Lithofacies of Upper Ordovician Wufeng Formation in Sichuan Basin and its periphery
-
摘要: 上奥陶统五峰组分为页岩段和观音桥段。对比分析四川盆地及周缘五峰组页岩气钻井岩心以及测试数据,根据岩心和全岩矿物组分特征,以硅质矿物(石英)、黏土矿物和碳酸盐矿物为三端元,进行岩相划分。页岩段可识别出4种岩相类型:硅质页岩、含黏土硅质页岩、含灰硅质页岩以及含灰黏土质页岩;观音桥段发育含介壳泥质灰岩。页岩气钻井实测数据表明,页岩段4类页岩岩相品质(有机碳含量、脆性矿物含量以及含气量)差异较大,硅质页岩品质最优,含灰黏土质页岩品质最差。页岩段岩相类型以及观音桥段分布特征受控于沉积环境。川南永川地区等相对浅水的区域页岩厚度较大,但是硅质页岩厚度较小,页岩段整体品质较差,不建议作为水平井靶窗;川南威远地区受古陆和古地形影响,硅质页岩厚度较小,也不建议作为水平井靶窗;川东南焦石坝、武隆、丁山以及南川地区硅质页岩厚度超过4 m,可作为水平井靶窗。Abstract: The Upper Ordovician Wufeng Formation was divided into the shale and Guanyinqiao sections. Based on the comparative analysis of shale gas drilling cores and the whole rock mineral composition of the Wufeng Formation in the Sichuan Basin and its periphery, three end members including siliceous minerals (quartz), clay minerals and carbonate minerals were chosen for lithofacies classification. Four lithofacies types were identified in the shale section including siliceous shale, clayey siliceous shale, gray siliceous shale and gray clayey shale, while in the Guanyinqiao section, shell marl developed. The shale gas drilling showed that the four lithofacies types vary in TOC, brittle mineral and gas contents. The quality of siliceous shale is the best, and the quality of gray clayey shale is the worst. The lithofacies types of the shale section and the distribution characteristics of the Guanyinqiao section were controlled by the sedimentary environment. The shale thickness in Yongchuan area and other relatively shallow water areas in the southern Sichuan Basin is relatively large, but the thickness of siliceous shale is small, and the overall quality of the shale section is poor, so it is not recommended as the target window of horizontal wells. The thickness of siliceous shale in Weiyuan area in the southern Sichuan is small due to the influence of ancient land and topography, and it also is not recommended as the target window of horizontal wells. The thickness of siliceous shale in Jiaoshiba, Wulong, Dingshan and Nanchuan areas in the southeastern Sichuan Basin is more than 4 m, which can be regarded as a target window of horizontal wells.
-
Key words:
- shale gas /
- target window of horizontal well /
- siliceous shale /
- Ganyinqiao section /
- Wufeng Formation /
- Sichuan Basin
-
表 1 四川盆地及周缘五峰组页岩岩相参数统计
Table 1. Lithofacies parameters of Wufeng shale in Sichuan Basin and its periphery
岩相类型 样品个数 石英含量/% 有机碳含量/% 脆性矿物含量/% 含气量/(m3·t-1) 硅质页岩 12 67.6 4.6 72.1 5.2 含灰硅质页岩 4 42.0 3.5 68.3 3.6 含黏土硅质页岩 3 45.9 3.6 65.4 3.6 含灰黏土质页岩 4 33.4 1.2 52.1 1.1 注:数据来自焦页1、永页1、威页23-1、丁页2、彭页1井等。 -
[1] 张金川, 金之钧, 袁明生. 页岩气成藏机理和分布[J]. 天然气工业, 2004, 24(7): 15-18. https://www.cnki.com.cn/Article/CJFDTOTAL-TRQG200407004.htmZHANG Jinchuan, JIN Zhijun, YUAN Mingsheng. Reservoiring mechanism of shale gas and its distribution[J]. Natural Gas Industry, 2004, 24(7): 15-18. https://www.cnki.com.cn/Article/CJFDTOTAL-TRQG200407004.htm [2] CURTIS J B. Fractured shale-gas systems[J]. AAPG Bulletin, 2002, 86(11): 1921-1938. [3] 易积正, 王超. 四川盆地焦石坝地区龙马溪组海相页岩储层非均质性特征[J]. 石油实验地质, 2018, 40(1): 13-19. doi: 10.11781/sysydz201801013YI Jizheng, WANG Chao. Differential pore development characteristics in various shale lithofacies of Longmaxi Formation in Jiaoshiba area, Sichuan Basin[J]. Petroleum Geology and Experiment, 2018, 40(1): 13-19. doi: 10.11781/sysydz201801013 [4] 王超, 张柏桥, 舒志国, 等. 