摘要
针对鄂尔多斯盆地蟠龙油田长2油藏规模小但储量高、孔隙度相对较高但渗透率低、隐蔽性强且勘探难度大的特点,通过岩心观察、薄片鉴定、粒度分析、扫描电镜分析、压汞测试及全岩X衍射分析等多种方法对长2储层岩石学特征、孔隙类型、孔喉结构以及物性特征等进行研究,并从沉积相、成岩作用以及岩石成分等多角度对低渗透储层的控制因素进行深入分析。研究结果表明,蟠龙油田长2油层组低渗透砂岩为辫状河流沉积,储渗体系由长石砂岩和岩屑长石砂岩中的残余粒间孔、溶蚀孔和微裂缝等组成。共发育4类孔隙结构且河道砂体物性最好。压实作用造成孔隙度损失最大,胶结作用次之,溶蚀作用改善了储层物性。石英、长石等组分含量与孔隙度、渗透率呈正相关,岩屑、黑云母与杂基、碳酸盐矿物和钙质等组分含量与储层物性呈负相关关系,微裂缝对储层渗透率贡献明显(尤其是渗透率大于10×10^(-3)μm^(2)时)。
Chang 2 reservoir in Panlong Oilfield of Ordos Basin is characterized by small scale but high reserves,relatively high porosity but low permeability,strong concealment and great difficulty in exploration.Therefore,the petrological characteristics,pore types,pore throat structure and physical properties of the Chang 2 reservoir are studied by means of core observation,thin section identification,particle size analysis,scanning electron microscope analysis,mercury intrusion test and whole rock X-ray diffraction analysis,and the controlling factors of low permeability reservoir are analyzed in depth from the perspectives of sedimentary facies,diagenesis and rock composition.The results show that the low permeability sandstone of Chang 2 oil-bearing formation in Panlong Oilfield is a braided river deposit,and the storage and seepage system is composed of residual intergranular pores,dissolution pores and microfractures in arkose and lithic arkose.The pore structure of the study area can be divided into four types,and the physical property of river channel sandstone is the best.Compaction causes the greatest loss of porosity,followed by cementation,and dissolution improves the physical properties of the reservoir.The porosity and permeability of the reservoir are positively correlated with content of quartz and feldspar,but negatively correlated with rock debris,blackmica and miscellaneous groups,carbonate minerals and calcium,and the microcracks contribute significantly to the permeability(especially when the permeability is greater than 10×10^(-3)μm^(2)).
作者
董海波
相金元
李玲
白聪萍
何子琼
王美霞
郭艳琴
DONG Haibo;XIANG Jinyuan;LI Ling;BAI Congping;HE Ziqiong;WANG Meixia;GUO Yanqin(Development Department,Yanchang Oilfield Co.,Ltd.,Yan’an,Shaanxi 716000,China;Department of Engineering Technology,CNPC Western Drilling Engineering Co.,Ltd.,Urumqi,Xinjiang 830011,China;No.7 Oil Production Plant,PetroChina Changqing Oilfield Company,Xi’an,Shaanxi 710018,China;Nanniwan Oil Production Plant,Yanchang Oilfield Co.,Ltd.,Yan’an,Shaanxi 716000,China;School of Architecture,Chengdu Jincheng College,Chengdu,Sichuan 611731,China;PetroChina Coalbed Methane Company Limited,Beijing 100020,China;College of Earth Sciences and Engineering/Shaanxi Key Laboratory of Petroleum Accumulation Geology,Xi’an Shiyou University,Xi’an,Shaanxi 710065,China)
出处
《西安石油大学学报（自然科学版）》
CAS
北大核心
2022年第5期29-35,46,共8页
Journal of Xi’an Shiyou University（Natural Science Edition）
基金
国家科技重大专项专题(2017ZX05005002-004)
国家油气重大专项项目(2016ZX05046-002)
国家自然科学基金重大项目(41390451,41330315)
国家自然科学基金青年项目(41502107)
地质矿产调查评价基金资助项目(121201011000150014)
陕西省自然科学基础研究计划资助项目(2017JQ4018)。
关键词
储层物性
孔隙结构
成岩作用
长2油层组
鄂尔多斯盆地
reservoir physical property
pore structure
diagenesis
Chang 2 reservoir
Ordos Basin
