Abstract
There are great differences in biomarks between Cambrian oil and Middle-Upper Ordovician oil. In this stuty, the authors analyzed 40 oils found in Lunnan area by GC-MS and calculated the content of Cambrian oil in the 40 oils according to the steroid indexes of typical oil mixture and match experiment. The results show that it is a general phenomenon in Ordovician reservoir that the oil derived from Cambrian source rock mixed with the oil derived from Middle-Upper Ordovician source rock in Lunnan area, the mixture degree of the two oils is lower in Carboniferous reservoir than in Ordovician reservoir, and the oils kept in Triassic reservoir have single source, Middle-Upper Ordovician source rock. The mixture oils mainly composed of Cambrian oil (>50%) distributed in Sangtamu fault zone, and the oils found in Lunnan fault zone are Middle-Upper Ordovician oil. This distribution of oils in Lunnan area is owing to that Lunnan fault zone is located in anticline axis part, Lunnan fault zone underwent serious erosion, and the oils from Cambrian source rock accumulated in Lunnan fault zone were degraded completely during Caledonian-Hercynian movement. But the Cambrian oil accumulated in Sangtamu fault zone was not degraded completely and some of them were left for the location of Sangtamu fault zone is lower than Lunnan fault zone. Later, the oil derived from Middle-Upper Ordovician source rock mixed with the remained Cambrian oil, and the mixture oil formed in Sangtamu fault zone.
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References
Jia C Z. Structure and Oil & Gas in the Tarim Bsain, China (in Chinese). Beijing: Petroleum Industrial Press, 1997
Huang D F, Liu B W, Wang T D, et al. Genetic type and maturity of lower Paleozoic marine hydrocarbon gases in the eastern Tarim Basin. Chem Geol (in Chinese), 1999, 162: 65–77
Xiao X M, Liu D H, Fu J M, et al. Multiple phases of hydrocarbon generation and migration in the Tazhong of the Tarim Basin, People’s Republic of China. Org Geochem, 1996, 25: 191–197
Lu X X, Jin Z J, Liu L F, et al. Oil and gas accumulations in the Ordovician carbonates in the Tazhong Uplift of the Tarim Basin, west China. Petrol Sci Eng (in Chinese), 2004, 41: 109–121
Zhang S C, Liang D G, Zhang B M, et al. The Formation of Marine Oil and Gas in the Tarim Basin (in Chinese). Beijing: Petroleum Industrial Press, 2005. 254–260
Hanson A D, Zhang S C, Moldowan J M. Molecular organic geochemistry of Tarim Basin, Northwest China. AAPG Bull, 2000, 84: 1109–1128
Zhang S C, Huang H P. Geochemistry of Palaeozoic marine petroleum from the Tarim Basin, NW China: Part 1. Oil family classification. Org Geochem, 2005, 36: 1204–1214
Yang J, Huang H P, Zhang S C, et al. Semi-quantitative evaluation of mixed oil in northern uplift of the Tarim Basin. Geochimica (in Chinese), 2003, 32(2): 105–111
Wang T G, Wang C J, He F Q, et al. Determination of double filling ratio of mixed crude oils in the Ordovcian reservoir, TaHe oil field. Petrol Geol Exp (in Chinese), 2004, 26(1): 74–79
Zhang S C, Liang D G, Li M W. Molecular fossils and the oil-source rock correlations in the Tarim Basin, NW China. Chin Sci Bull (in Chinese), 2002, 47(Suppl): 20–27
Zhang S C, Moldowan J M, Li M W, et al. The abnormal distribution of the molecular fossils in the pre-Cambrian and Cambrian: Its biological significance. Sci China Ser D-Earth Sci, 2002, 45(3): 193–200
Zhang S C, Wang F Y, Zhang B M, et al. Middle-upper Ordovician source rock geochemistry of Tarim Basin. Acta Petrol Sin (in Chinese), 2000, 21(6): 23–28
Mi J K, Zhang S C, Tu J Q, et al. Study on the formation of the Hadexun oilfield in Tarim Basin, NW China. Geochimica (in Chinese), 2006, 35(4): 405–412
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Supported by the National Key Basic Research and Development Program of China (Grant No. 2006CB202307)
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Mi, J., Zhang, S., Chen, J. et al. The distribution of the oil derived from Cambrian source rocks in Lunnan area, the Tarim Basin, China. Chin. Sci. Bull. 52 (Suppl 1), 133–140 (2007). https://doi.org/10.1007/s11434-007-6004-x
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DOI: https://doi.org/10.1007/s11434-007-6004-x