GEOCHEMICAL CHARACTERISTICS AND SOURCE OF PALEO- RESERVOIR SOLID BITUMEN IN SHIWANDASHAN BASIN
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摘要: 根据沥青产状、族组成、饱和烃色谱、生物标志化合物、碳同位素以及沥青热演化程度等,对广西十万大山盆地北缘的老虎山古油藏、上屯古油藏二叠系灰岩中固体沥青的地球化学特征进行了系统分析,并结合有关烃源岩地球化学特征及油气成藏研究成果对其来源和成因进行了探讨.结果表明,古油藏沥青抽提物含量低,族组成中芳烃和非烃含量高,饱和烃含量低,芳烃含量最高可达58.60%.饱和烃气相色谱分析表明,沥青具还原环境、以低等水生生源为主的母质来源及较高的热演化程度.沥青稳定碳同位素为-27.8‰~-28.7‰,反映其生烃母质以低等生源为主.沥青中的甾、萜烷含量很低,且以低分子量化合物占绝对优势,其中甾烷系列中具很高的孕甾烷含量,萜烷则以三环萜烷为主,反映其高热演化特征.沥青几乎不含芳香甾烷,与本区上二叠统泥质烃源岩特征相似;沥青反射率为1.9%~2.5%,结合本区生烃成藏演化史分析结果,反映其经历过230℃高温.最后结合相关烃源岩地球化学特征及有关油气成藏信息,综合认为古油藏沥青与上二叠统泥质烃源岩有较好的亲缘关系,是古油藏早期原油高温裂解的产物之一,即焦沥青.Abstract: Systematic geochemical analysis such as bitumen occurrence,group composition of dissolved organic matter,saturated hydrocarbon chromatography,biomarker compounds,carbon isotope and bitumen thermal maturation is applied to the solid bitumen of Laohushan and Shangtun paleo-reservoirs from Permian limestones in Shiwandashan Basin of Guangxi Province,China.And combined with geochemical characters of hydrocarbon source rocks and reservoir-forming mechanism,the source and genesis of above two solid bitumen has been discussed.The results show that the content of dissolved organic matter and saturated hydrocarbon is very poor and the content of aromatic hydrocarbon(the highest being 58.60%)and nonhydrocarbon is rich.The gas chromatogram analysis of saturated hydrocarbon show that bitumen is from reduction environment originating from lower grade aquatic geology with higher thermal evolution degree.The stable carbon isotope of bitumen is -27.8‰~-28.7‰,reflecting that the main source of input of source rock is lower aquatic biology.The lower content of sterane and terpane(dominated by low molecular compounds),higher content of pregnane in sterane series and tricyclic terpane predominated in terpane indicate that the bitumen was characterised by high evolution.Like the argillaceous source rock of Permian,there is nearly no aromatic sterane in bitumen.The reflectance of bitumen is 1.9%~2.5%,and the equivalent vitrinite reflectance is 1.6%~2.0%,associated with the results of reservoiring and evolution history,it shows that the bitumen experienced 230℃ temperature.Finally combined with relative geochemical characters of hydrocarbon and certain information of reservoir-forming,it is considered that the paleo-reservoir bitumen has closer genetic relationship with Upper Permian argillaceous source rock,and it is one of the final pyrolysis products of crude oil in paleo-reservoir,(that is pyrobitumen).
