Spatial-temporal modelling of oil and gas accumulation in Changxing Formation in the Shunan area, Sichuan Basin
-
摘要: 四川盆地蜀南地区上二叠统长兴组下伏3套烃源岩,分别为下志留统龙马溪组泥页岩、中二叠统泥质岩、上二叠统龙潭组煤系,长兴组已发现多个大中型气田,但对天然气的烃源一直认识不清。通过天然气组成和碳同位素分析表明,该区长兴组天然气以原油裂解气为主、甲烷含量高、干燥系数大,属于典型的干气;结合储层显微特征和包裹体均一温度分析测试,并综合分析油气成藏时空匹配关系,首次发现并证实蜀南地区长兴组天然气主要来源于深层志留系烃源岩,并混入少量的龙潭组煤系成因气;长兴组储层未捕获各期烃源岩生油高峰期生成的液态烃,以充气聚气为主;燕山运动早中期为主要充气期,而燕山末期—喜马拉雅早期为局部天然气充气期,与川东地区长兴组以龙潭组煤系来源的天然气不同。油气成藏时空匹配是圈闭有效捕获油气的关键,决定着油气来源和成藏富集程度,历史地、动态地揭示油气运聚过程是现代油气成藏研究的核心。Abstract: There are three sets of source rocks below the Changxing Formation in the southern Sichuan Basin, including the mud shale in Lower Silurian Longmaxi Formation, the argillaceous rock in Middle Permian, and the coal series in Upper Permian Longtan Formation. Many large and medium-sized gas fields have been discovered in the Changxing Formation, but the understanding of the source of natural gas is still unclear. The natural gas composition and carbon isotope analyses show that the natural gas of Changxing Formation in this area is mainly secondary gas (from crude oil cracking) and is characterized by high methane content and high dryness coefficient, which belongs to typical dry gas. Combined with the reservoir microscopic characteristics and the inclusion homogenization temperatures, a spatial-temporal model of hydrocarbon accumulation was constructed. The natural gas of Changxing Formation in the southern Sichuan Basin is mainly from a deep Silurian hydrocarbon source mixed with a small amount of coal series gas in the Longtan Formation. The reservoir in Changxing Formation did not capture the liquid hydrocarbon generated by the source rock at the peak of oil generation stages, so it mainly accumulates gas. The early and middle period of Yanshan Movement is the main period of gas accumulation, with partial accumulation in the Yanshanian-early Himalayan. The natural gas of Changxing Formation in the southern Sichuan Basin is different from that in the eastern Sichuan which is mainly from the coal series. The spatial-temporal timing is the key to effectively capture oil and gas in traps and determines the source and accumulation enrichment of oil and gas. It is the core of modern petroleum accumulation research to reveal the migration and accumulation process of oil and gas through history.
-
表 1 四川盆地蜀南地区长兴组天然气组分统计
Table 1. Statistics of natural gas components of Changxing Formation in Shunan area, Sichuan Basin
构造 甲烷含量/% 乙烷含量/% C2+含量/% lg(C1/C2+) CO2含量/(g·m-3) N2含量/% 样品数 丹凤场 98.19 0.47 0.51 2.29 8.46 0.33 6 李子坝 98.66 0.51 0.55 2.22 11.12 0.19 10 东山 96.97 0.69 0.75 2.12 8.18 0.80 6 来苏 97.98 0.64 0.70 2.15 10.37 0.76 3 临峰场 97.49 0.58 0.61 2.20 24.75 0.54 6 塘河 98.23 0.33 0.35 2.45 17.00 0.33 8 永安场 98.32 0.53 0.59 2.22 15.20 0.30 4 自流井 97.64 0.35 0.39 2.39 0.64 1.64 5 德胜 98.33 0.58 0.63 2.19 0.74 0.27 3 古佛山 97.83 0.84 0.96 2.01 16.96 0.31 3 九奎山 97.94 0.65 0.71 2.14 0.98 0.33 10 龙洞坪 98.14 0.69 0.75 2.12 13.43 0.36 8 阳高寺 98.81 0.48 0.52 2.28 0.87 0.58 11 鹿角场 98.36 0.46 0.50 2.29 11.78 0.12 12 河包场 98.12 0.52 0.54 2.26 12.93 0.67 15 黄家场 96.86 0.89 0.91 2.03 49.47 0.66 5 界石场 98.59 0.53 0.55 2.25 0.73 0.79 9 白节滩 98.37 0.49 0.56 2.25 10.56 0.43 5 表 2 川东地区与蜀南地区天然气组成及碳同位素分析
