辽河盆地煤系地层中特高含量的二萜类及其地质意义
- 1. 中国科学院兰州地质研究所气体地球化学国家重点实验室;
- 2. 辽河石油管理局勘探开发研究院
作者简介:
妥进才,男,1964年出生,博士研究生,副研究员,有机地球化学和石油地质
- 收稿日期:
1998-03-04
- 修回日期:
1998-12-14
- 刊出日期:
1999-06-10
摘要: 从辽河盆地东部凹陷下第三系沙三段煤系烃源岩中检出了特高含量的海松烷,脱氢松香烷等三环二萜烷和扁枝烷等四环二萜烷类化合物,此外还检测到了奥利烯、乌散烯等罕见的三萜类。上述三类化合物尽管出现在同一套地层中,但它们的主要来源并不完全相同,其中三环二萜和四环二萜类分别以裸子植物和蕨类植物为主要来源,而五环三萜类则主要来源于被子植物。说明辽河盆地下第三系沙三段煤系地层中母质输入的多样性和复杂性。
High Abundance Diterpenoids and Their Geological Significance in Coal Measure Strata, Liaohe Basin
- 1. State key laboratory of Gas-geochemistry Lanzhou Institute of Geology Chinese Academy of Sciences Lanzhou 730000
- Received Date:
1998-03-04
- Rev Recd Date:
1998-12-14
- Publish Date:
1999-06-10
Abstract: Tricyclic diterpanes such as pimarane, dehydrabieatane and simonelli te and tetracyclic diterpanes such as phyllocladene are most common biomarkers i n coal and other terrestrial source rocks and oils, but in most case they are no t high in abundance. In this study we examined some Chinese coals and terrestria l sediments for the highly presence of tricyclic and tetracyclic diterpenoid hyd rocarbons, and have assigned structures to the diterpanes by mass spectra. The s amples were collected from the third Member of Shahejie Formation, Low-Eogene, E astern Depression, Liaohe Basin. The sedimentary environments for the samples ar e fresh water lacustrine bog and flood plain facies. Organic petrologic analyses show that the organic macerales for the coal measure source rocks are mainly co mposed of vitrinite, contented up to 70% or even high to 90 %, while the content s of exinite, inertinite and sapropelic material are very low. The Ro for the sa mples under study varies from 0.475%to 0.539%, so the organic matters from those samples are generally in immature and lower thermal evolution stages. Fo r all of the samples, C20+ n-alkanes predominate over C15~ C19 n-alkanes and the nC29 or nC31 n-alkanes are the prominent peaks . All of the OEP values for the samples are large than 7 and the CPI values are larger than 3. Therefore the alkanes also show an obviously immatures to low-mature thermal evolution. In all of the samples pristane is the most abun dant alkane of the saturated hydrocarbon fractions. Pristane/phytane ratios all are larger than 2. This is also the typical isoprenoid hydrocarbon distribution characteristic for coal measure source rocks. High abundance tricyclic diterpane s such as pimarane and dehydrabieatane and tetracyclic diterpanes such as phyllo cladene are detected from the samples. Besides, some special biomarkers such as oleanene, ursene and other pentacyclic triterpenoids are also detected from thos e samples. Although thre kinds of biomarkers are detected in the same strata, t hey come from different plants. Tricyclic diterpanes and tetracyclic diterpanes mainly come from gymnosperm (in particular the conifer), petridophyte, bryophyte and pteridophyte respectively, whereas pentacyclic triterpenoids mainly come fr om angiosperm. show that the input of organic matter in the coal source rocks, the third Member of Shahejie Formation, Low-Eogene, Eastern Depression, Liaohe Ba sin,is of obvions diversification and complexity.
妥进才, 王先彬, 陈践发, 郭克园, 陈振岩, 朴明植. 辽河盆地煤系地层中特高含量的二萜类及其地质意义[J]. 沉积学报, 1999, 17(2): 285-290.
引用本文: |
妥进才, 王先彬, 陈践发, 郭克园, 陈振岩, 朴明植. 辽河盆地煤系地层中特高含量的二萜类及其地质意义[J]. 沉积学报, 1999, 17(2): 285-290.
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TUO Jin cai, WANG Xian bin, CHEN Jian fa, GUO Ke yuan, CHEN Zhen yan, PIAO Ming zhi. High Abundance Diterpenoids and Their Geological Significance in Coal Measure Strata, Liaohe Basin[J]. Acta Sedimentologica Sinica, 1999, 17(2): 285-290.
Citation: |
TUO Jin cai, WANG Xian bin, CHEN Jian fa, GUO Ke yuan, CHEN Zhen yan, PIAO Ming zhi. High Abundance Diterpenoids and Their Geological Significance in Coal Measure Strata, Liaohe Basin[J]. Acta Sedimentologica Sinica, 1999, 17(2): 285-290.
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