摘要
鄂尔多斯盆地的天然气勘探发现与理论认识的深化密不可分,该文以靖边气田为重点解剖对象,在对盆地古生界天然气勘探新突破认识的基础上,重新分析和梳理靖边气田天然气地球化学资料,进一步认识靖边气田的成因及其演变机制。靖边气田不同层系天然气地球化学特征与成因存在显著差异,马家沟组中下组合天然气主要与下古生界碳酸盐岩烃源形成的海相油型气有关;马家沟组上组合天然气是上古生界煤型气与下古生界油型气复合的结果,不同区域下古生界烃源贡献有差别,盆地中东部盐下天然气藏的下古生界烃源贡献不容忽视。下古生界存在有效烃源,马家沟组的干酪根、分散可溶有机质和酸溶有机质是构成烃源物质的3个重要组成部分。有机酸盐生烃和TSR作用是造成马家沟组烃源岩无机碳同位素显著负漂的主要原因,同时也是马家沟组烃源岩生烃的主要证据。
The discovery of Natural gas exploration in Ordos Basin is inseparable from innovation and deepening of theoretical knowledge.In this paper,the Jingbian gas field is taken as the key anatomical object,based on the new breakthrough understanding of the Paleozoic natural gas exploration,the natural gas geochemical data of the Jingbian gas field are reanalyzed and sorted out to further study the genesis and evolution mechanism of the Jingbian gas field.The results show that there are significant differences in the geochemical characteristics and genesis of natural gas in different strata of Jingbian gas field:The natural gas in the lower and middle assemblages of Majiagou Formation is mainly related to the marine oil-type gas formed by the Lower Paleozoic carbonate sourcerocks;the natural gas in the upper assemblage of Majiagou Formation is the result of the combination of Upper Paleozoic coal-type gas and Lower Paleozoic oil-type gas,the contribution of Lower Paleozoic hydrocarbon source in different regions is different,which in central-eastern Ordos Basin cannot be ignored.There are effective hydrocarbon sources in the Lower Paleozoic,as the kerogen,dispersed soluble organic matter and acid soluble organic matter of Majiagou Formation are three important components of hydrocarbon sources.The hydrocarbon generation by organic acid salts and TSR(Thermochemical Sulfate Reduction)are the main reasons for the significant negative drift of inorganic carbon isotopic composition in Majiagou Formation source rocks,and also the main evidence of hydrocarbon generation in Majiagou Formation source rocks.
作者
刘文汇
王晓锋
张东东
蔡郑红
罗厚勇
陈晓艳
王桐
李芙蓉
张雯
李福奇
LIU Wenhui;WANG Xiaofeng;ZHANG Dongdong;CAI Zhenghong;LUO Houyong;CHEN Xiaoyan;WANG Tong;LI Furong;ZHANG Wen;LI Fuqi(State Key Laboratory of Continental Dynamics,Department of Geology,Northwest University,Xi′an 710069,China;Petroleum Exploration&Production Research Institute,SINOPEC,Beijing 100083,China;Exploration and Development Research Institute of PetroChina Changqing Oilfield Company,Xi′an 710018,China)
出处
《西北大学学报（自然科学版）》
CAS
CSCD
北大核心
2022年第6期943-956,共14页
Journal of Northwest University（Natural Science Edition）
基金
中国石油长庆油田分公司重大科技专项(ZDZX2021-03)
国家自然科学基金(41972134)。
关键词
靖边气田
天然气地球化学
碳酸盐岩烃源
TSR作用
Jingbian gas field
natural gas geochemistry
carbonate hydrocarbon source
Thermochemical Sulfate Reduction