Table 2. Composition and carbon isotope analysis of natural gas in eastern Sichuan and Shunan area
地区 构造 井号 产层 δ13C1/‰ δ13C2/‰ CH4/% C2+/% lg(C1/C2+) 蜀南 丹风场 丹7 P3ch -34.1 -32.8 98.92 0.44 2.35 蜀南 丹风场 丹7 P3ch -32.0 -33.6 98.92 0.44 2.35 蜀南 丹风场 丹10 P3ch -32.5 -33.9 98.66 0.54 2.26 蜀南 朱沱 朱3 P3ch -32.9 -33.1 98.27 0.55 2.26 蜀南 阳高寺 寺41 P3ch -34.2 -33.3 94.42 0.57 2.22 蜀南 龙洞坪 洞21-1 P3ch -34.1 -30.6 98.14 0.75 2.12 蜀南 荷包场 包004-X1 P3ch -33.0 -34.6 98.12 0.54 2.26 蜀南 荷包场 包38C1 P3ch -32.8 -34.5 91.71 0.66 2.14 蜀南 界石场 界14 P3ch -33.9 -35.6 98.50 0.79 2.09 川东 卧龙河 卧3 T1j15 -32.7 -28.9 92.91 1.33 1.84 川东 卧龙河 卧6 T1j15 -32.6 -28.2 92.92 1.45 1.81 川东 卧龙河 卧25 T1j15 -33.0 -29.0 93.00 1.20 1.89 川东 卧龙河 卧19 T1j34 -32.6 -28.9 92.89 1.43 1.81 川东 卧龙河 卧17 T1j14 -32.4 -28.9 94.94 1.11 1.93 川东 卧龙河 卧5 T1j13 -33.1 -29.4 94.36 1.41 1.83 川东 板东 板东4 P3ch -32.4 -30.9 91.70 1.76 1.72 -
[1] CLARKE R H. Reservoir properties of conglomerates and conglo-meratic sandstones: geologic notes[J]. AAPG Bulletin, 1979, 63(5): 799-803. [2] 李延钧, 江波, 张永庶, 等. 柴西狮子沟构造油气成藏期与成藏模式[J]. 新疆石油地质, 2008, 29(2): 176-178. https://www.cnki.com.cn/Article/CJFDTOTAL-XJSD200802014.htmLI Yanjun, JIANG Bo, ZHANG Yongxi, et al. Hydrocarbon accumulation stages and model of Shizigou structural oilfield in western Qaidam Basin[J]. Xinjiang Petroleum Geology, 2008, 29(2): 176-178. https://www.cnki.com.cn/Article/CJFDTOTAL-XJSD200802014.htm [3] 李延钧, 李其荣, 王廷栋, 等. 泸州古隆起下三叠统嘉陵江组成藏地球化学特征[J]. 石油与天然气地质, 2006, 27(3): 363-369. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT200603010.htmLI Yanjun, LI Qirong, WANG Tingdong, et al. Geochemical research of hydrocarbon reservoiring in Lower Triassic Jialingjiang Formation in Luzhou palaeohigh[J]. Oil & Gas Geology, 2006, 27(3): 363-369. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT200603010.htm [4] 李延钧, 宋国奇, 李文涛, 等. 济阳坳陷东营凹陷北带丰深1井区深层沙四下古油藏与天然气成因[J]. 石油与天然气地质, 2010, 31(2): 173-179. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT201002009.htmLI Yanjun, SONG Guoqi, LI Wentao, et al. A fossil oil-reservoir and the gas origin in the lower Sha-4 member of the well Fengshen-1 area, the north Dongying zone of the Jiyang Depression[J]. Oil & Gas Geology, 2010, 31(2): 173-179. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT201002009.htm [5] 杨家静, 王一刚, 王兰生, 等. 四川盆地东部长兴组—飞仙关组气藏地球化学特征及气源探讨[J]. 沉积学报, 2002, 20(2): 349-353. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB200202026.htmYANG Jiajing, WANG Yigang, WANG Lansheng, et al. The origin of natural gases and geochemistry characters of Changxing reef and Feixianguan oolitic beach gas reservoirs in eastern Sichuan Basin[J]. Acta Sedimentologica Sinica, 2002, 20(2): 349-353. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB200202026.htm [6] 冯冲, 郭彤楼, 邹华耀, 等. 川东北地区飞仙关组—长兴组天然气富集机制[J]. 现代地质, 2013, 27(4): 907-914. doi: 10.3969/j.issn.1000-8527.2013.04.017FENG Chong, GUO Tonglou, ZOU Huayao, et al. Enriched mechanism of natural gas in the Feixianguan-Changxing formations in the northeast Sichuan Basin[J]. Geoscience, 2013, 27(4): 907-914. doi: 10.3969/j.issn.1000-8527.2013.04.017 [7] 秦胜飞, 杨雨, 吕芳, 等. 四川盆地龙岗气田长兴组和飞仙关组气藏天然气来源[J]. 天然气地球科学, 2016, 27(1): 41-49. https://www.cnki.com.cn/Article/CJFDTOTAL-TDKX201601006.htmQIN Shengfei, YANG Yu, LV Fang, et al. The gas origin in Changxing-Feixianguan gas pools of Longgang gasfield in Sichuan Basin[J]. Natural Gas Geoscience, 2016, 27(1): 41-49. https://www.cnki.com.cn/Article/CJFDTOTAL-TDKX201601006.htm [8] 杨家静. 四川盆地乐山—龙女寺古隆起震旦系油气藏形成演化研究[D]. 成都: 西南石油学院, 2002.YANG Jiajing. Study on Formation and evolution of Sinian petro-leum pools in Leshan-Longnusi Paleo-uplift, Sichuan Basin[D]. Chengdu: Southwest Petroleum University, 2002. [9] 王鹏. 川西坳陷中段上三叠统—侏罗系天然气成藏地球化学研究[D]. 成都: 成都理工大学, 2015.WANG Peng. Geochemistry of natural gas accumulation of Upper Triassic-Jurassic in middle part of West Sichuan Depression[D]. Chengdu: Chengdu University of Technology, 2015. [10] 李延钧, 陈义才, 杨远聪, 等. 鄂尔多斯下古生界碳酸盐烃源岩评价与成烃特征[J]. 石油与天然气地质, 1999, 20(4): 349-353. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT199904017.htmLI Yanjun, CHEN Yicai, YANG Yuancong, et al. Source rock evaluation and characteristics of hydrocarbon generation from Lower Paleozoic carbonate in Ordos Basin[J]. Oil & Gas Geology, 1999, 20(4): 349-353. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT199904017.htm [11] 王琳霖, 浮昀, 方诗杰. 鄂尔多斯盆地东缘马家沟组元素地球化学特征及古沉积环境[J]. 石油实验地质, 2018, 40(4): 519-525. doi: 10.11781/sysydz201804519WANG Linlin, FU Yun, FANG Shijie. Elemental geochemical characteristics and geological significance of Majiagou Formation, eastern Ordos Basin[J]. Petroleum Geology & Experiment, 2018, 40(4): 519-525. doi: 10.11781/sysydz201804519 [12] 李延钧, 陈义才, 徐志明, 等. 低丰度高演化海相碳酸盐烃源岩有机质原生性研究[J]. 沉积学报, 2000, 18(1): 146-150. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB200001023.htmLI Yanjun, CHEN Yicai, XU Zhiming, et al. The Study on indigenous characteristics of organic matter in marine carbonate hydrocarbon source rock with low abundance and high evolution[J]. Acta Sedimen Tologica Sinica, 2000, 18(1): 146-150. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB200001023.htm [13] 董才源, 谢增业, 裴森奇, 等. 四川盆地中二叠统天然气地球化学特征及成因判识[J]. 