江苏金湖凹陷古近系奇碳优势和偶碳优势共存的正构烷烃
- 中国石油大学石油天然气成藏机理教育部重点实验室 北京 102249
- 收稿日期:
1900-01-01
- 修回日期:
1900-01-01
- 刊出日期:
2007-04-10
摘要: 苏北盆地金湖凹陷古近纪阜宁组二段暗色泥岩及其生成的原油中,正构烷烃系列存在着偶碳优势、奇碳优势以及二者共存的3种分布型式。本文重点探讨正构烷烃奇碳优势和偶碳优势共存的形成原因。在这类暗色泥岩与原油中,正构烷烃通常低碳数部分呈nC15、nC17优势,中碳数具有nC20、nC22优势,高碳数为nC25、nC27、nC29、nC31优势;并且具有强烈的植烷优势、较高的伽玛蜡烷指数、含有一定量β胡萝卜烷和C24四环萜烷。分析认为沉积水体环境和有机质来源的变化决定了正构烷烃的分布形式,该类正构烷烃形成于湖盆水体盐度分层的沉积环境,主要来源于湖盆内藻类和湖盆外高等植物蜡。
An nalkane Coexisting Even and Odd Carbon Number Predominace of Paleogene in Jinhu Sag
- Key Laboratory for Hydrocarbon Accumulation Mechanism of Education Ministry, China University of Petroleum, Beijing 102249
- Received Date:
1900-01-01
- Rev Recd Date:
1900-01-01
- Publish Date:
2007-04-10
Abstract: The data of source rock and oil samples reveal three distribution patterns of nalkanes in the second group of the Funing Formation in Jinhu Sag of Subei basin, eastern China. The three patterns are, respectively, the oddtoeven predominance,the eventoodd predominance, the even and odd carbon number predominance coexisting in whole carbon number. In papers, the characteristics of a nalkane coexisting even and odd carbon number predominance and its origin are investigated only. The shortchain nalkanes and longchain nalkanes are characterized by a pronounced odd carbon predominance, with the dominant carbon number of nC15, nC17 and with nC25, nC27, nC29,nC31. And the midchain nalkanes are dominated by even carbon predominance, with the dominant carbon number of nC20 and nC22.A number of biomarkers support sediments deposited in an anoxic, hypersaline lacustrine setting. These include the phytane preference, high gammacerane and the presence of βcarotene and C24tetracyclic terpane. The biomarkers are not homosphere, which shows that salinity and redox is not constant in lake. The nalkanes are mainly derived from algae in lake and macrophytes on land or around edges of the lake. The nalkane distribution patterns of the source rocks and oils studied are believed not to be dependent of the redox in depositional environments and the salinity of water body, but to be associated with original organic matter composition.
宋 宁. 江苏金湖凹陷古近系奇碳优势和偶碳优势共存的正构烷烃[J]. 沉积学报, 2007, 25(2): 307-313.
引用本文: |
宋 宁. 江苏金湖凹陷古近系奇碳优势和偶碳优势共存的正构烷烃[J]. 沉积学报, 2007, 25(2): 307-313.
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SONG Ning. An nalkane Coexisting Even and Odd Carbon Number Predominace of Paleogene in Jinhu Sag[J]. Acta Sedimentologica Sinica, 2007, 25(2): 307-313.
Citation: |
SONG Ning. An nalkane Coexisting Even and Odd Carbon Number Predominace of Paleogene in Jinhu Sag[J]. Acta Sedimentologica Sinica, 2007, 25(2): 307-313.
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