四川盆地涪陵地区五峰组-龙马溪组海相页岩岩相类型及储层特征[J]. 石油与天然气地质, 2018, 39(3): 485-497. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT201803007.htmWANG Chao, ZHANG Baiqiao, SHU Zhiguo, et al. Lithofacies types and reservoir characteristics of marine shales of the Wufeng Formation-Longmaxi Formation in Fuling area, the Sichuan Basin[J]. Oil & Gas Geology, 2018, 39(3): 485-497. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT201803007.htm [5] 熊亮. 川南威荣页岩气田五峰组-龙马溪组页岩沉积相特征及其意义[J]. 石油实验地质, 2019, 41(3): 326-332. doi: 10.11781/sysydz201903326XIONG Liang. Characteristics and significance of sedimentary facies of Wufeng-Longmaxi formation shale in Weirong Shale Gas Field, southern Sichuan Basin[J]. Petroleum Geology and Experiment, 2019, 41(3): 326-332. doi: 10.11781/sysydz201903326 [6] 葛忠伟, 樊莉, 钟文俊, 等. 威远龙马溪组黑色页岩非均质性及对开发的影响[J]. 非常规油气, 2019, 6(4): 33-39. https://www.cnki.com.cn/Article/CJFDTOTAL-FCYQ201904007.htmGE Zhongwei, FAN Li, ZHONG Wenjun, et al. Heterogeneity of black shale of Longmaxi Formation in Weiyuan and its impact on development[J]. Unconventional Oil & Gas, 2019, 6(4): 33-39. https://www.cnki.com.cn/Article/CJFDTOTAL-FCYQ201904007.htm [7] 洪亚飞, 王建忠, 孙强. 焦石坝页岩气储层产能影响因素分析[J]. 非常规油气, 2016, 3(5): 73-78. https://www.cnki.com.cn/Article/CJFDTOTAL-FCYQ201605012.htmHONG Yafei, WANG Jianzhong, SUN Qiang. Analysis of the influence factors for shale gas reservoir in Jiaoshiba area[J]. Unconventional Oil & Gas, 2016, 3(5): 73-78. https://www.cnki.com.cn/Article/CJFDTOTAL-FCYQ201605012.htm [8] 杨敬之, 穆恩之. 鄂西长阳宜都一带奥陶纪地层[J]. 古生物学报, 1954, 2(1): 59-82. https://www.cnki.com.cn/Article/CJFDTOTAL-GSWX195401002.htmYANG Jingzhi, MU Enzhi. The Ordovician stratigraphy of the Changyang-Yidu area, western Hubei[J]. Acta Palaeontologica Sinica, 1954, 2(1): 59-82. https://www.cnki.com.cn/Article/CJFDTOTAL-GSWX195401002.htm [9] 陈旭, 戎嘉余. 从生物地层学到大地构造学: 以华南奥陶系和志留系为例[J]. 现代地质, 1999, 13(4): 385-389. https://www.cnki.com.cn/Article/CJFDTOTAL-XDDZ199904003.htmCHEN Xu, RONG Jiayu. From biostratigraphy to tectonics: with Ordovician and Silurian of South China as an example[J]. Geoscience, 1999, 13(4): 385-389. https://www.cnki.com.cn/Article/CJFDTOTAL-XDDZ199904003.htm [10] 周雁, 陈洪德, 王成善, 等. 中扬子区海相地层层序样式及其油气地质意义[J]. 成都理工学院学报, 2002, 29(1): 26-30. https://www.cnki.com.cn/Article/CJFDTOTAL-CDLG200201004.htmZHOU Yan, CHEN Hongde, WANG Chengshan, et al. The sequence style of marine strata and its relationship with petroleum geology in the Mid-Yangze area[J]. Journal of Chengdu University of Technology, 2002, 29(1): 26-30. https://www.cnki.com.cn/Article/CJFDTOTAL-CDLG200201004.htm [11] 张金川, 聂海宽, 徐波, 等. 四川盆地页岩气成藏地质条件[J]. 天然气工业, 2008, 28(2): 151-156. https://www.cnki.com.cn/Article/CJFDTOTAL-TRQG200802057.htmZHANG Jinchuan, NIE Haikuan, XU Bo, et al. Geological condition of shale gas accumulation in Sichuan Basin[J]. Natural Gas Industry, 2008, 28(2): 151-156. https://www.cnki.com.cn/Article/CJFDTOTAL-TRQG200802057.htm [12] 何顺, 秦启荣, 范存辉, 等. 川东南丁山地区五峰-龙马溪组页岩储层特征及影响因素[J]. 油气藏评价与开发, 2019, 9(4): 61-67. https://www.cnki.com.cn/Article/CJFDTOTAL-KTDQ201904012.htmHE Shun, QIN Qirong, FAN Cunhui, et al. Shale reservoir characte-ristics and influencing factors of Wufeng-Longmaxi formation in Dingshan area, southeast Sichuan[J]. Reservoir Evaluation and Development, 2019, 9(4): 61-67. https://www.cnki.com.cn/Article/CJFDTOTAL-KTDQ201904012.htm [13] 许露露, 张焱林, 陈程, 等. 