1、第 35 卷 第 2 期2023 年 3 月岩性油气藏LITHOLOGIC RESERVOIRSVol.35 No.2Mar.2023完颜泽等:柴达木盆地英雄岭地区古近系油气成藏过程及其演化特征收稿日期:2022-05-26;修回日期:2022-07-18;网络发表日期:2022-10-14基金项目:国家自然科学基金青年基金“富含有机质泥岩盖层生排烃后封闭性变化”(编号:42002180)、中国石油天然气股份有限公司直属院所基金“柴达木盆地新近系烃源岩生烃产生有机酸对湖相碳酸盐岩的改造作用”(编号:2020D-5008-05)及中国石油天然气股份有限公司重大科技项目“深层超深层地质结构与构造样
2、式研究”(编号:2021DJ0201)联合资助。第一作者:完颜泽(1997),中国石油勘探开发研究院在读硕士研究生,研究方向为国内外油气战略评价和油气田开发研究。地址:(100083)北京市海淀区学院路 20 号中国石油勘探开发研究院。Email:。通信作者:龙国徽(1986),男,硕士,高级工程师,主要从事油气勘探综合研究与科研管理工作。Email:。文章编号:1673-8926(2023)02-0094-09DOI:10.12108/yxyqc.20230209引用:完颜泽,龙国徽,杨巍,等.柴达木盆地英雄岭地区古近系油气成藏过程及其演化特征 J.岩性油气藏,2023,35(2):94-1
3、02.Cite:WANYAN Ze,LONG Guohui,YANG Wei,et al.Hydrocarbon accumulation and evolution characteristics of Paleogene inYingxiongling area,Qaidam Basin J.Lithologic Reservoirs,2023,35(2):94-102.柴达木盆地英雄岭地区古近系油气成藏过程及其演化特征完颜泽1,龙国徽2,3,杨巍4,柴京超3,马新民4,唐丽3,赵健3,李海鹏3(1.中国石油勘探开发研究院,北京 100083;2.中国地质大学(北京),北京 100083;
4、3.中国石油青海油田公司,甘肃 敦煌 736202;4.中国石油勘探开发研究院 西北分院,兰州 730020)摘要:通过构造演化特征研究,结合烃类包裹体分析和典型油气藏精细解剖,阐述了柴达木盆地英雄岭地区古近系下干柴沟组上段油气藏的形成和演化过程。研究结果表明:英雄岭地区古近系下干柴沟组上段形成于半咸化咸化湖泊盐湖环境,发育以纹层状灰云岩为储集层、富含有机质、广覆式分布的源储一体型油气藏;研究区下干柴沟组上段共经历 3 期油气充注,第期烃类包裹体为单一液相油包裹体,反映了早期低熟原油的运移和充注;第期烃类包裹体为单一液相油包裹体,反映了一幕中等成熟原油的运移和充注;第期烃类包裹体为气液两相油包
5、裹体,反映了一幕高成熟原油的充注。研究区油气具有 3 期成藏的特征:上干柴沟组沉积中晚期,在下干柴沟组上段形成了低饱和度-低熟油藏;上油砂山组沉积期,低熟成熟油气向盐间储集层和高渗带聚集形成了油气高产区;狮子沟组七个泉组沉积期,成熟高熟油通过双层断裂接力输导运移至干柴沟组上段及以上地层运聚形成构造油气藏。关键词:咸化湖泊;纹层状灰云岩;晶间孔;高渗带;页岩油;低熟烃源岩;下干柴沟组上段;古近系;英雄岭地区;柴达木盆地中图分类号:TE122.1;P618.13文献标志码:AHydrocarbon accumulation and evolution characteristics of Pale
6、ogene inYingxiongling area,Qaidam BasinWANYAN Ze1,LONG Guohui2,3,YANG Wei4,CHAI Jingchao3,MAXinmin4,TANG Li3,ZHAO Jian3,LI Haipeng3(1.PetroChina Research Institute of Petroleum Exploration&Development,Beijing 100083,China;2.China University of Geo-sciences(Beijing),Beijing 100083,China;3.PetroChina
7、Qinghai Oilfield Company,Dunhuang 736202,Dunhuang,China;4.PetroChina Research Institute of Petroleum Exploration and Development-Northwest(NWGI),Lanzhou 730020,China)Abstract:Through the study of structural evolution characteristics,combined with the analysis of hydrocarboninclusions and fine dissec
8、tion of typical oil and gas reservoirs,the formation and evolution process of oil and gas完颜泽等:柴达木盆地英雄岭地区古近系油气成藏过程及其演化特征2023 年95reservoirs in the upper member of Paleogene Xiaganchaigou Formation in Yingxiongling area of Qaidam Basinwere analyzed.The results show that:(1)The upper member of Xiagancha
9、igou Formation in Yingxiongling areaexperienced a semi saline lake,saline lake and salt lake environment during the Paleogene period,and formed alarge area of source-reservoir type oil and gas reservoir dominated by laminated calcite dolomite which is rich inorganic matters.(2)The upper member of Xi
10、aganchaigou Formation in the study area has experienced three stagesof oil and gas filling.The hydrocarbon inclusions in the first stage are single liquid oil inclusions,reflecting themigration and filling of early low mature crude oil.The hydrocarbon inclusions in the second stage are single liquid
11、oil inclusions,which reflects the migration and filling of medium mature crude oil.The hydrocarbon inclusionsin the third stage are gas-liquid two-phase oil inclusions,reflecting an episode of filling of highly mature crudeoil.(3)The oil and gas in the study area are characterized by three stages of
12、 accumulation.In the middle and latestages of the deposition of Shangganchaigou Formation,reservoirs with low saturation and low maturity formedin the upper member of Xiaganchaigou Formation.In the sedimentary period of Shangyoushashan Formation,low mature to mature oil and gas accumulated to the sa
13、lt reservoirs and high permeable zones,forming a high oiland gas production area.During the sedimentation period of Shizigou Formation to Qigequan Formation,mature-highly mature oil migrated to the upper member of Ganchaigou Formation and above through the transport ofdouble layer faults to form str
14、uctural oil and gas reservoirs.Key words:saline lake;laminated calcite dolomite;intercrystalline pore;high permeable zone;shale oil;lowmature source rock;upper member of Xiaganchaigou Formation;Paleogene;Yingxiongling area;Qaidam Basin0引言柴达木盆地高山深盆的构造格局和总体干旱缺水的沉积背景,形成了盆地边缘相带窄、“源储一体”沉积体分布广(占盆地沉积岩面积的 6
15、0%以上)的特征,油气资源勘探前景广阔,对于千万吨高原油气田建成和可持续发展具有重要的意义。英雄岭构造带隶属于柴达木盆地西部古近系新近系含油气系统,是盆地石油勘探的重要领域1-3,面积为 4 900 km2,包括狮子沟、花土沟、游园沟、油砂山、英东、干柴沟、咸水泉、油泉子、黄瓜峁、开特、油墩子等地区4。1984 年,位于狮子沟的狮 20 井在古近系下干柴沟组上段(E32)日喷油 1 138 m3、气22.7104m3,发现深层孔缝系统的碳酸盐岩油藏。由于地震资料品质差,油藏主控因素认识不清,历经 12 年探索,先后共钻探深井 16 口,均未取得明显进展。2010 年,利用二维地震老资料重新处理
16、解释成果,优选英东一号钻探砂 37 井,对 10 个层组试油均获工业油气流,发现了浅层(N22N21)碎屑岩断块油气藏,实现了勘探的重大突破。英东浅层突破后,通过持续深化碳酸盐岩成储研究,明确了咸化半深湖深湖相“源储一体”碳酸盐岩储层发育溶蚀孔洞、晶间孔、裂缝等多种储集空间,具有整体含油、构造改造调整的特征。在新认识的指导下,勘探由浅层转战深层,先后钻探 8 口千吨级高产井,在英西英中地区平面上落实了 5 个油气富集区,累计探明油气地质储量超过 7 000104t。同时,引入页岩油勘探新理念5,在深入研究和评价烃源岩的基础上,优选构造变形较弱的干柴沟地区开展源内页岩油勘探,完钻的 6 口直井 9 个层组压裂后均获工业油流,落实页岩油面积 42 km2,估算地质储量超过 3108t。截至目前,英雄岭地区累积探明石油地质储量已达 5108t,但油气发现率仍较低6-7。从英雄岭地区已知油气藏分布来看,它们并不严格受构造圈闭的控制,而且不同深度油气层的产量也存在着明显的差异,针对该区油气藏的富集规律和成藏模式尚无系统研究。通过构造演化、烃类包裹体、典型油气藏解剖等技术手段,对柴达木盆地英雄岭地