吐哈盆地台北凹陷下侏罗统原油地球化学特征及油—源精细对比  

Geochemical characteristics of the Lower Jurassic hydrocarbon and fine oil-source correlation in Taibei Sag, Turpan-Hami Basin

作　　者：王柏然 黄志龙[1,2] 肖冬生[3] 贾雪丽[3] 曾文人 屈童 杨易卓 Boran WANG;Zhilong HUANG;Dongsheng XIAO;Xueli JIA;Wenren ZENG;Tong QU;Yizhuo YANG(College of Geosciences,China University of Petroleum(Beijing),Beijing 102249,China;State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum(Beijing),Beijing 102249,China;Research Institute of Exploration and Development,Tuha Oilfield Company,CNPC,Hami 839009,China)

机构地区：[1]中国石油大学(北京)地球科学学院,北京102249 [2]中国石油大学(北京)油气资源与探测国家重点实验室,北京102249 [3]中国石油吐哈油田公司勘探开发研究院,新疆哈密839009

出　　处：《天然气地球科学》2024年第1期164-175,共12页Natural Gas Geoscience

基　　金：中国石油吐哈油田公司勘探开发研究院项目“台北凹陷三工河组致密砂岩油气成藏过程与差异富集机理研究”(编号:YJYHZC2022-004)资助~~。

摘　　要：新疆东部吐哈盆地台北凹陷下侏罗统致密油性质及分布规律复杂,下侏罗统三工河组及八道湾组烃源岩的沉积环境及物源特征差异明显。应用地球化学手段,对吐哈盆地下侏罗统原油类型进行划分并进行油—源精细对比,同时梳理油气分布与其来源的差异性。研究结果表明:台北凹陷胜北—丘东洼陷三工河组原油以凝析油为主,根据原油饱和烃及芳香烃生物标志物特征及其差异,可划分为两大类三小类原油。其中Ⅰ类和Ⅱ类原油的划分主要依据其有机质来源类型的差异,Ⅰ类原油的陆源高等植物贡献较多且形成于淡水沉积环境,与研究区下侏罗统八道湾组煤系烃源岩具有明显的亲缘关系,该类原油样品主要分布在丘东洼陷区、温吉桑和北部山前带等构造高部位,成熟度较低。Ⅱ类原油均为三工河组湖相泥岩贡献,其中Ⅱ1类原油主要分布在丘东洼陷区三工河组二段的致密砂岩储层中,生烃母岩形成时期水体盐度较高,干酪根以低等水生生物贡献为主,与三工河组湖相泥岩有明显亲缘关系,Ⅱ2类原油主要分布于胜北洼陷区三工河组致密储层中,其主要来自于胜北洼陷区三工河组泥岩。研究证实了台北凹陷三工河组湖相泥岩除了作为盖层外,同时可以作为生油岩对致密油气有一定的贡献,其对深化台北凹陷油源的新认识和油气藏预测有较大指导作用。The properties and distribution of Lower Jurassic tight oil in Taibei Sag of Turpan-Hami Basin are relatively complex.The sedimentary environment and biological origin of source rocks in the Lower Jurassic Sangonghe Formation and Badaowan Formation are significantly different.Several types of Lower Jurassic crude oil in Turpan-Hami Basin are determined and detailed oil-source correlation is carried out by geochemical methods,and the differences between oil and source rock distribution are analyzed.The results show that the crude oil in the Sangonghe Formation of Shengbei-Qiudong sub-sags is mainly condensate oil,which can be divided into two categories(three subcategories)according to the characteristics and differences of the biomarkers of saturated hydrocarbons and aromatics.The typeⅠcrude oil is mainly distributed in the Qiudong sub-sag,the Wenjisang area and the Northern uplift belt with low maturity,and has a significant relationship with the local coaly source rocks of the Lower Jurassic Badaowan Formation.The distinction between type I and type II crude oils is mainly based on their different origin of the organic matter.The typeⅡ1 crude oil is mainly distributed in the tight sandstone reservoirs of the second member of the Sangonghe Formation in the depression area of the Qiudong sub-sag.The biogenic characteristics of the typeⅡ1 crude oil indicate that it originated from source rock that developed in the water body with relatively high salinity and has more contributions from lower aquatic organisms,which is related to the lacustrine mudstone of the Sangonghe Formation.The typeⅡ2 crude oil is derived from the depression area of the Shengbei sub-sag,which is contributed by the mudstone of Sangonghe Formation.This study confirms that the lacustrine mudstone of the Sangonghe Formation in the Taibei Sag can contribute to the tight oil reservoirs not only as cap rock,but also as source rock.This understanding has a great guiding role in deepening the new understanding of hydrocarbon sources and favora

关 键 词：地球化学特征 原油成因类型 油—源对比 三工河组 八道湾组 台北凹陷 吐哈盆地 

分 类 号：TE122.113[石油与天然气工程—油气勘探]