Characteristics of Hydrocarbon Generation Potential, Hydrocarbon Composition and Hydrocarbon Generating model of Desmocollinite from Late Permian Coals in Shuicheng, Guizhou Province
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摘要: 基质镜质体是华南晚二叠世煤中的主要组分之一,其在煤中含量的多少、生烃潜力的大小、生烃特性等直接影响到该区煤成油气资源的评价。采用岩石热解、热解气相色谱以及开放体系下热模拟等方法,对贵州水城晚二叠世(P21)龙潭组煤中基质镜质体的生烃潜力、烃类组成特征、生烃模式进行了研究。结果表明:本区基质镜质体的生烃潜力、氢指数分别为191.99mg/g和250mg/gTOC,远高于丝质体的生烃潜力(26.17mg/g)和氢指数(35mg/gTOC),而小于树皮体的生烃潜力(297mg/g)和氢指数(491mg/gTOC);基质镜质体热解烃类组成中以轻质烃为主,湿气次之,可见本区基质镜质体不但能生成气态烃,而且能生成一定量的液态烃,这归因于其中所含大量的超微类脂体;基质镜质体“生油窗”温度范围为375~475℃,主要生烃温度区间为400~450℃,其中415~430℃为生烃高峰期,420℃处产烃率最高。基质镜质体这种在高成熟度下(大于VRo1.0%)大量生烃的特点对在成熟度普遍较高的华南地区寻找油气田具有重要的意义。Abstract: Desmocollinite is one of the major macerals of Late Permian Longtan Formation coals in Shuicheng, Guizhou Province, Southwest China. The characteristics of hydrocarbon generation of desmocollinite are important to evaluate and explore oil and gas resources derive from coals. In this paper, Rock eval, Py GC and experimental simulation in an open system were used to study hydrocarbon generation potential, hydrocarbon composition, hydrocarbon generation model and thermoevolutional characteristics of desmocollinite. The results indicate that desmocollinite has high hydrocarbon generation potential, with (S 1+S 2) of 191.6mg/g, which is higher than that of fusinite (S 1+S 2 is 26.2mg/g,), and lower than of barkinite (S 1+S 2 is 297mg/g); light hydrocarbon (C 6-C 14 )and wet gas (C 2-C 5)are the main hydrocarbon composition; the "oil window" of desmocollinite is within 375~475 ℃, the main temperature range of hydrocarbon generation is at 400~450 ℃ with a peak range of 410~430 ℃, and the temperature of maximum hydrocarbon generating rates is at 420 ℃. These studies show that desmocollinite from barkinite rich coal is one of oil generated macerals, which is attributed to abundant submicro liptinites in desmocollinite,and desmocollinite also can generate a large amount of hydrocarbon in higher mature degree, these hydrocarbon generating model of desmocollinite is favorable for exploring oil and gas resources in South China.
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[1] 孙旭光,秦胜飞,金奎励.贵州水城晚二叠世含树皮体煤成烃特性研究[J].地球化学,28(6):605~611 [2] Bertrand. Geochemical and petrographic characterization of humic coals considered as possible oils source rocks[J]. Org. Geochem., 1984, 6: 481 ~488 [3] Mukhopadhyay P K, Gormly J R, Zumbcrge J E. Generation of hydrocarbons from the Tertiary coals of Texas - Coals as potential source rock for liquid hydrocarbons in a detaic basin[J]. Organic Geochemistry, 1989, 14: 351~362. [4] Mukhopadhyay P K, Gormly J R. Hydrocarbon potential of two types of resinite, In: Schenck P A,etal. eds, Advances in Organic Geochemistry[C]. Perganon, Press, Oxford, 1984. 439~454 [5] Smith G C, Cook A C. Petroleum occurrence in the Gippsland Basin and its relation to rank and organic natter type[J]. APEA J., 1984, 24: 196~216 [6] Taylor G H, I iu S Y, Smith M. New light on the origin of Cooper basin oil[J]. APEA Journal, 1988, 28:303~309 [7] Taylor G H. The electron microscopy of vitrinites coal sciences [C]. Adv. Chem. Scr., 1966, 55:274~283 [8] Taylor G H, Teichmuller M. Observation on fluorinite and fluorescent vitrinite with the transnission electron microscope[J]. Inter. J. Coal Geol., 1992, 22:61~82 [9] 赵师庆,王飞宇,刘德汉等.不同煤相煤和镜质组产烃性质的研究[A].中国科学院地球化学研究所有机地球化学开放室年报(1988)[C]北京:科学出版社,1990.128~137 [10] 王飞宇,傅家谟,刘德汉.煤和烃源岩镜质体中超微类质体检出及意义[J]科学通报,1993,38(2):151~154 [11] 于冰,张井,王大庆.富氢镜质体超微结构与生油潜力的TEM研究[J].中国矿业大学学报,1998,27(1):95~98 [12] 赵长毅,金奎励等.吐哈盆地煤中基质镜质体生烃潜力与特征[J]科学通报,1994,39(21):1979~1981 [13] 赵长毅,程克明,王飞宇.吐哈盆地煤成烃主要贡献组分剖析[J].沉积学报,1997,15(2):95~99 [14] 赵长毅,程克明.吐哈盆地煤及显微组分生烃模式[J].科学通报,1997,42(19):2102~2105 [15] 程克明.吐哈盆地油气生成[M]北京:石油工业出版社,1994.5~84 [16] 刘德汉.吐哈盆地及二连盆地侏罗系煤微类脂组分的共聚焦激光扫描显微镜(CLSM)研究及油气意义[J].地球化学,1996,25(4):309~329 [17] 秦匡宗,郭绍辉,黄第藩等.煤岩显微组分的化学结构与成烃潜力[J].石油大学学报.1995,19(4):87~94 [18] Xie K C, Zheng Y F, Li C Z et al. Pyrolysis characteristics of macerals separated from a single coal and their artificial mixture[J]. Fuel, 1991, 70:474~479 [19] 孙旭光,李荣西,杜美利.煤显微组分分离富集[J].中国煤田地质,1997,9(3):26~27
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