摘要
英西深层碳酸盐岩油气藏是近年来柴达木盆地油气勘探最重要的成果,多口日产超千吨(油当量)井的发现揭示了区内巨大的资源潜力,同时该区复杂的地质条件也给勘探工作带来了巨大的挑战。为了进一步认识英西深层油气藏地质特征及成藏主控因素,对近年来研究工作取得的新认识进行系统总结和梳理,认为:(1)英西E_(2-3)xg^2烃源岩厚度大(可达2 000m)、TOC含量高(0.6%~2.2%)、有机质类型(Ⅱ_1干酪根)及成熟度(R_O=0.7%~1.5%)适合,为区内大规模生烃奠定了基础;(2)受喜马拉雅运动控制,英西软硬岩层间互发育的地层在挤压应力背景下形成了独特的"双层结构"构造样式;(3)英西E(2-3)xg^2储层岩性为混积碳酸盐岩,孔—缝复合型储集空间是高效储层形成的必要条件,晶间孔广泛发育是区内整体含油的基础;(4)英西深层油气藏经历了早、中、晚3个成藏期,以中期为主;盐岩盖层的存在不仅导致英西深层普遍存在异常高压,还导致盐间、盐下油气藏成藏模式存在较大差异。
The discovery of deep carbonate hydrocarbon-bearing pool in the western Yingxiongling area is the most important achievement for oil-gas exploration in Qaidam Basin during the past a few years.Several wells with over 1 000 tons of oil equivalent daily output revealed a huge resource capacity in this region. Meanwhile,the complex geological conditions of this region brought a huge challenge for the exploration work.In order to further understand the geological characteristics and controlling factors of the deep hydro- carbon-bearing pool in the western Yingxiongling area,the new research findings that achieved during the past years were organized and summarized.Their conclusions indicated （1）the E2-3xg2 source rocks in the western Yingxiongling area are characterized by thick thickness （reached 2 000m）, high TOC content （0.6%-2.2 %） ,suitable kerogen type （ II 1 ）and maturation （Ro =0.7%-1.5 %） ,these conditions provided a foundation for huge hydrocarbon generation; （2）controlled by the Himalayan tectonic movements, the strata in the western Yingxiongling area constituted by interbedded soft and hard rock layers deformed in a compressive stress background, formed special structural style of ＂double-layer structure＂; （3）the lithology of the E2-3xg^2 reservoir is mixed carbonate rock,pore-fracture coupled reservoir space created the necessary condition for high effective reservoirs,wide developed inter crystalline pore was the foundation for regional hydrocarbon-bearing; （4）deep hydrocarbon-bearing pool in the western Yingxiongling area experienced three accumulation episodes included early episode, middle episode and late episode, the middle episode was the main accumulation episode in the study area. The existence of halite seal layers not only led to wide spread of abnormal pressure in the deep hydrocarbon-bearing pool in the western Yingxiongling area, but also led to the differences of accumulation models between the hydrocarbon deposits occurring inter- and below-halite beds
作者
张永庶
伍坤宇
姜营海
王鹏
蔡智洪
高发润
谭武林
高树芳
鲜本忠
Zhang Yong-shu1 ,Wu Kun-yu1 ,Jiang Ying-hai1 ,Wang Peng1 ,Cai Zhi-hong1, Gao Fa-runI , Tan Wu-lin1, Gao Shu fang1 , Xian Ben-zhong2(1.Research Institute of Exploration ＆ Development of Qinghai Oilfield Company ,CNPC ,Dunhuang 736202 ,China ; 2.College of Geosciences ,China University of Petroleum ,Beijing 102249, China)
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2018年第3期358-369,共12页
Natural Gas Geoscience
基金
中国石油天然气股份有限公司重大科技专项(编号:2016E-0102)
国家自然科学基金(编号:41372117)
国家科技重大专项(编号:2017ZX05009-002)
青海油田科技项目(编号:研2017-内部-勘探-07)联合资助
关键词
碳酸盐岩
油气藏
构造
储层
英西
Carbonate rock
Hydrocarbon-bearing pool
Structure
Reservoir
Western Yingxiongling area
