富有机质的黑色页岩和油页岩的有机岩石学特征与生、排烃意义
- 中国科学院广州地球化学研究所有机地球化学国家重点实验室 广州 510640
- 收稿日期:
1900-01-01
- 修回日期:
1900-01-01
- 刊出日期:
2006-02-10
摘要: 用近代有机岩石学与有机地球化学分析相结合的方法,对比研究了我国四川盆地等下古生界富有机质沉积的海相黑色页岩,和渤海湾盆地下第三系湖相油页岩的显微有机组成特征与热演化生烃、排烃作用的关系。观测分析结果表明:黑色页岩热演化程度很高,目前热解烃含量很低,但残余有机碳含量达1%~3%,黑色页岩中保存了早期生油阶段由无定型有机质生油作用转化而形成的微粒体有机质,和未排出的石油演变而来的残余沥青,表明其为原始生烃性能很好的烃源岩。根据黑色页岩中微粒体和残余沥青的含量,可用来了解已生—排烃量和再沉降埋深过程中古油藏储层沥青、微粒体和残余沥青再生气对古生界碳酸盐气藏的贡献。富有机质沉积的下第三系湖相油页岩热演化程度不高,游离烃(S1为0.2~1.4 mg/g)和热解烃(S2为8~44 mg/g),有机碳含量达2.4%~8%,是生油性能很好的烃源岩,油页岩中不仅存在强荧光的藻和无定型有机质,而且油页岩的纹层中广泛存在富有机质的荧光沥青,反映了有利于排烃运移的信息,表明是本区生油贡献最大的烃源岩。富有机质黑色页岩和油页岩的沉积结构构造特征、有机质的赋存形式、热演化中变化过程的对比观察结果表明:其生烃、排烃作用既有很多相似性,又有一定差别。
Organic Petrological Study on Hydrocarbon Generation and Expulsion from Organicrich Black Shale and Oil Shale
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640
- Received Date:
1900-01-01
- Rev Recd Date:
1900-01-01
- Publish Date:
2006-02-10
Abstract: By utilizing both modern organic petrological and organic geochemical analytical methods, a comparative study was carried out on the maceral ingredients of the Lower Paleozoic organicrich marine black shale in Sichuan Basin and the Paleogene lacustrine oil shale in Bohai Gulf Basin, and on their relationship with thermal evolution, hydrocarbon generation and expulsion. Our observation and the analytical results demonstrate that the black shale are characterized by high degree of thermal evolution and currently very low concentration of hydrocarbons derived from pyrolysis, and are favorablesource rocks in terms of primary hydrocarbon generation capacity, since they generally contain a relic organic carbon content up to 1%3%. However, the black shale retains a great amount of particulate organicmaterials originated from amorphous organics and relict bitumen derived from oil that has not been expelled completely at the earlier stage of oil generation in preCaledonian. Based on the contents of microsomers and relict bitumen in black shale, the amount of hydrocarbon generation and expulsion in the marine black shale can be calculated, and the contribution of gas regeneration in the reservoir bitumen, particulate organics and relict bitumen in old petroleum deposits toward the formation of the Paleozoic carbonate gas reservoirs in the study area can thus be inferred.
The organicrich Paleogene lacustrine oil shale don't show high degree of thermal evolution, since they are characterized by very high contents in bothS1(free hydrocarbon) and S2(pyrolyzed hydrocarbon), which are 2.048.06 mg.g-1and 8.444.65 mg.g-1, respectively, from pyrolytic analyses. The algae and amorphous organics in oil shale generally show strong yellow fluorescence. Also, extensive fluorescence can be observed among a great amount of laminae and mineral crystallites. These results illustrate that the oil shale are important source rocks at the stage of hydrocarbon generation and expulsion in the study area.
曾庆辉. 富有机质的黑色页岩和油页岩的有机岩石学特征与生、排烃意义[J]. 沉积学报, 2006, 24(1): 113-122.
引用本文: |
曾庆辉. 富有机质的黑色页岩和油页岩的有机岩石学特征与生、排烃意义[J]. 沉积学报, 2006, 24(1): 113-122.
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ZENG Qinghui. Organic Petrological Study on Hydrocarbon Generation and Expulsion from Organicrich Black Shale and Oil Shale[J]. Acta Sedimentologica Sinica, 2006, 24(1): 113-122.
Citation: |
ZENG Qinghui. Organic Petrological Study on Hydrocarbon Generation and Expulsion from Organicrich Black Shale and Oil Shale[J]. Acta Sedimentologica Sinica, 2006, 24(1): 113-122.
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