石油学报 ›› 2011, Vol. 32 ›› Issue (1): 49-53.DOI: 10.7623/syxb201101007

• 地质勘探 • 上一篇    下一篇

柴达木盆地北缘东段大煤沟组一段优质烃源岩

阎存凤 1,2  袁剑英 1  陈启林 1  邵宏舜 3  张正刚 1   

  1. 1中国石油勘探开发研究院西北分院  甘肃兰州  730020; 2中国地质大学  湖北武汉  430074; 3中国科学院油气资源研究重点实验室  甘肃兰州  730000
  • 收稿日期:2010-07-25 修回日期:2010-09-16 出版日期:2011-01-25 发布日期:2011-03-23
  • 通讯作者: 阎存凤
  • 作者简介:阎存凤,女,1964年8月生,1987年毕业于兰州大学地质系,2009年获中国地质大学博士学位,现为中国石油勘探开发研究院西北分院高级工程师,主要从事地层古生物、石油地质研究工作。
  • 基金资助:

    中国石油天然气股份有限公司“柴达木盆地油气勘探开发关键技术研究” 项目(07-01Z-01-04)资助。

Discovery of the high-quality source rock of the first member of Dameigou Formation in the east part of the northern Qaidam Basin

YAN Cunfeng 1,2  YUAN Jianying 1  CHEN Qilin 1  SHAO Hongshun 3  ZHANG Zhenggang 1   

  • Received:2010-07-25 Revised:2010-09-16 Online:2011-01-25 Published:2011-03-23

摘要:

柴达木盆地北缘地区的中下侏罗统是主要的油气源岩,而其中的大煤沟组七段是优质油气源岩。为了进一步评价柴达木盆地北缘东段侏罗系生烃能力,系统采集了大煤沟剖面中下侏罗统大煤沟组的泥岩、油页岩、碳质泥岩、煤岩等样品,并进行了系统的常规的有机地球化学分析(有机碳,S1+S2,I H,沥青A,总烃,H/C与O/C值,干酪根,碳同位素组成δ13C,生物标志化合物规则甾烷的组成等)。结果表明,大煤沟组一段与七段一样,是优质油气源岩,这是柴达木盆地北缘地区的新发现。大煤沟组孢粉的显微沉积有机质组成及有机质类型的研究也证实了上述结论。在对盆地中-下侏罗统进行油气资源评价及勘探部署时,对大煤沟组一段的优质油气源岩应给予足够的重视。

关键词: 优质油气源岩, 有机地球化学, 大煤沟组, 中-下侏罗统, 柴达木盆地北缘东段

Abstract:

It is generally thought that the lower-middle Jurassic is the major source rock in the northern Qaidam Basin, of which the seventh member of the Dameigou Formation is a high-quality source rock. Aiming at further evaluating the hydrocarbon-generative potential of the lower-middle Jurassic in the east part of the northern Qaidam Basin, the present study systematically sampled mudstones,oil shales,black mudstones and coals from the lower-middle Jurassic Dameigou Formation and performed conventional geochemical analyses, including organic carbon,S1+S2,I H,bitumen A,total hydrocarbon,the ratio of H/C and O/C,carbon isotopic composition of kerogen (δ13C),composition of regular steranes and etc.. The results showed that the hydrocarbon-generative potential of the first member of the Dameigou Formation was as good as that of the seventh member,which was the first positive recognition on source rocks of the first member of the Dameigou Formation in the northern Qaidam Basin. This recognition was also supported by the palynofacies and kerogen type investigations of the Dameigou Formation. Therefore, it is suggested that the first member of the Dameigou Formation should deserve more attentions in the evaluation and exploration of the lower-middle Jurassic in the east part of the northern Qaidam Basin.

Key words: high-quality source rock, organic geochemistry, Dameigou Formation, lower-middle Jurassic, east part of the northern Qaidam Basin