Method and application of hydrogen isotope analysis of n-alkanes
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摘要: 以渤海湾盆地东营凹陷古近系沙河街组烃源岩及原油为研究对象,通过气相色谱仪—GC/TC接口—同位素质谱仪的联用,构建了正构烷烃单体烃氢同位素在线分析方法,对正构烷烃的单体烃氢同位素组成进行了测定,揭示了不同沉积环境中氢同位素的组成特征。沙四上亚段烃源岩的正构烷烃单体烃氢同位素组成较重,分布于-161‰~-111‰,沙三下亚段烃源岩的氢同位素组成较轻,分布在-186‰~-134‰,指示了从微咸水到咸水的沉积环境,随着沉积环境水体盐度的增加,氢同位素值具有明显变重的趋势,成熟度差异较大的样品,其氢同位素组成的差异相对较小。表明在正常生油窗范围内,正构烷烃单体烃的氢同位素受成熟度影响相对较小,主要与母质来源和沉积环境有关,可为油源对比、母质来源和古沉积环境判识提供科学依据。Abstract: The source rock and crude oil from the Shahejie Formation in the Dongying Sag of the Bohai Bay Basin were studied. Hydrogen isotopic compositions of n-alkanes from different sedimentary environments were determined using a combination of gas chromatograph, GC/TC interface and an isotope mass spectrometer. In the upper section of the fourth member of Shahejie Formation, the hydrogen isotopic composition of source rocks was heavy, ranging from -161‰ to -111‰. While the hydrogen isotopic composition of source rocks in the lower section of the third member of Shahejie Formation was relatively lighter, ranging from -186‰ to -134‰. The results suggested that from brackish water to saline water sedimentary environment, the hydrogen isotope value shifted toward heavier composition following the increasing of salinity in water. The difference of hydrogen isotopic composition was relatively smaller for samples with large maturity differences. The results indicated that the influence of maturity on hydrogen isotopes of a single hydrocarbon was relatively smaller in the range of the normal oil generation window, which was mainly related to the source of parent material and the sedimentary environment. The characteristics of hydrogen isotopic composition of n-alkanes could provide an important scientific basis for the correlation of oil and source rock and the identification of parent material source and paleosedimentary environment.
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Key words:
- n-alkanes /
- hydrogen isotope /
- oil-source rock correlation /
- Dongying Say /
- Bohai Bay Basin
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表 1 渤海湾盆地东营凹陷烃源岩和原油样品数据
Table 1. Source rock and crude oil sample data, Dongying Sag, Bohai Bay Basin
井号 井段/m 层位 样品性质 有机碳含量/% 氯仿沥青“A”/% (S1+S2)/(mg·g-1) T73 3 376.5 Es4上 灰色泥岩 2.66 0.545 7 14.45 F112 3 430.6 Es4上 纹层泥岩 3.43 0.902 0 24.44 H130 3 220.4 Es3下 深灰色泥岩 2.95 0.685 7 18.18 S121 3 564.8 Es3中 深灰色泥岩 2.58 0.496 7 15.19 L49-11 2 957.0 Es3中 深灰色泥岩 2.50 0.326 4 13.56 C41-3 3 067.3 Es4上 原油 C6-31 2 836.0 Es4上 原油 L38-22 2 273.0 Es3中 原油 L53 2 761.8 Es3中 原油 表 2 渤海湾盆地东营凹陷烃源岩生物标志物数据
Table 2. Biomarker data of source rocks, Dongying Sag, Bohai Bay Basin
井名 CPI OEP Pr/Ph Pr/nC17 Ph/nC18 Ts/(Ts+Tm) 甾烷 伽马蜡烷/C30 C29S/(S+R) C29ββ/(ββ+αα) C27 C28 C29 T73 1.02 0.98 0.42 0.96 2.05 0.70 41 21 38 1.52 0.46 0.55 F112 1.03 1.01 0.46 0.65 1.42 0.47 30 22 48 0.32 0.48 0.41 H130 1.10 1.09 1.02 0.61 0.59 0.48 44 24 32 0.09 0.51 0.44 S121 1.17 1.16 1.25 0.42 0.32 0.52 46 23 31 0.05 0.42 0.51 L49-11 1.77 1.64 1.95 0.64 0.40 0.39 49 21 29 0.05 0.25 0.27 表 3 渤海湾盆地东营凹陷原油生物标志物数据
Table 3. Biomarker data of crude oil, Dongying Sag, Bohai Bay Basin
井名 CPI OEP Pr/Ph Pr/nC17 Ph/nC18 Ts/(Ts+Tm) 甾烷 伽马蜡烷/C30 C29S/(S+R) C29ββ/(ββ+αα) C27 C28 C29 C41-3 1.01 1.00 0.40 0.94 2.08 0.40 41 23 36 0.37 0.44 0.39 C6-31 1.02 1.02 0.51 0.70 1.39 0.43 39 26 34 0.37 0.33 0.32 L38-22 1.11 1.12 0.88 0.57 0.70 0.42 43 23 34 0.12 0.37 0.38 L53 1.10 1.11 1.21 0.40 0.35 0.60 45 22 33 0.07 0.44 0.56 -
[1] 沈平, 徐永昌. 石油碳、氢同位素组成的研究[J]. 沉积学报, 1998, 16(4): 124-127. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB804.020.htmSHEN Ping, XU Yongchang. Study on carbon and hydrogen isotopes composition of crude oils[J]. Acta Sedimentologica Sinica, 1998, 16(4): 124-127. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB804.020.htm [2] 戴金星, 裴锡古, 戚厚发. 中国天然气地质学(卷一)[M]. 北京: 石油工业出版社, 1992: 1-149.DAI Jinxing, PEI Xigu, QI Houfa. The geology of natural gas in China (Volume 1)[M]. Beijing: Petroleum Industry Press, 1992: 1-149. [3] 刘文汇, 王晓锋, 腾格尔, 等. 中国近十年天然气示踪地球化学研究进展[J]. 矿物岩石地球化学通报, 2013, 32(3): 279-289. https://www.cnki.com.cn/Article/CJFDTOTAL-KYDH201303001.htmLIU Wenhui, WANG Xiaofeng, TENGER, et al. Research progress of gas geochemistry during the past decade in China[J]. Bulletin of Mineralogy Petrology and Geochemistry, 2013, 32(3): 279-289. https://www.cnki.com.cn/Article/CJFDTOTAL-KYDH201303001.htm [4] 陶成, 把立强, 王杰, 等. 天然气氢同位素分析及应用[J]. 石油实验地质, 2008, 30(1): 94-97. doi: 10.11781/sysydz200801094TAO Cheng, BA Liqiang, WANG Jie, et al. Analysis and application of hydrogen isotopic composition of the natural gas[J]. Petroleum Geology & Experiment, 2008, 30(1): 94-97. doi: 10.11781/sysydz200801094 [5] SCHOELL M. Recent advances in petroleum isotope geochemistry[J]. Organic Geochemistry, 1984, 6: 645-663. doi: 10.1016/0146-6380(84)90086-X [6] 李洪波. 塔北隆起北缘原油轻烃单体烃碳同位素特征[J]. 石油实验地质, 2013, 35(3): 302-306. doi: 10.11781/sysydz201303302LI Hongbo. Compound specific carbon isotope composition of light hydrocarbons in crude oils from the north of the Northern Tarim Uplift[J]. Petroleum Geology & Experiment, 2013, 35(3): 302-306. doi: 10.11781/sysydz201303302 [7] 张林晔, 刘庆, 张春荣. 东营凹陷成烃与成藏关系研究[M]. 北京: 地质出版社, 2005.ZHANG Linye, LIU Qing, ZHANG Chunrong. Study on the genetic relationships between hydrocarbon occurrence and pools formation in Dongying Depression[M]. Beijing: Geological Publishing House, 2005. [8] 张顺, 刘惠民, 王永诗, 等. 东营凹陷古近系页岩成岩事件及其对页岩储集空间发育特征的影响[J]. 油气地质与采收率, 2019, 26(1): 109-118. https://www.cnki.com.cn/Article/CJFDTOTAL-YQCS201901012.htmZHANG Shun, LIU Huimin, WANG Yongshi, et al. Diagenetic event of Paleogene shale and its influence on development characteristics of shale pore space in Dongying Sag[J]. Petroleum Geo-logy and Recovery Efficiency, 2019, 26(1): 109-118. https://www.cnki.com.cn/Article/CJFDTOTAL-YQCS201901012.htm [9] 陈祖林, 张敏, 刘海钰. 芳烃单体烃GC/IRMS分析分离的便捷柱色谱法[J]. 石油实验地质, 2013, 35(3): 347-350. doi: 10.11781/sysydz201303347CHEN Zulin, ZHANG Min, LIU Haiyu. Micro-column convenient chromatography for separation of aromatic hydrocarbon compound and GC/IRMS analysis[J]. Petroleum Geology & Experiment, 2013, 35(3): 347-350. doi: 10.11781/sysydz201303347 [10] 曹蕴宁, 刘卫国. 气相色谱-热转换-同位素比值质谱法测定单体氢同位素稳定性的影响因素分析[J]. 质谱学报, 2018, 39(6): 670-678. https://www.cnki.com.cn/Article/CJFDTOTAL-ZPXB201806004.htmCAO Yunning, LIU Weiguo. Factors affecting the stability of hydrogen isotopes measurements by gas chromatography-thermal conversion-isotope ratio mass spectrometry[J]. Journal of Chinese Mass Spectrometry Society, 2018, 39(6): 670-678. https://www.cnki.com.cn/Article/CJFDTOTAL-ZPXB201806004.htm [11] 郝小娟, 谈树苹, 赵立飞. 氢同位素气体在线分析装置研制及分析方法建立[J]. 化学分析计量, 2018, 27(3): 108-112. https://www.cnki.com.cn/Article/CJFDTOTAL-HXFJ201803060.htmHAO Xiaojuan, TAN Shuping, ZHAO Lifei. Development of on-line analysis device for hydrogen isotope gas and analysis method establishment[J]. Chemical Analysis and Meterage, 2018, 27(3): 108-112. https://www.cnki.com.cn/Article/CJFDTOTAL-HXFJ201803060.htm [12] 陈莎莎, 朱信旭, 贾望鲁, 等. 用于单体氢同位素分析的混合溶剂洗脱5Å分子筛吸附正构烷烃的方法[J]. 岩矿测试, 2017, 36(4): 413-419. https://www.cnki.com.cn/Article/CJFDTOTAL-YKCS201704011.htmCHEN Shasha, ZHU Xinxu, JIA Wanglu, et al. Elution of adsorbed n-alkanes by 5Å molecular sieve using solvent mixtures for compound-specific hydrogen isotopic analysis[J]. Rock and Mineral Analysis, 2017, 36(4): 413-419. https://www.cnki.com.cn/Article/CJFDTOTAL-YKCS201704011.htm [13] 张文龙, 黄凌. 天然气中烃类单体化合物氢同位素分析涂炭方法优化[J]. 石油实验地质, 2018, 40(6): 855-858. doi: 10.11781/sysydz201806855ZHANG Wenlong, HUANG Ling. Optimization of compound-specific hydrogen isotope analysis of natural gas[J]. Petroleum Geology & Experiment, 2018, 40(6): 855-858. doi: 10.11781/sysydz201806855 [14] 黄雪峰, 吴伟. 辽中凹陷古近系烃源岩生烃模拟[J]. 油气藏评价与开发, 2017, 7(1): 1-6. https://www.cnki.com.cn/Article/CJFDTOTAL-KTDQ201701001.htmHUANG Xuefeng, WU Wei. Hydrocarbon generating simulation of Paleogene source rocks in Liaozhong Sag[J]. Reservoir Evaluation and Development, 2017, 7(1): 1-6. https://www.cnki.com.cn/Article/CJFDTOTAL-KTDQ201701001.htm [15] 潘银华, 黎茂稳, 孙永革, 等. 江汉盆地潜江凹陷盐间云质页岩热压生排烃模拟实验研究[J]. 石油实验地质, 2018, 40(4): 551-558. doi: 10.11781/sysydz201804551PAN Yinhua, LI Maowen, SUN Yongge, et al. Thermo-compression simulation of hydrocarbon generation and expulsion of inter-salt dolomitic shale, Qianjiang Sag, Jianghan Basin[J]. Petroleum Geology & Experiment, 2018, 40(4): 551-558. doi: 10.11781/sysydz201804551 [16] 郑见超, 李斌, 刘羿伶, 等. 塔里木盆地下寒武统玉尔吐斯组烃源岩热演化模拟分析[J]. 油气藏评价与开发, 2018, 8(6): 7-12 https://www.cnki.com.cn/Article/CJFDTOTAL-KTDQ201806002.htmZHENG Jianchao, LI Bin, LIU Yiling, et al. Study on thermal evolution modeling of Lower Cambrian Yuertusi source rock, Tarim Basin[J]. Reservoir Evaluation and Development, 2018, 8(6): 7-12. https://www.cnki.com.cn/Article/CJFDTOTAL-KTDQ201806002.htm [17] 陆燕, 王小云, 曹建平. 沉积物中16种多环芳烃单体碳同位素GC-C-IRMS测定[J]. 石油实验地质, 2018, 40(4): 532-537. doi: 10.11781/sysydz201804532LU Yan, WANG Xiaoyun, CAO Jianping. Compound-specific carbon stable isotope analysis of 16 polycyclic aromatic hydrocarbons in sediments by Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry (GC-C-IRMS)[J]. Petroleum Geology & Experiment, 2018, 40(4): 532-537. doi: 10.11781/sysydz201804532 [18] 段毅, 姚泾利, 吴应忠, 等. 低纬度淡水湖沉积物中正构烷烃氢同位素组成特征及其有机质源和环境指示意义[J]. 地质学报, 2017, 91(8): 1894-1904. https://www.cnki.com.cn/Article/CJFDTOTAL-DZXE201708016.htmDUAN Yi, YAO Jingli, WU Yingzhong, et al. Hydrogen isotopic composition of n-alkanes in sediments from freshwater lake, the low latitude region of China: implications for organic matter source and environment[J]. Acta Geologica Sinica, 2017, 91(8): 1894-1904. https://www.cnki.com.cn/Article/CJFDTOTAL-DZXE201708016.htm [19] 赵悦, 蔡进功, 谢奥博, 等. 淡水和咸水湖相泥质烃源岩不同赋存态有机质的地球化学特征[J]. 石油实验地质, 2018, 40(5): 705-715. doi: 10.11781/sysydz201805705ZHAO Yue, CAI Jingong, XIE Aobo, et al. Geochemical investigation of organic matter of various occurrences released via sequential treatments of two argillaceous source rock samples from fresh and saline lacustrine environments[J]. Petroleum Geology & Experiment, 2018, 40(5): 705-715. doi: 10.11781/sysydz201805705 [20] 熊永强, 耿安松, 潘长春, 等. 陆相有机质中单体烃的氢同位素组成特征[J]. 石油勘探与开发, 2004, 33(1): 60-63. https://www.cnki.com.cn/Article/CJFDTOTAL-SKYK200401018.htmXIONG Yongqiang, GENG Ansong, PAN Changchun, et al. Hydrogen isotopic compositions of individual n-alkanes in terrestrial source rocks[J]. Petroleum Exploration and Development, 2004, 33(1): 60-63. https://www.cnki.com.cn/Article/CJFDTOTAL-SKYK200401018.htm [21] 宋振响, 周世新, 穆亚蓬, 等. 正构烷烃分布模式判断柴西主力烃源岩[J]. 石油实验地质, 2011, 33(2): 182-187. doi: 10.11781/sysydz201102182SONG Zhenxiang, ZHOU Shixin, MU Yapeng, et al. Identification of chief hydrocarbon source rocks based on n-alkane distribution patterns in western Qaidam Basin[J]. Petroleum Geology & Experiment, 2011, 33(2): 182-187. doi: 10.11781/sysydz201102182 [22] LLOYD R M. Oxygen isotope enrichment of sea water by evaporation[J]. Geochimica et Cosmochimica Acta, 1966, 30(8): 801-814. [23] SOFER Z, GAT J R. The isotope composition of evaporating brines: effect of the isotopic activity ratio in saline solutions[J]. Earth and Planetary Science Letters, 1975, 26(2): 179-186. [24] LI Maowen, HUANG Yongsong, OBERMAJER M, et al. Hydrogen isotopic compositions of individual alkanes as a new approach to petroleum correlation: case studies from the Western Canada Sedimentary Basin[J]. Organic Geochemistry, 2001, 32(12): 1387-1399. [25] 卢鸿, 李超, 肖中尧, 等. 轮南油田代表性原油正构烷烃单体氢同位素组成、分布与母源信息[J]. 中国科学(D辑地球科学), 2004, 34(12): 1145~1150. https://www.cnki.com.cn/Article/CJFDTOTAL-JDXK200412006.htmLU Hong, LI Chao, XIAO Zhongyao, et al. Hydrogen isotopic compositions, distributions and source signals of individual n-alkanes for some typical crude oils in Lunnan Oilfield[J]. Science In China(Ser. D Earth Sciences), 2004, 34(12): 1145-1150. https://www.cnki.com.cn/Article/CJFDTOTAL-JDXK200412006.htm