准噶尔盆地盆1井西凹陷石炭系火山岩凝析气藏的发现与勘探启示  

Discovery and exploration enlightenment of Carboniferous volcanic condensate gas reservoirs in western well Pen-1 sag,Junggar Basin

作　　者：卞保力[1] 刘海磊[1] 蒋文龙[1] 王学勇[1] 丁修建 BIAN Baoli;LIU Hailei;JIANG Wenlong;WANG Xueyong;DING Xiujian(Research Institute of Exploration and Development,PetroChina Xinjiang Oilfield Company,Karamay 834000,Xinjiang,China;School of Geosciences,China University of Petroleum(East China),Qingdao 266580,Shandong,China)

机构地区：[1]中国石油新疆油田公司勘探开发研究院,新疆克拉玛依834000 [2]中国石油大学(华东)地球科学与技术学院,山东青岛266580

出　　处：《岩性油气藏》2024年第3期96-105,共10页Lithologic Reservoirs

基　　金：中国石油天然气股份有限公司“十四五”前瞻性基础性技术攻关项目“陆相深层超深层油气富集规律与勘探评价技术研究”(编号:2021DJ0206)资助。

摘　　要：准噶尔盆地石炭系火山岩油气藏是油气勘探的重点领域之一。根据录测井资料、地球化学分析数据及岩石薄片鉴定资料,结合地球物理方法,厘清了准噶尔盆地盆1井西凹陷石炭系火山岩油气成藏的主控因素,总结出深层火山岩气藏富集规律,明确了有利勘探方向。研究结果表明:(1)准噶尔盆地盆1井西凹陷风城组烃源岩厚度为100~300 m,面积约为5 400 km2,整体进入生凝析油—干气阶段,生气强度大于20×108m3/km2,为凹陷提供了丰富的天然气源。(2)研究区石炭系火山岩岩性复杂,爆发作用形成的安山质火山角砾岩受到风化淋滤作用,可形成物性较好的风化壳型储层。石炭系—二叠系大型不整合面和广泛发育的深大断裂是重要的输导体系,二叠系上乌尔禾组泥岩作为区域盖层,为凝析气成藏提供了保存条件,油藏主要分布在高部位,气藏分布于低部位。(3)通过“两宽一高”(宽方位、宽频带、高密度)技术,提高地震成像精度,联合时-频电磁技术(TFEM),实现了石炭系火山岩的精细刻画,为深层油气藏的勘探提供了有力支撑。石西16井的重大突破,证实了盆1井西凹陷石炭系火山岩具有巨大的勘探潜力。Carboniferous volcanic reservoir in Junggar Basin is one of the key fields of oil and gas exploration.Based on logging data,geochemical analysis data and rock thin section identification,combined with geophysical methods,the main controlling factors of Carboniferous volcanic oil and gas accumulation in western well Pen-1 sag in Junggar Basin were clarified,the enrichment rules of deep volcanic reservoirs were summarized,and the favorable exploration directions were defined.The results show that:(1)The source rocks of Fengcheng Formation in western well Pen-1 sag of Junggar Basin are 100-300 m thick and cover an area of about 5400 km2,and enter the stage of generating condensate oil and dry gas as a whole,with a gas generation intensity greater than 20×108m3/km2,providing abundant natural gas sources for the sag.(2)The lithologies of the Carboniferous volcanic rocks in the study area are complex,and the andesitic volcanic breccias formed by volcanic eruptions are weathered and leached,which can form weathered crust-type reservoirs with high reservoir properties.The large unconformity between Carboniferous and Permian and widely developed deep and large faults are important transport systems.The mudstones of the upper Urho Formation of Permian serve as a regional cap rock,providing preservation conditions for condensate gas accumulation.Oil reservoirs are mainly developed in high position,while gas reservoirs are developed in low position.(3)Through the“WBH”(wide-azimuth,broadband,and high-density)technology,the accuracy of seismic imaging has been improved,and the timefrequency electromagnetic technology(TFEM)was combined to achieve fine characterization of Carboniferous volcanic rocks,providing a favorable support for the exploration of deep oil and gas reservoirs.The major breakthrough of well Shixi 16 has confirmed the great exploration potential of Carboniferous volcanic rocks in western well Pen-1 sag.

关 键 词：凝析气藏 火山岩 风城组烃源岩 上乌尔禾组泥岩盖层 不整合面 深大断裂 “两宽一高”技术 时-频电磁技术 石炭系 盆1井西凹陷 准噶尔盆地 

分 类 号：TE122.1[石油与天然气工程—油气勘探] P618.130.1[天文地球—矿床学]