断块油气田, 2018, 25(4): 450-454. https://www.cnki.com.cn/Article/CJFDTOTAL-DKYT201804009.htmDONG Caiyuan, XIE Zengye, PEI Senqi, et al. Natural gas geoche-mical characteristics and genetic type identification of Middle Permian in Sichuan Basin[J]. Fault-Block Oil & Gas Field, 2018, 25(4): 450-454. https://www.cnki.com.cn/Article/CJFDTOTAL-DKYT201804009.htm [14] 金惠, 杨威, 夏吉文, 等. 蜀南低缓构造区须家河组岩性气藏形成条件与勘探潜力[J]. 石油与天然气地质, 2018, 39(2): 300-308. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT201802010.htmJIN Hui, YANG Wei, XIA Jiwen, et al. Lithologic gas reservoir formation and exploration potential of the Xujiahe Formation in gently structured zones, southern Sichuan Basin[J]. Oil & Gas Geology, 2018, 39(2): 300-308. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT201802010.htm [15] 李延钧, 李其荣, 梁艳, 等. 应用烃类分段捕获原理研究油气运移聚集过程[J]. 天然气工业, 2007, 27(6): 31-34. https://www.cnki.com.cn/Article/CJFDTOTAL-TRQG200706009.htmLI Yanjun, LI Qiyong, LIANG Yan, et al. Hydrocarbon migration and accumulation by phased capture principle[J]. Natural Gas Industry, 2007, 27(6): 31-34. https://www.cnki.com.cn/Article/CJFDTOTAL-TRQG200706009.htm [16] 李其荣, 王廷栋, 李延钧, 等. 全烃地球化学方法在复杂烃源研究中的应用[J]. 西南石油学院学报, 2005, 27(3): 1-4. https://www.cnki.com.cn/Article/CJFDTOTAL-XNSY200503001.htmLI Qirong, WANG Tingdong, LI Yanjun, et al. The application of the Whole-Hydrocarbon geochemistry method in the complex hydrocarbon source research[J]. Journal of Southwest Petroleum Institute, 2005, 27(3): 1-4. https://www.cnki.com.cn/Article/CJFDTOTAL-XNSY200503001.htm [17] 张鹏, 张金功, 张亮, 等. 济阳坳陷渤南洼陷沙河街组二段多源供烃成藏模式[J]. 石油实验地质, 2018, 40(2): 159-167. doi: 10.11781/sysydz201802159ZHANG Peng, ZHANG Jingong, ZHANG Liang, et al. Reservoir-forming pattern with multiple sources in second member of Shahejie Formation, Bonan Sag, Jiyang Depression, Bohai Bay Basin[J]. Petroleum Geology & Experiment, 2018, 40(2): 159-167. doi: 10.11781/sysydz201802159 [18] 戴金星. 天然气地质学概论[M]. 北京: 石油工业出版社, 1999.DAI Jinxing. Natural gas geology[M]. Beijing: Petroleum Industry Press, 1999. [19] 蒋裕强, 罗明生, 张虎, 等. 蜀南地区龙潭组煤层气储层特征及资源潜力[J]. 西南石油大学学报(自然科学版), 2017, 39(1): 43-52. https://www.cnki.com.cn/Article/CJFDTOTAL-XNSY201701005.htmJIANG Yuqiang, LUO Mingsheng, ZHANG Hu, et al. Characteristics of CBM reservoirs and their resource potential in the southern Sichuan Basin[J]. Journal of Southwest Petroleum University (Science & Technology Edition), 2017, 39(1): 43-52. https://www.cnki.com.cn/Article/CJFDTOTAL-XNSY201701005.htm [20] 方俊华, 朱炎铭, 魏伟, 等. 蜀南地区龙马溪组页岩气成藏基础分析[J]. 特种油气藏, 2010, 17(6): 46-49. https://www.cnki.com.cn/Article/CJFDTOTAL-TZCZ201006011.htmFANG Junhua, ZHU Yanming, WEI Wei, et al. Basic geologic analysis of shale gas accumulation in the Longmaxi Formation in Shunan region[J]. Special Oil and Gas Reservoirs, 2010, 17(6): 46-49. https://www.cnki.com.cn/Article/CJFDTOTAL-TZCZ201006011.htm [21] 罗冰, 谭秀成, 李凌, 等. 蜀南地区长兴组顶部岩溶不整合的发现及其油气地质意义[J]. 