The distribution characteristic and its significance of compound specific isotopic composition of aromatic hydrocarbon from marine source rock and oil in the Tarim Basin, western China

Science China Earth Sciences - Tập 57 - Trang 2791-2798 - 2014
Min Zhang1,2, HongJing Zhao1,2, YanChun Hong3, ZuLin Chen1,2, JunFeng Lin2
1The Key Laboratory of Exploration Technologies for Oil and Gas Resources, Ministry of Education, Yangtze University, Wuhan, China
2School of Earth Environment and Water Resources, Yangtze University, Wuhan, China
3CNPC International (PK) Co. Ltd., Beijing, China

Tóm tắt

Aromatic hydrocarbons are generally main distillation of crude oil and organic extract of source rocks. Bicyclic and tricyclic aromatic hydrocarbons can be purified by two-step method of chromatography on alumina. Carbon isotopic composition of individual aromatic hydrocarbons is affected not only by thermal maturity, but also by organic matter input, depositional environment, and hydrocarbon generation process based on the GC-IRMS analysis of Upper Ordovician, Lower Ordovician, and Cambrian source rocks in different areas in the Tarim Basin, western China. The subgroups of aromatic hydrocarbons as well as individual aromatic compound, such as 1-MP, 9-MP, and 2,6-DMP from Cambrian-Lower Ordovician section show more depleted 13C distribution. The δ13C value difference between Cambrian-Lower Ordovician section and Upper Ordovician source rocks is up to 16.1‰ for subgroups and 14‰ for individual compounds. It can provide strong evidence for oil sourc correlation by combing the δ13C value and biomarker distribution of different oil and source rocks from different strata in the Tarim Basin. Most oils from Tazhong area have geochemical characteristics such as more negative δ13C9-MP value, poor gammacerane, and abundant homohopanes, which indicate that Upper Ordovician source rock is the main source rock. In contrast, oils from Tadong area and some oils from Tazhong area have geochemical characteristics such as high δ13C9-MP value, abundant gammacerane, and poor homohopanes, which suggest that the major contributor is Cambrian-Lower Ordovician source rock.

Tài liệu tham khảo

Chen Z L, Zhang M, Liu H Y. 2013. Micro-column convenient chromatography for separation of aromatic hydrocarbon compound and GC / IRMS analysis (in Chinese). Petrol Geol Exp, 35: 1–4 Chen Z L, Zhao H J, Zhang M, et al. 2012. Rapid separation and enrichment of alkylated naphthalenes and alkylated phenanthrenes in crude oils by small-sized alumina column chromatography (in Chinese). J Oil Gas Tech, 34: 34–39 Freeman K H, Boreham C J, Summons R E, et al. 1994. The effect of aromatization on the isotopic compositions of hydrocarbons during early diagenesis. Org Geochem, 21: 1037–1049 Grice K, Nabbefeld B, Maslen E. 2007. Source and significance of selected polycyclic aromatic hydrocarbons in sediments (Hovea-3 well, Perth Basin, Western Australia) spanning the Permian-Triassic boundary. Org Geochem, 38: 1795–1803 Jia W L, Peng P A, Xiao Z Y. 2008. Carbon isotopic compositions of 1,2,3, 4-tetramethylbenzene in marine oil asphaltenes from The Tarim Basin: Evidence for the source formed in a strongly reducing environment. Sci China Ser D-Earth Sci, 51: 509–514 Jin Z J. 2006. New progresses in research of China’s typical superimposed basins and reservoiring of hydrocarbons (PartII): Taking The Tarim Basin as an example (in Chinese). Oil Gas Geol, 27: 281–288 Kim M, Kennicutt M C, Qian Y. 2005. Polycyclic aromatic hydrocarbon purification procedures for compound specific isotope analysis. Environ Sci Technol, 39: 6770–6776 Lin J F, Zhang M. 2011. Research advance of molecular isotope of aromatic hydrocarbons in fossil fuel (in Chinese). J Oil Gas Technol, 33: 24–29 Liu M M, Ling Y, Xie M M, et al. 2010. Advances in compound specific isotope analysis of polycyclic aromatic hydrocarbons (in Chinese). Rock Miner Anal, 29: 64–70 Maslen E, Grice K, Le Métayer P, et al. 2011. Stable carbon isotopic compositions of individual aromatic hydrocarbons as source and age indicators in oils from western Australian basins. Org Geochem, 42: 387–398 Peters K, Walters C, Moldowan J, 2005. The Biomarker Guide. Vol. 1: Biomarkers and Isotopes in the Environment and Human History. Cambridge: Cambridge University Press Radke M, Hilkert A, Rullkötter J. 1998. Molecular stable carbon isotope compositions of alkylphenanthrenes in coals and marine shales related to source and maturity. Org Geochem, 28: 785–795 Sofer Z, Zumberge J E, Lay V. 1986. Stable carbon isotopes and biomarkers as tools in understanding genetic relationship, maturation, biodegradation, and migration of crude oils in the Northern Peruvian Oriente (Maranon) Basin. Org Geochem, 10: 377–389 Wang Z M, Xiao Z. 2004. A comprehensive review concerning the problem of marine crudes sources in the Tarim Basin. Chin Sci Bull, 49: 1–9 Zhang M, Huang G H, Hu G Y. 2006. Reservoir geochemistry of the Tazhong oilfield in the the Tarim Basin, China, Part I. Geochemistry characteristics and genetic classification of crude oils. Chin J Geochem, 25: 157–162 Zhang S C, Hanson A D, Moldowan J M, et al. 2000. Paleozoic oil-source rock correlations in the Tarim Basin, NW China. Org Geochem, 31: 273–286 Zhou P Y, Sun Y G. 2008. Rapid separation of alkylated naphthalenes in crude oils by column chromatography and its elementary application (in Chinese). Geochimica, 37: 512–518 Zhu G Y, Cui J, Yang H J, et al. 2011. The distribution and origin of Cambrian crude oil in North Tarim Basin (in Chinese). Acta Petrol Sin, 27: 2435–2446