摘要
为了明晰准噶尔盆地东道海子凹陷深层油气来源及成藏模式,采用显微组分分析、正构烷烃与生物标志化合物测试、流体包裹体均一化温度测定等方法,对比分析了凹陷带、斜坡带及周缘凸起带烃源岩与油气的地球化学特征。研究结果表明:①东道海子凹陷石炭系烃源岩以腐殖型干酪根为主,生气潜力显著,二叠系中统下乌尔禾组烃源岩为混合型干酪根,兼具生油与生气能力,并且凹陷带有机质热演化成熟度(Ro)显著高于凸起带;②滴南凸起东段与白家海凸起原油为下乌尔禾组成熟油与石炭系原油混合成因,天然气以石炭系过成熟干气为主且混源少量二叠系天然气,斜坡带与凹陷带原油主要来源于下乌尔禾组成熟—高成熟油且混源少量石炭系原油,天然气为下乌尔禾组与石炭系混合气;③凹陷带与斜坡带存在三期油气充注(早三叠世—中三叠世、晚三叠世—中侏罗世、晚侏罗世—早白垩世),凸起带以两期充注为主;④烃源岩厚度与有机碳含量自凸起带向凹陷带递增(凹陷带下乌尔禾组泥岩厚度达536 m),生物标志化合物揭示凹陷带水生生物输入更显著。结论认为,东道海子凹陷深层油气成藏受多期构造活动控制,凹陷带高成熟烃源岩与断裂系统共同主导了油气差异分布,为腹部深层油气勘探提供了“源—断—储”耦合的成藏模式依据。
To clarify the source and accumulation model of deep oil and gas in the Dongdaohaizi Sag of the Junggar Basin,the geochemical characteristics of source rocks and hydrocarbons in sag,slope,and peripheral uplift zones were comparatively investigated through maceral analysis,n-alkane and biomarker testing,and fluid inclusion homogenization temperature measurement.The research results are obtained in four aspects.(i)The Carboniferous source rocks in the Dongdaohaizi Sag are mainly composed of humic kerogen with remarkable potential of gas generation,while the source rocks in the Middle Permian Lower Wuerhe Formation are represented by hybrid kerogen capable of both oil and gas generation.Moreover,the sag zone is found with a much higher thermal maturity of organic matters(Ro)than the uplift zone.(ii)The crude oil in the eastern Dinan Uplift and Baijiahai Uplift is a mixture of mature oil from the Lower Wuerhe Formation and the Carboniferous crude oil,with natural gas primary consisting of over-mature Carboniferous dry gas,mixed with minor Permian natural gas.The crude oil in the slope and sag zones mainly originates from mature to highly-mature oil from the Lower Wuerhe Formation,mixed with minor Carboniferous oil,while the natural gas is a mixture from the Lower Wuerhe Formation and the Carboniferous.(iii)There are three phases of hydrocarbon charging in the sag and slope zones(i.e.,Early Triassic-Middle Triassic,Late Triassic-Middle Jurassic,and Late Jurassic-Early Cretaceous),and two phases of charging in the uplift zone.And(iv)the thickness and total organic carbon content of source rocks increase from the uplift zone toward the sag zone,with the mudstone thickness of the Lower Wuerhe Formation in the sag zone reaching 536 m,and the biomarkers reveal that the input of aquatic organisms is more significant in the sag zone.In conclusion,the deep oil and gas accumulation in the Dongdaohaizi Sag is controlled by multi-phase tectonic activities,and the high-maturity source rocks and fault systems in the sag zone jointly dominate the differential distribution of hydrocarbons,providing a referential“source-fault-reservoir”coupled accumulation model for deep oil and gas exploration in the interior basin.
作者
郭瑞超
王娟
贾凡建
范婕
罗力元
向忠强
李勇
GUO Ruichao;WANG Juan;JIA Fanjian;FAN Jie;LUO Liyuan;XIANG Zhongqiang;LI Yong(Exploration and Development Research Institute,Sinopec Shengli Oilfield Company,Dongying,Shandong 257015,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu,Sichuan 610500,China;Sichuan Key Laboratory of Natural Gas Geology,School of Geosciences and Technology,Southwest Petroleum University,Chengdu,Sichuan 610500,China;School of Geosciences and Technology,Southwest Petroleum University,Chengdu,Sichuan 610500,China)
出处
《天然气勘探与开发》
2025年第4期1-14,共14页
Natural Gas Exploration and Development
基金
中国石化科技攻关项目“中西部三大叠合盆地及周缘资源评价”(编号:P23244)和“准噶尔盆地侏罗系自源系统成烃成藏及勘探方向”(编号:P24017)
中国石化科技基础前瞻项目“准噶尔盆地超深层油气源识别及多相态烃类赋存机理”(编号:P24184)
胜利油田科技攻关项目“阜康—东道海子凹陷侏罗系源储演化与油气运聚方向”(编号:YKK2403)。