石油学报, 2010, 31(3): 408-414. https://www.cnki.com.cn/Article/CJFDTOTAL-SYXB201003009.htmLUO Bing, TAN Xiucheng, LI Ling, et al. Discovery and geologic significance of paleokarst unconformity between Changxing Formation and Feixianguan Formation in Shunan area of Sichuan Basin[J]. Acta Petrolei Sinica, 2010, 31(3): 408-414. https://www.cnki.com.cn/Article/CJFDTOTAL-SYXB201003009.htm [22] 李其荣, 杜本强, 隆辉, 等. 蜀南地区天然气地质特征及勘探方向[J]. 天然气工业, 2009, 29(10): 21-23. https://www.cnki.com.cn/Article/CJFDTOTAL-TRQG200910006.htmLI Qirong, DU Benqiang, LONG Hui, et al. Geologic characteristics of gas reservoirs and exploration direction in southern Sichuan Basin[J]. Natural Gas Industry, 2009, 29(10): 21-23. https://www.cnki.com.cn/Article/CJFDTOTAL-TRQG200910006.htm [23] 李延钧, 刘欢, 刘家霞, 等. 页岩气地质选区及资源潜力评价方法[J]. 西南石油大学学报(自然科学版), 2011, 33(2): 28-34. https://www.cnki.com.cn/Article/CJFDTOTAL-XNSY201102003.htmLI Yanjun, LIU Huan, LIU Jiaxia, et al. Geological regional selection and an evaluation method of resource potential of shale gas[J]. Journal of Southwest Petroleum University (Science & Techno-logy Edition), 2011, 33(2): 28-34. https://www.cnki.com.cn/Article/CJFDTOTAL-XNSY201102003.htm [24] 董大伟, 赵利, 李婷婷, 等. 渤海湾盆地冀中坳陷典型斜坡带成因机制及油气成藏特征[J]. 石油实验地质, 2019, 41(4): 498-507. doi: 10.11781/sysydz201904498DONG Dawei, ZHAO Li, LI Tingting, et al. Evolution mechanism and hydrocarbon reservoir characteristics of typical slope zones in Jizhong Depression, Bohai Bay Basin[J]. Petroleum Geology & Experiment, 2019, 41(4): 498-507. doi: 10.11781/sysydz201904498 [25] KINLEY T J, COOK L W, BREYER J A, et al. Hydrocarbon potential of the Barnett shale (Mississippian), Delaware Basin, west Texas and southeastern New Mexico[J]. AAPG Bulletin, 2008, 92(8): 967-991. [26] MONTGOMERY S L, JARVIE D M, BOWKER K A, et al. Mississippian Barnett shale, Fort Worth Basin, north-central Texas: gas-shale play with multi-trillion cubic foot potential[J]. AAPG Bulletin, 2005, 89(2): 155-175. [27] 谢启超, 冯波, 宋鹏, 等. 合水地区长7致密砂岩储层微观孔喉结构分形特征[J]. 断块油气田, 2019, 26(2): 215-219. https://www.cnki.com.cn/Article/CJFDTOTAL-DKYT201902018.htmXIE Qichao, FENG Bo, SONG Peng, et al. Fractal characteristics of microscopic pore-throat structures of Chang 7 tight sandstone reservoirs, Heshui area, Ordos Basin[J]. Fault-Block Oil and Gas Field, 2019, 26(2): 215-219. https://www.cnki.com.cn/Article/CJFDTOTAL-DKYT201902018.htm [28] BURNAMAN M D, XIA Wenwu, SHELTON J. Shale gas play screening and evaluation criteria[J]. China Petroleum Exploration, 2009, 14(3): 51-64. [29] 李延钧, 赵圣贤, 李跃纲, 等. 川西北地区九龙山气田天然气成因与来源探讨[J]. 天然气地球科学, 2013, 24(4): 755-767. https://www.cnki.com.cn/Article/CJFDTOTAL-TDKX201304016.htmLI Yanjun, ZHAO Shengxian, LI Yuegang, et al. Natural gas genesis and sources in Jiulongshan Gas Field, northwest Sichuan Basin[J]. Natural Gas Geoscience, 2013, 24(4): 755-767. https://www.cnki.com.cn/Article/CJFDTOTAL-TDKX201304016.htm -