准噶尔盆地南缘天然气成藏及勘探方向  

The accumulation of natural gas and potential exploration regions in the southern margin of the Junggar basin

作　　者：陈建平[1,2,3] 王绪龙[4] 倪云燕[1,2,3] 向宝力[4] 廖凤蓉 廖键德[4] CHEN Jianping;WANG Xulong;NI Yunyan;XIANG Baoli;LIAO Fengrong;LIAO Jiande(PetroChina Re sea rch Institute of Petroleum E.xploration and Development,Beijing,100083;Stale Key Laboratory of Enhanced Oil Recovery,Beijing,100083;Key laboratory of Petroleum Geochernistry of CNPC ,Brijing,100083,China;PetroChina Xinjiang Oilfield Company ,Karamay,Xinjiang,834000)

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]提高石油采收率国家重点实验室,北京100083 [3]中国石油天然气集团公司油气地球化学重点实验室,北京100083 [4]中国石油新疆油田公司,新疆克拉玛依834000

出　　处：《地质学报》2019年第5期1002-1019,共18页Acta Geologica Sinica

基　　金：中国石油天然气股份有限公司科学研究与技术开发项目(编号06-01A-01-02;2016A-0202)资助成果

摘　　要：准噶尔盆地南缘地区与塔里木库车坳陷有着相似的沉积地层和构造演化历史,但是天然气勘探始终未取得重大突破。本文在南缘地区天然气成因类型与气源判识的基础上,分析该地区天然气成藏条件,探讨有利勘探方向与目标层系。结果表明,南缘地区天然气存在煤型气、混合气与油型气三类,且以煤型气和混合气为主;侏罗纪煤系为该地区主要的天然气源岩,其大量生气期与背斜构造形成期相匹配,构成最佳源灶-圈闭成藏组合;二叠系湖相和上三叠统湖相-湖沼相烃源岩也是重要的天然气源岩,其主要生气期在中部地区早于绝大多数背斜构造形成期,而在西部地区与背斜构造形成期相匹配。南缘地区生烃物质基础好于库车坳陷,只是主要气源岩侏罗纪煤系的成熟度略低于库车坳陷,盖层封盖性和储层发育规模略逊于库车坳陷,但仍具备形成大规模油气田的成藏条件。深层二叠系-侏罗系-白垩系成藏组合是最为有利的天然气勘探目标层系,西部是寻找和发现侏罗纪煤系和二叠系湖相油气藏的有利目标区域,中部是寻找和发现侏罗纪煤系天然气藏的有利目标区域。中浅层白垩系-新近系成藏组合是次要的天然气勘探目标层系,具有寻找和发现一定规模天然气藏的潜力。高探1井获得重大突破充分表明制约南缘天然气勘探大发现的因素不是气源规模、运移通道、储层物性和盖层封闭性,而是有效圈闭的落实、钻井工程技术及勘探工作量的投入。The southern margin of the Junggar basin has the similar history of sediment and tectonic evolution with the Kuqa depression of Tarim basin, but has never made a great breakthrough in natural gas exploration. Based on the results of genetic type and origin of the natural gas, this paper discusses the conditions for natural gas generation and accumulation compared with the Kuqa depression, and the favorable exploration regions and potential target in the region. The results show that the natural gases in the southern margin are dominated by thermogenic wet gas, which are divided into three types, coal-derived gas, mixed gas and oil-associated gas, and are dominated by former two types. The Jurassic coal measures is the main natural gas source rocks in the southern margin, and its main period of gas generation matches the formation epoch of the anticline structures, which constitutes the best source-trap combination for gas accumulation. The Permian lacustrine and Upper Triassic lacustrine-limnetic facies source rocks may also be important natural gas source rocks, whose main period of gas generation is earlier than the formation epoch of most anticline structures in the central region, but coincides with the epoch of anticline formation in the western region. Compared with the Kuqa Depression, the southern margin has batter material base of hydrocarbon generation than the Kuqa depression, but the maturity of the source rocks of the Jurassic coal measures is slightly lower than that of the Kuqa depression, the capping of the caprock and the scale of reservoir rock are slightly inferior to those of the Kuqa depression. The southern margin still has the conditions for forming large-scale oil and gas fields. The combination of the Permian-Jurassic-Cretaceous in the deep is the most favorable system for natural gas exploration, where the western part is a favorable target area for finding and discovering Jurassic coal-derived oil and gas reservoirs, and the middle part is a favorable target area for finding and discove

关 键 词：准噶尔盆地南缘 天然气 成因类型 侏罗纪煤系 天然气成藏 勘探方向 库车坳陷 

分 类 号：P618.13[天文地球—矿床学]