塔里木盆地下古生界深层烃源岩和原油生物标志物类型划分及油源  

Biomarker classifications of Lower Paleozoic deep source rocks and crude oils from the Tarim Basin and oil sources

作　　者：李梦勤 姚超[1] 陈方方[1] 何涛华 赵龙飞 肖春艳[1] 王青红 李正阳 黄亚浩 文志刚[2] LI Mengqin;YAO Chao;CHEN Fangfang;HE Taohua;ZHAO Longfei;XIAO Chunyan;WANG Qinghong;LI Zhengyang;HUANG Yahao;WEN Zhigang(Petroleum Exploration&Production Research Institute,Tarim Oilfield Company,PetroChina,Korla 841000,China;Key Laboratory of Oil and Gas Resources and Exploration Technology,Ministry of Education,Yangtze University,Wuhan 430100,China;National Key Laboratory of Deep Oil and Gas,China University of Petroleum(East China),Qingdao 266580,China)

机构地区：[1]中国石油塔里木油田分公司勘探开发研究院,新疆库尔勒841000 [2]教育部油气资源与勘探技术重点实验室(长江大学),湖北武汉430100 [3]深层油气国家重点实验室(中国石油大学(华东)),山东青岛266580

出　　处：《天然气地球科学》2025年第1期166-182,共17页Natural Gas Geoscience

基　　金：国家自然科学基金项目(编号:42272160);中国石化油气成藏重点实验室开放基金(编号:33550007-22-ZC0613-0040)联合资助.

摘　　要：为探索下古生界深层复杂原油的来源,对塔里木盆地下古生界烃源岩及原油开展了系统的地球化学分析。通过自然演化—热模拟实验对比,揭示了部分芳烃类指标的高稳定性,尤其是1⁃烷基⁃2,3,6⁃芳基类异戊二烯(2,3,6⁃AIPs)具有极强的抗次生改造能力。综合评价生烃潜力明确了5套[下寒武统玉尔吐斯组(Є_(1)y)、中下奥陶统黑土凹组(O_(1⁃2h))、西合休剖面中奥陶统(O_(2)x)、中上奥陶统萨尔干组(O_(2⁃3)s)和上奥陶统良里塔格组(O_(3)l)]富有机质烃源岩,并根据稳定的芳烃指标将其划分为“低盐—绿藻”型、“高盐—甲藻”型和“透光厌氧—绿硫菌”型3类,将原油划分为“透光厌氧—绿藻”型和“透光厌氧—绿硫菌”型2类。其中,“透光厌氧—绿硫菌”型烃源岩主要发育于Є_(1)y,与盆地内(塔中、塔北地区等)几乎所有原油类似,都含有2,3,6⁃AIPs。油源对比和混源油定量解析也证实该类烃源岩对盆地内原油的重要贡献。因此,后期精细刻画该类含特殊生源—环境组合烃源岩的空间展布将会为研究区甚至全球类似盆地深层复杂原油的精准勘探提供重要参考。To elucidate the provenance of intricate deep crude oils in the Lower Paleozoic strata,in this paper,a systematic geochemical analysis of Lower Paleozoic source rocks and crude oil samples in Tarim Basin has been carried out.The juxtaposition of samples subjected to natural evolutionary processes and thermal simulation ex⁃periments unveiled that certain aromatic indices exhibit remarkable stability,particularly 1-alkyl-2,3,6-aryl iso⁃prenoids(2,3,6-AIPs),which demonstrates pronounced resistance to anti-secondary-alteration.A comprehen⁃sive assessment of the hydrocarbon generation potential of Lower Paleozoic source rocks identified five series of organically enriched strata(Lower Cambrian Yuertus Formation(Є_(1)y),Middle-Lower Ordovician Heituao Formation,Middle Ordovician from the Xihexiu section,Middle-Upper Ordovician Sargan Formation,and Up⁃per Ordovician Lianglitage Formation).These were categorized into three distinct groups:“low salt-green al⁃gae”,“high salt-dinoflagellates”,and“photic-zone euxinia(PZE)-green sulfur bacteria(GSB),”predicated on the presence of stable aromatic biomarkers,including 2,3,6-AIPs.And crude oils were categorized into two dis⁃tinct groups:PZE-green algae oil and PZE-GSB oil.Notably,PZE-GSB source rocks(mainly developed from theЄ_(1)y)contained abundant 2,3,6-AIPs,showing similarity to almost all crude oils from the Tazhong and Ta⁃bei areas,Tarim Basin.Through oil-source correlation and the quantitative deconvolution of mixed crude oils,it was ascertained that the source rock harboring 2,3,6-AIPs likely plays a pivotal role in the substantial contri⁃butions to the extant deep crude oil reserves in the Tarim Basin.Therefore,finely determining the spatial distri⁃bution of this source rock developed under the special biological-environmental condition(PZE-GSB),in the next stage,would provide significant reference for the targeted exploration of deep complex crude oil in the Lower Paleozoic from the Tarim Basin and even the world.

关 键 词：1⁃烷基⁃2 3 6⁃芳基类异戊二烯 绿硫菌 透光厌氧环境 抗次生改造能力 深层油气勘探 塔里木盆地 

分 类 号：TE122.113[石油与天然气工程—油气勘探]