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Key words:
- paleo-reservoir /
- reservoir bitumen /
- geochemical characteristics /
- bitumen source /
- bitumen genesis /
- aromatic sterane
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[1] 肖贤明,刘德汉,傅家谟.沥青反射率作为烃源岩成熟度指标的意义[J].沉积学报,1991,9(S1):138-146 [2] 肖贤明,刘德汉,傅家谟等.应用沥青反射率推算油气生成与运移的地质时间[J].科学通报,2000,45(19):2123-2127 [3] 崔会英,张莉.四川盆地威远-资阳地区震旦系储层沥青特征及意义[J].石油实验地质,2008,30(5):489-493 [4] 王建宝,肖贤明,郭汝泰.四川盆地早古生代地层中沥青的成因及其生气潜力研究[J].天然气工业,2003,23(5):127-129 [5] 赵孟军,张水昌,赵陵等.南盘江盆地油气成藏过程及天然气勘探前景分析[J].地质论评,2006,52(5):642-649 [6] 赵孟军,张水昌,赵陵等.南盘江盆地古油藏沥青地球化学特征及成因[J].地质学报,2006,80(6):893-902 [7] 赵孟军,张水昌,赵陵等.南盘江盆地古油藏沥青、天然气的地球化学特征及成因[J].中国科学D辑:地球科学,2007,37(2):167-177 [8] 饶丹,秦建中.川西北广元地区海相层系油苗和沥青来源分析[J].石油实验地质,2008,30(6):596-599,605 [9] 高志农,胡华中.高压对天然沥青结构组成演变的影响[J].沉积学报,2002,20(3):499-504 [10] 李艳霞,钟宁宁.川东石炭系气藏中固体沥青形成机理探讨[J].石油实验地质,2007,29(4):402-404 [11] 刘德汉,史继扬.高演化碳酸盐烃源岩非常规评价方法探讨[J].石油勘探与开发,1994,21(3):113-115 [12] 杨永才,张枝焕,常象春等.塔里木盆地YN2井储层沥青的地球化学特征及成因分析[J].矿物岩石,2006,26(2):92-96 [13] 秦胜飞,潘文庆,韩剑发等.储层沥青与有机包裹体生物标志物分析方法[J].石油实验地质,2007,29(3):315-318 [14] 张渠,腾格尔,张志荣等.凯里-麻江地区油苗与固体沥青的油源分析[J].地质学报,2007,81(8):1118-1124 [15] 徐汉林,杨以宁,沈扬等.广西十万大山盆地构造特征新认识[J].地质科学,2001,36 (3):359-363 [16] 郑俊章,陈焕疆.十万大山盆地演化的动力学[J].地学前缘,1995,2(3-4):245-247 [17] 周明辉,麻建明,郑冰.滇黔桂海相油气成藏条件及勘探潜力分析[J].石油实验地质,2005,27(4):333-337 [18] 尹福光,许效松,万方.广西十万大山盆地演化过程及油气资源响应[J].沉积与特提斯地质,2002,22(3):31-35 [19] 周祖翼,郭彤楼,许长海等.广西十万大山盆地中生代地层的裂变径迹研究及其地质意义[J].地质学报,2005,79(3):395-401 [20] 蔡勋育,朱扬明,黄仁春.普光气田沥青地球化学特征及成因[J].石油与天然气地质,2006,27(3):340-347 [21] 赵孟军,张水昌,刘丰忠.油藏演化的两个极端过程[J].石油勘探与开发,2003,30(5):21-23 [22] 梁狄刚,张水昌,张宝民等.从塔里木盆地看中国海相生油问题[J].地学前缘,2000,7 (4):534-547 [23] 张水昌,梁狄刚,张大江等.关于古生界烃源岩有机质丰度的评价标准[J].石油勘探与开发,2002,29 (2):8-12 [24] 何中发,边立曾,陈建平等.十万大山盆地晚二叠世、早三叠世烃源岩中铁元素丰度与有机碳丰度相关关系[J].石油勘探与开发,2004,31(1):45-47 [25] Machel H G,Krouse H R,Sassen R.Products and distinguishing criteria of bacterial and thermochemical sulfate reduction[J].Applied Geochemistry,1995,10 (4):373-389 [26] 梁狄刚,陈建平.中国南方高、过成熟区海相油源对比问题[J].石油勘探与开发,2005,32 (2):8-14 [27] 刘长伟,王飞宇,王忠辉等.十万大山盆地烃源岩有机成熟度评价[J].石油勘探与开发,2002,29(6):8-10 [28] Stasiuk L D.The origin of probitumens in Upper Devonian Laduc Formation gas reservoir,Alberta,Canada:an optical and EDS study of oil to gas transformation[J].Marine and Petroleum Geology,1997,14(7/8):915-929 [29] 刘德汉,史继扬.碳酸盐岩高演化有机质的地球化学特征及油气非常规评价方法[J].天然气工业,1994,14 (增刊):62-67
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