A comparative study on the geochemical characteristics of expelled and retained oil from hydrocarbon generation simulation of Australian Tasmanian oil shale Ⅰ: fraction and isotopic compositions
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摘要: 澳大利亚塔斯马尼亚下二叠统油页岩富含有机质,有机质的生物来源相对单一,主要为塔斯马尼亚藻,且成熟度较低,是热模拟实验的理想样品。为研究排出油与滞留油的地球化学特征和热演化特征,对其进行了生排烃模拟实验。结果表明,该油页岩的生油高峰为340℃;各温度点排出油与滞留油的族组分相对含量对比结果显示,以生油高峰温度点340℃为界,饱和烃和芳烃含量在此温度之前随着温度升高而减少,而生油高峰之后,则随着温度升高而增加;非烃与沥青质的含量则与饱和烃、芳烃的变化趋势相反。排出油中的饱和烃含量比滞留油高,滞留油中的芳烃含量明显大于排出油。排出油与滞留油的族组分稳定碳同位素都发生了倒转,芳烃具有最重的同位素,饱和烃和非烃次之,沥青质一般具有最轻的同位素。在整个模拟过程中,滞留油碳同位素皆重于排出油,芳烃碳同位素最为稳定,表明其可能是油源对比的有效指标。如将模拟生烃后高压釜内含滞留烃的页岩作为页岩油系统,热模拟后高压釜内页岩样品的含油饱和指数(OSI)值在生油高峰附近最高,从一定程度上指示成熟度是影响页岩油勘探的重要因素之一。Abstract: Australian Lower Permian Tasmanian oil shale is rich in organic matter with relatively lower maturity, and the bio-precursor of organic matter is dominated by Tasmanite. Thus it is an ideal sample for thermal simulation experiment. In order to study the compositional characteristics and thermal evolution characteristics of expelled and retained oil, artificial simulation experiments were carried out. Results show that the peak temperature for oil generation of Tasmanian oil shale is ~340 ℃. Taking the peak temperature of 340 ℃ as a boundary, the relative content of oil fractions at each temperature showed that, the content of saturated hydrocarbon and aromatic hydrocarbon decreased with the increase of temperature before 340 ℃, but increased with the increase of temperature after the peak point. The content of polar fraction and asphaltene is opposite to that of saturated aromatic fractions. The content of saturated hydrocarbon in expelled oil is higher than that in retained oil, and the content of aromatic hydrocarbon in retained oil is obviously higher than that in expelled oil. Stable carbon isotopes of the fractions of both expelled oil and retained oil have been reversed. Aromatics appeared to have the heaviest isotope, followed by saturated hydrocarbons and non-hydrocarbons. Asphaltenes generally have the lightest isotopic values. In the whole simulation process, the carbon isotope composition of retained oil is heavier than that of expelled oil, and the aromatic carbon isotope is the most stable, indicating that it is an effective indicator of oil source comparison. If the residual hydrocarbon shale in autoclave is taken as a shale oil system after hydrocarbon generation simulation, the oil saturation index (OSI) value of the shale samples in the autoclave after thermal simulation is the highest near the peak of oil generation, suggesting that maturity is one of the important factors affecting the exploration of shale oil.
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图 1 澳大利亚塔斯马尼亚洲采样区地质概况及采样位置
Ro为实测镜质体反射率;Ro(或Re)为计算或等效镜质反射率
修改自文献[20]。Figure 1. Geological overview of sampling area and sampling location in Tasmanian, Australian
表 1 实验样品基本地球化学特征
Table 1. Basic geochemical characteristics of samples
模拟温度/℃ S1/(mg·g-1) S2/(mg·g-1) Tmax/℃ ω(TOC)/% IH/(mg·g-1) IO/(mg·g-1) CP/% CR/% 原始样品 1.04 63.81 440 7.02 909 9 300 1.97 63.96 440 7.03 910 1 5.55 1.48 320 3.84 58.11 443 6.71 866 1 5.20 1.51 340 9.84 39.19 439 6.18 634 3 4.13 2.05 350 13.17 28.84 434 5.51 523 3 3.51 2.00 375 9.55 5.77 438 4.09 141 4 1.30 2.79 400 3.40 2.08 556 3.73 56 2 0.47 3.26 表 2 热模拟实验中排出油与滞留油族组分相对百分含量及其各族组分占比
Table 2. Relative percentage of expelled and retained oil fractions and proportion of each fraction to total oil
% 模拟温度/℃ 排出油族组分相对含量 滞留油族组分相对含量 饱和烃 芳烃 非烃 沥青质 饱和烃 芳烃 非烃 沥青质 300 31.6 32.5 24.3 11.6 14.6 57.8 19.5 8.1 320 25.9 36.4 22.5 15.2 9.6 50.6 23.5 16.3 340 18.4 25.7 21.1 34.8 6.1 35.5 30.0 28.4 350 23.1 30.2 24.9 21.8 7.9 37.2 30.4 24.5 375 38.9 36.4 14.9 9.8 12.0 54.4 16.0 17.6 400 8.4 64.4 16.8 10.4 14.7 57.7 19.5 8.1 模拟温度/ ℃ 排出油中族组分占总油比例 滞留油中族组分占总油比例 饱和烃 芳烃 非烃 沥青质 饱和烃 芳烃 非烃 沥青质 300 5.4 5.6 4.1 2.0 12.1 47.9 16.2 6.7 320 6.6 9.3 5.7 3.9 7.1 37.7 17.5 12.1 340 2.9 4.0 3.3 5.4 5.1 29.9 25.4 24.0 350 4.9 6.3 5.2 4.6 6.2 29.4 24.1 19.3 375 14.4 13.5 5.5 3.6 7.5 34.3 10.1 11.1 400 5.3 40.2 10.4 6.5 5.5 21.7 7.3 3.1 表 3 热模拟实验中排出油与滞留油及其族组分稳定碳同位素
Table 3. Stable carbon isotopes of fractions of expelled and retained oil in thermal simulation
‰ 模拟温度/℃ 排出油及族组分δ13CPDB 滞留油及族组分δ13CPDB 排出油 饱和烃 芳烃 非烃 沥青质 滞留油 饱和烃 芳烃 非烃 沥青质 300 -16.3 -16.9 -15.3 -18.0 -18.8 -14.0 -15.0 -13.6 -16.4 -18.4 320 -15.6 -15.8 -15.2 -17.2 -17.0 -14.0 -14.6 -14.2 -15.4 -16.3 340 -14.0 -15.6 -15.0 -14.6 -15.1 -13.1 -14.3 -13.2 -13.9 -13.6 350 -14.2 -15.0 -14.3 -14.6 -14.8 -12.9 -14.2 -13.0 -13.4 -14.0 375 -14.2 -15.9 -13.3 -16.8 -17.0 -12.4 -12.4 -12.2 -13.3 -14.4 400 -13.5 -22.5 -13.2 -15.5 -15.8 -12.4 -17.9 -12.2 -13.7 -14.4 -
[1] 吴庆余, 章冰, 宋一涛, 等. 水解和细菌降解作用对小球藻热模拟烷烃及生物标志物的影响[J]. 科学通报, 1998, 43(1): 76-80. https://www.cnki.com.cn/Article/CJFDTOTAL-KXTB199801019.htmWU Qingyu, ZHANG Bing, SONG Yitao, et al. The influence of hydrolysis and bacterial degradation on chlorella thermally simulated alkanes and biomarkers[J]. Chinese Science Bulletin, 1998, 43(1): 76-80. https://www.cnki.com.cn/Article/CJFDTOTAL-KXTB199801019.htm [2] 李超, 徐茂泉, 王开发, 等. 单细胞海藻热模拟生烃研究[J]. 厦门大学学报(自然科学版), 2001, 40(3): 764-769. https://www.cnki.com.cn/Article/CJFDTOTAL-XDZK200103018.htmLI Chao, XU Maoquan, WANG Kaifa, et al. Study on the thermal simulation for hydrocarbon generating by unicellular algae[J]. Journal of Xiamen University(Natural Science), 2001, 40(3): 764-769. https://www.cnki.com.cn/Article/CJFDTOTAL-XDZK200103018.htm [3] 孟庆强, 秦建中, 刘文斌, 等. 多细胞宏观底栖藻类生烃特点实验研究[J]. 石油学报, 2008, 29(6): 822-826. https://www.cnki.com.cn/Article/CJFDTOTAL-SYXB200806007.htmMENG Qingqiang, QIN Jianzhong, LIU Wenbin, et al. Experimental study on hydrocarbon generation of multi-cellular benthic macro alga[J]. Acta Petrolei Sinica, 2008, 29(6): 822-826. https://www.cnki.com.cn/Article/CJFDTOTAL-SYXB200806007.htm [4] 郭汝泰, 杨凤丽. 藻类有机质的成烃机制探讨[J]. 