石油学报 ›› 2018, Vol. 39 ›› Issue (8): 869-875.DOI: 10.7623/syxb201808003

• 地质勘探 • 上一篇    下一篇

Bongor盆地Baobab地区潜山油气成藏期次

文志刚1, 李威1,2,3, 窦立荣1,4, 张光亚3, 程顶胜3, 杜业波3, 胡瑛3, 王利3   

  1. 1. 长江大学资源与环境学院 油气资源与勘探技术教育部重点实验室 湖北武汉 430100;
    2. 中海油研究总院有限责任公司 北京 100028;
    3. 中国石油勘探开发研究院 北京 100083;
    4. 中国石油天然气勘探开发公司 北京 100034
  • 收稿日期:2017-06-05 修回日期:2017-11-03 出版日期:2018-08-25 发布日期:2018-09-04
  • 通讯作者: 文志刚,男,1965年7月生,1985年获江汉石油学院学士学位,1997年获中国地质大学(北京)博士学位,现为长江大学教授、博士生导师,主要从事有机地球化学及石油地质学研究。Email:wzg728@sina.com
  • 作者简介:文志刚,男,1965年7月生,1985年获江汉石油学院学士学位,1997年获中国地质大学(北京)博士学位,现为长江大学教授、博士生导师,主要从事有机地球化学及石油地质学研究。Email:wzg728@sina.com
  • 基金资助:

    国家科技重大专项(2011ZX05029,2016ZX05029-005)、中国石油天然气股份有限公司科技专项(2013D-0902)资助。

Buried-hill hydrocarbon accumulation stage of Baobab area in Bongor Basin

Wen Zhigang1, Li Wei1,2,3, Dou Lirong1,4, Zhang Guangya3, Cheng Dingsheng3, Du Yebo3, Hu Ying3, Wang Li3   

  1. 1. College of Resources and Environment, Yangtze University;Key Laboratory of Exploration Technologies for Oil and Gas Resources of the Ministry of Education, Hubei Wuhan 430100, China;
    2. CNOOC Research Institute Co. Ltd., Beijing 100028, China;
    3. PetroChina Research Institute of Petroleum Exploration and Development, Beijing 100083, China;
    4. China National Oil and Gas Exploration and Development Corporation, Beijing 100034, China
  • Received:2017-06-05 Revised:2017-11-03 Online:2018-08-25 Published:2018-09-04

摘要:

Baobab潜山油藏是乍得Bongor盆地北部斜坡的主力油藏。以Baobab C-2井潜山油藏为例,从烃源岩生排烃史、构造热演化史、流体包裹体中含油包裹体颗粒指数特征、显微荧光与测温技术等方面分析其油气成藏史。埋藏史的分析结果表明,Baobab地区Mimosa组+Prosopis组主力烃源岩在约90 Ma开始生烃,并于约80 Ma开始排烃,晚白垩世末约66 Ma达到生排烃高峰期,之后由于构造抬升作用,生烃作用停止。Baobab C-2井潜山油藏经历了晚白垩世80~55 Ma的原生油气充注阶段和古近纪约30 Ma的次生油气成藏事件。在晚白垩世期间石油的充注表现为充注强度程度不同的连续过程,开始于晚白垩世80 Ma的石油充注事件以较低成熟度原油为主,而发生于约70 Ma的第二期石油充注事件则以成熟油气为主,该期充注事件是形成现今油气分布格局的主要贡献者。古近纪发生的次生成藏事件代表因构造作用而引起油气调整。

关键词: 基岩, 潜山, 油气成藏年代, Bongor盆地, 乍得

Abstract:

Baobab buried-hill reservoir is the major oil reservoir in the north slope of Bongor Basin. Taking Baobab C-2 buried-hill reservoir as an example, its hydrocarbon accumulation history is analyzed and studied in terms of the hydrocarbon generation and expulsion history of source rocks, tectonic thermal evolution history, the GOI characteristics of fluid inclusion, micro-photoluminescence, thermometric techniques and etc. Through studying burial history, it is found that the major source rocks in Mimosa Formation and Prosopis Formation of Baobab area began to generate hydrocarbon at about 90 Ma, and started to expel hydrocarbon at about 80 Ma. At about 66 Ma in the Late Cretaceous, hydrocarbon generation and expulsion reached the peak; afterwards, hydrocarbon generation ceased due to tectonic uplift. Baobab C-2 buried-hill reservoir experienced the primary oil-gas charging stage at about 80-55 Ma in the Late Cretaceous and the secondary hydrocarbon accumulation event at about 30 Ma in Paleocene. In the late Cretaceous period, the oil charging was a continuous process with different degrees of charging intensity. The oil charging event beginning at 80 Ma was dominated by low-maturity crude oil; the second stage of oil charging event happening at 70 Ma was dominated by mature oil and gas, and made a major contribution to the formation of current oil-gas distribution pattern. The occurrence of secondary accumulation event in Paleocene represents the oil-gas adjustment event resulted from tectonism.

Key words: bed rock, buried-hill, hydrocarbon accumulation age, Bongor Basin, Chad

中图分类号: