斯盆地志丹油田西北部长6—长9致密砂岩储层的微观特征。结果表明:长6—长9砂岩储层岩石类型主要为细粒长石砂岩,胶结物成分主要为方解石;储层物性总体很差,属于致密储层,但不同层位储层物性差异明显;储层孔隙类型以长石类溶孔为主,其次为残余粒间孔,孔隙结构极其复杂;成岩作用类型包括压实作用、胶结作用和溶蚀作用;影响储层物性的因素主要与沉积相和成岩作用有关,不同沉积微相和粒度变化的储层物性差异明显,其中水下分流河道微相储层物性最好;压实作用是破坏储层物性的第一要素,胶结作用使储层进一步致密化,而溶蚀作用大大改善了储层物性;构造成因的裂缝对储层渗透率有显著影响,而对孔隙度影响微弱。研究成果可为志丹油田致密油藏的勘探与开发提供一定的借鉴。
The microscopic characteristics of Chang 6-Chang 9 tight sandstone reservoir in the northwest of Zhidan Oilfield,Ordos Basin were studied based on the analysis data of sandstone slice,cast thin section,scanning electron microscope,high-pressure mercury injection,clay mineral X diffraction and conventional physical property.The results show that the rock type of the Chang 6-Chang 9 sandstone reservoir is mainly fine-grained feldspar sandstone,its cementation is mainly calcite;the physical property of the reservoir is very poor,which belongs to tight reservoir,but the physical property of different horizons is obviously different;the pore types of the reservoir are mainly feldspar dissolved pores,followed by residual intergranular pores,and pore structure is extremely complex;diagenesis includes compaction,cementation and dissolution;the influence factors of reservoir physical property are mainly related to sedimentary facies and diagenesis,the physical property of the reservoirs of different sedimentary microfacies and grain size change is obviously different,among which the reservoir of underwater distributary channel microfacies has the best physical property;compaction is the first factor to destroy reservoir physical property,cementation makes reservoir more compact,while dissolution greatly improves reservoir physical property;structural fractures have a significant effect on reservoir permeability,but have little effect on porosity.The research results can provide some references for the exploration and development of tight reservoirs in Zhidan oilfield.
作者
孙昆
白玉彬
陈莹
庞长旭
贺姣姣
SUN Kun;BAI Yubin;CHEN Ying;PANG Changxu;HE Jiaojiao(Zhidan Oil Production Plant,Yanchang Oilfield Limited Corporation,Yan'an 717500,Shaanxi,China;College of Earth Sciences and Engineering,Xi'an Shiyou University,Xi'an 710065,Shaanxi,China)
出处
《西安石油大学学报（自然科学版）》
CAS
北大核心
2018年第5期34-41,共8页
Journal of Xi’an Shiyou University（Natural Science Edition）
基金
陕西省自然科学基础研究计划资助项目(2017JM4014)
陕西省教育厅重点科研项目(18JS145)
关键词
致密砂岩
储层微观特征
延长组
志丹油田
鄂尔多斯盆地
tight sandstone
microcosmic characteristics of reservoir
Yanchang Formation
Zhidan Oilfield
Ordos Basin