同济大学学报(自然科学版), 2002, 30(1): 41-45. https://www.cnki.com.cn/Article/CJFDTOTAL-TJDZ200201007.htmGUO Rutai, YANG Fengli. Inquisition to the hydrocarbon generation mechanism for algal organic matter[J]. Journal of Tongji University(Natural Science), 2002, 30(1): 41-45. https://www.cnki.com.cn/Article/CJFDTOTAL-TJDZ200201007.htm [5] 叶云, 刘文汇, 腾格尔, 等. 巢湖蓝藻腐殖化过程中形态与成份变化研究[J]. 微体古生物学报, 2012, 29(2): 152-160. https://www.cnki.com.cn/Article/CJFDTOTAL-WSGT201202005.htmYE Yun, LIU Wenhui, TENG Ge'er, et al. Research on cyanobacteria from the Chaohu Lake during a simulating process of decaying: changes in morphology and organic composition[J]. Acta Micropalaeontologica Sinica, 2012, 29(2): 152-160. https://www.cnki.com.cn/Article/CJFDTOTAL-WSGT201202005.htm [6] 纪玉, 刘文汇, 李玉成, 等. 安徽巢湖蓝藻早期成岩过程中微生物作用的实验室模拟[J]. 微体古生物学报, 2014, 31(4): 347-357. https://www.cnki.com.cn/Article/CJFDTOTAL-WSGT201404003.htmJI Yu, LIU Wenhui, LI Yucheng, et al. Laboratory simulation on the morphological and componential changes of cyanobacteria from the Chaohu Lake, Anhui Province during the early diagenesis[J]. Acta Micropalaeontologica Sinica, 2014, 31(4): 347-357. https://www.cnki.com.cn/Article/CJFDTOTAL-WSGT201404003.htm [7] 纪玉. 藻类有机质早期成岩作用模拟及其生烃潜力研究[D]. 合肥: 安徽大学, 2015.JI Yu. Simulated research on early diagenesis of algae organic matter and its hydrocarbon generation potential[D]. Hefei: Anhui University, 2015. [8] WU Yuandong, ZHANG Zhongning, SUN Lian, et al. The effect of pressure and hydrocarbon expulsion on hydrocarbon generation during pyrolyzing of continental type-Ⅲ kerogen source rocks[J]. Journal of Petroleum Science and Engineering, 2018, 170: 958-966. doi: 10.1016/j.petrol.2018.06.067 [9] MA Weijiao, HOU Lianhua, LUO Xia, et al. Generation and expulsion process of the Chang 7 oil shale in the Ordos Basin based on temperature-based semi-open pyrolysis: implications for in-situ conversion process[J]. Journal of Petroleum Science and Engineering, 2020, 190: 107035. doi: 10.1016/j.petrol.2020.107035 [10] 徐陈杰, 叶加仁, 刘金水, 等. 东海西湖凹陷平湖组Ⅲ型干酪根暗色泥岩生排烃模拟[J]. 石油与天然气地质, 2020, 41(2): 359-366. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT202002013.htmXU Chenjie, YE Jiaren, LIU Jinshui, et al. Simulation of hydrocarbon generation and expulsion for the dark mudstone with type-Ⅲ kerogen in the Pinghu Formation of Xihu Sag in East China Sea Shelf Basin[J]. Oil & Gas Geology, 2020, 41(2): 359-366. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT202002013.htm [11] 李剑, 马卫, 王义凤, 等. 腐泥型烃源岩生排烃模拟实验与全过程生烃演化模式[J]. 石油勘探与开发, 2018, 45(3): 445-454. https://www.cnki.com.cn/Article/CJFDTOTAL-SKYK201803011.htmLI Jian, MA Wei, WANG Yifeng, et al. Modeling of the whole hydrocarbon-generating process of sapropelic source rock[J]. Petroleum Exploration and Development, 2018, 45(3): 445-454. https://www.cnki.com.cn/Article/CJFDTOTAL-SKYK201803011.htm [12] 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 Geo-logy & Experiment, 2018, 40(4): 551-558. doi: 10.11781/sysydz201804551 [13] 郭凯. 鄂尔多斯盆地陇东地区长7段有效烃源岩及生排烃研究[J]. 石油实验地质, 2017, 39(1): 15-23. doi: 10.11781/sysydz201701015GUO Kai. Active source rocks of Chang 7 member and hydrocarbon generation and expulsion characteristics in Longdong area, Ordos Basin[J]. Petroleum Geology & Experiment, 2017, 39(1): 15-23. doi: 10.11781/sysydz201701015 [14] TANG Xuan, ZHANG Jinchuan, JIANG Zaixing, et al. Characteristics of solid residue, expelled and retained hydrocarbons of lacustrine marlstone based on semi-closed system hydrous pyrolysis: implications for tight oil exploration[J]. Fuel, 2015, 162: 186-193. [15] 李志明, 郑伦举, 马中良, 等. 烃源岩有限空间油气生排模拟及其意义[J]. 石油实验地质, 2011, 33(5): 447-451. doi: 10.11781/sysydz201105447LI Zhiming, ZHENG Lunju, MA Zhongliang, et al. Simulation of source rock for hydrocarbon generation and expulsion in finite space and its significance[J]. Petroleum Geology & Experiment, 2011, 33(5): 447-451. doi: 10.11781/sysydz201105447 [16] HAN Yuanjia, MAHLSTEDT N, HORSFIELD B. The Barnett shale: compositional fractionation associated with intraformational petroleum migration, retention, and expulsion[J]. AAPG Bulletin, 2015, 99(12): 2173-2202. [17] 黄振凯, 黎茂稳, 郑伦举, 等. 湖相烃源岩演化全过程中的孔隙演化机理: 基于地质样品与模拟实验的认识[J]. 石油实验地质, 2020, 42(4): 639-645. doi: 10.11781/sysydz202004639HUANG Zhenkai, LI Maowen, ZHENG Lunju, et al. Pore development in lacustrine source rock evolution: interpretation based on geological samples and simulation experiments[J]. Petroleum Geology & Experiment, 2020, 42(4): 639-645. doi: 10.11781/sysydz202004639 [18] SUN Jian, XIAO Xianming, CHENG Peng, et al. The relationship between oil generation, expulsion and retention of lacustrine shales: based on pyrolysis simulation experiments[J]. Journal of Petroleum Science and Engineering, 2021, 196: 107625. [19] XIE Xiaomin, WANG Ye, LIN Jingwen, et al. Geochemical characte-ristics of expelled and residual oil from artificial thermal maturation of an Early Permian Tasmanite shale, Australia[J]. Energies, 2021, 14(7218): 1-20. [20] REID C M, BURRETT C F. The geology and hydrocarbon potential of the Glaciomarine Lower Parmeener Supergroup, Tasmania Basin[C]//Conference Proceedings PESA's Eastern Australian Basin Symposium Ⅱ. Adelaide, SA, 2004: 265-275. [21] DUTTA S, GREENWOOD P F, BROCKE R, et al. New insights into the relationship between Tasmanites and tricyclic terpenoids[J]. Organic Geochemistry, 2006, 37(1): 117-127. [22] SANDVIK E I, YOUNG W A, CURRY D J. Expulsion from hydrocarbon sources: the role of organic absorption[J]. Organic Geochemistry, 1992, 19(1/3): 77-87. [23] RITTER U. Solubility of petroleum compounds in kerogen: implications for petroleum expulsion[J]. Organic Geochemistry, 2003, 34(3): 319-326. [24] BEHAR F, LORANT F, BUDZINSKI H, et al. Thermal stability of alkylaromatics in natural systems: kinetics of thermal decomposition of dodecylbenzene[J]. Energy and Fuels, 2002, 16(4): 831-841. [25] HILL R J, TANG Y C, KAPLAN I R. Insights into oil cracking based on laboratory experiments[J]. Organic Geochemistry, 2003, 34(12): 1651-1672. [26] TANG Yongchun, HUANG Yongsong, ELLIS G S, et al. A kinetic model for thermally induced hydrogen and carbon isotope fractionation of individual n-alkanes in crude oil[J]. Geochimica et Cosmochimica Acta, 2005, 69(18): 4505-4520. [27] 廖玉宏, 耿安松, 刘德汉, 等. 煤生烃过程中成熟度引起的碳同位素分馏效应[J]. 石油实验地质, 2007, 29(6): 583-588. doi: 10.11781/sysydz200706583LIAO Yuhong, GENG Ansong, LIU Dehan, et al. Carbon isotopic fractionation effect caused by maturity during the generation of coal-pyrolysis hyrocarbons[J]. Petroleum Geology & Experiment, 2007, 29(6): 583-588. doi: 10.11781/sysydz200706583 [28] 廖玉宏, 耿安松, 卢家烂. 初次运移中的同位素分馏效应[J]. 沉积学报, 2006, 24(5): 756-762. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB200605017.htmLIAO Yuhong, GENG Ansong, LU Jialan. Isotopic fractionation effect in primary migration[J]. Acta Sedimentologica Sinica, 2006, 24(5): 756-762. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB200605017.htm [29] 张爱云, 蔡云开, 初志明, 等. 沉积有机质中稳定碳同位素逆转现象初探[J]. 沉积学报, 1992, 10(4): 49-59. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB199204005.htmZHANG Aiyun, CAI Yunkai, CHU Zhiming, et al. Preliminary study on the reversed distribution of stable carbon isotopes in sedimentary organic matter[J]. Acta Sedimentologica Sinica, 1992, 10(4): 49-59. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB199204005.htm [30] 张中宁, 刘文汇, 郑建京, 等. 塔里木盆地塔北、塔中地区寒武—奥陶系碳酸盐岩中可溶有机组分的碳同位素逆转现象[J]. 矿物岩石, 2006, 26(4): 69-74. https://www.cnki.com.cn/Article/CJFDTOTAL-KWYS200604010.htmZHANG Zhongning, LIU Wenhui, ZHENG Jianjing, et al. Carbon isotopic reversed distribution of the soluble organic components for the Cambrian and Ordovician carbonate rocks in Tabei and Tazhong areas, Tarim Basin[J]. Journal of Mineralogy and Petrology, 2006, 26(4): 69-74. https://www.cnki.com.cn/Article/CJFDTOTAL-KWYS200604010.htm [31] 刘虎. 干酪根及其演化产物稳定碳同位素倒转分布的成因探讨及在塔里木油藏中的应用[D]. 广州: 中国科学院广州地球化学研究所, 2015.LIU Hu. Discussion on the origin of the reversal stable carbon isotope distributions between kerogen and its derivatives, and the geochemical significances to the marine crude oil reservoirs in Tarim Basin, NW China[D]. Guangzhou: Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 2015. [32] 万延周, 陈春峰, 王大卫, 等. 东海盆地某凹陷中南部平湖组烃源岩有机质碳同位素组成特征[J]. 非常规油气, 2020, 7(2): 18-25. https://www.cnki.com.cn/Article/CJFDTOTAL-FCYQ202002003.htmWAN Yanzhou, CHEN Chunfeng, WANG Dawei, et al. The carbon isotopic component characteristics of organic matter of Pinghu Formation source rocks in the center and south part of a certain depression, East China Sea Shelf Basin[J]. Unconventional Oil & Gas, 2020, 7(2): 18-25. https://www.cnki.com.cn/Article/CJFDTOTAL-FCYQ202002003.htm [33] 王大锐. 油气稳定同位素地球化学[M]. 北京: 石油工业出版社, 2000: 179-183.WANG Darui. Stable isotope geochemistry of oil and gas[M]. Beijing: Petroleum Industry Press, 2000: 179-183. [34] 卢双舫, 黄文彪, 陈方文, 等. 页岩油气资源分级评价标准探讨[J]. 石油勘探与开发, 2012, 39(2): 249-256. https://www.cnki.com.cn/Article/CJFDTOTAL-SKYK201202018.htmLU Shuangfang, HUANG Wenbiao, CHEN Fangwen, et al. Classification and evaluation criteria of shale oil and gas resources: discussion and application[J]. Petroleum Exploration and Development, 2012, 39(2): 249-256. https://www.cnki.com.cn/Article/CJFDTOTAL-SKYK201202018.htm [35] JARVIE D M. Shale resource systems for oil and gas: part 2—shale-oil resource systems[M]//BREYER J A. Shale reservoirs: giant resources for the 21st century: AAPG Memoir 97. Texas: AAPG, 2012: 89-119. [36] JARVIE D M. Components and processes affecting producibility and commerciality of shale resource systems[J]. Geologica Acta, 2014, 12(4): 307-325. [37] 黄振凯, 郝运轻, 李双建, 等. 鄂尔多斯盆地长7段泥页岩层系含油气性与页岩油可动性评价: 以H317井为例[J]. 中国地质, 2020, 47(1): 210-219. https://www.cnki.com.cn/Article/CJFDTOTAL-DIZI202001018.htmHUANG Zhenkai, HAO Yunqing, LI Shuangjian, et al. Oil-bearing potential, mobility evaluation and significance of shale oil in Chang 7 shale system in the Ordos Basin: a case study of well H317[J]. Geology in China, 2020, 47(1): 210-219. https://www.cnki.com.cn/Article/CJFDTOTAL-DIZI202001018.htm -