鄂西地区黄陵背斜周缘五峰组-龙马溪组页岩气储层及含气性特征[J]. 特种油气藏, 2019, 26(5): 26-32. https://www.cnki.com.cn/Article/CJFDTOTAL-TZCZ201905005.htmXU Lulu, ZHANG Yanlin, CHEN Cheng, et al. Shale gas reservoir and gas-bearing properties of Wufeng-Longmaxi formations in the periphery of Huangling anticline of western Hubei province[J]. Special Oil & Gas Reservoirs, 2019, 26(5): 26-32. https://www.cnki.com.cn/Article/CJFDTOTAL-TZCZ201905005.htm [14] 钟城, 秦启荣, 胡东风, 等. 川东南丁山地区五峰组-龙马溪组页岩气藏"六性"特征[J]. 油气地质与采收率, 2019, 26(2): 14-23. https://www.cnki.com.cn/Article/CJFDTOTAL-YQCS201902003.htmZHONG Cheng, QIN Qirong, HU Dongfeng, et al. Experimental study on "six properties" of shale gas reservoirs in the Wufeng-Longmaxi formation in Dingshan area, southeastern Sichuan Basin[J]. Petroleum Geology and Recovery Efficiency, 2019, 26(2): 14-23. https://www.cnki.com.cn/Article/CJFDTOTAL-YQCS201902003.htm [15] 杨振恒, 翟常博, 邓模, 等. 彭水及邻区五峰-龙马溪组成烃生物特征及意义[J]. 油气藏评价与开发, 2019, 9(5): 40-44. https://www.cnki.com.cn/Article/CJFDTOTAL-KTDQ201905005.htmYANG Zhenheng, ZHAI Changbo, DENG Mo, et al. Characteristics and significance of hydrocarbon-forming organisms of Wufeng-Longmaxi formation in Pengshui and its adjacent areas[J]. Reservoir Evaluation and Development, 2019, 9(5): 40-44. https://www.cnki.com.cn/Article/CJFDTOTAL-KTDQ201905005.htm [16] 龙鹏宇, 张金川, 李玉喜, 等. 重庆及其周缘地区下古生界页岩气成藏条件及有利区预测[J]. 地学前缘, 2012, 19(2): 221-233. https://www.cnki.com.cn/Article/CJFDTOTAL-DXQY201202032.htmLONG Pengyu, ZHANG Jinchuan, LI Yuxi, et al. Reservoir-forming conditions and strategic select favorable area of shale gas in the Lower Paleozoic of Chongqing and its adjacent areas[J]. Earth Science Frontiers, 2012, 19(2): 221-233. https://www.cnki.com.cn/Article/CJFDTOTAL-DXQY201202032.htm [17] 李双建, 肖开华, 沃玉进, 等. 南方海相上奥陶统-下志留统优质烃源岩发育的控制因素[J]. 沉积学报, 2008, 26(5): 872-880. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB200805024.htmLI Shuangjian, XIAO Kaihua, WO Yujin, et al. Developmental controlling factors of Upper Ordovician-Lower Silurian high quality source rocks in marine sequence, South China[J]. Acta Sedimentologica Sinica, 2008, 26(5): 872-880. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB200805024.htm [18] 王鸿祯. 中国古地理图集[M]. 北京: 地质出版社, 1985.WANG Hongzhen. Atlas of the paleogeography of China[M]. Beijing: Cartography Press, 1985. [19] 刘宝珺, 许效松. 中国南方岩相古地理图集(震旦纪-三叠纪)[M]. 北京: 科学出版社, 1994.LIU Baojun, XU Xiaosong. Lithofacies paleogeographic atlas of southern China[M]. Beijing: Science Press, 1994. [20] 梁狄刚, 郭彤楼, 陈建平, 等. 中国南方海相生烃成藏研究的若干新进展(一): 南方四套区域性海相烃源岩的分布[J]. 海相油气地质, 2008, 13(2): 1-16. https://www.cnki.com.cn/Article/CJFDTOTAL-HXYQ200902003.htmLIANG Digang, GUO Tonglou, CHEN Jianping, et al. Some progresses on studies of hydrocarbon generation and accumulation in marine sedimentary regions, Southern China (part 1): distribution of four suits of regional marine source rocks[J]. Marine Origin Petroleum Geology, 2008, 13(2): 1-16. https://www.cnki.com.cn/Article/CJFDTOTAL-HXYQ200902003.htm [21] 郑和荣, 胡宗全. 中国前中生代构造-岩相古地理图集[M]. 北京: 地质出版社, 2010.ZHENG Herong, HU Zongquan. Tectonic-lithofacies paleogeographic atlas of Former Paleozoic of China[M]. Beijing: Geolo-gical Press, 2010. [22] 郑和荣, 高波, 彭勇民, 等. 中上扬子地区下志留统沉积演化与页岩气勘探方向[J]. 古地理学报, 2013, 15(5): 645-656. https://www.cnki.com.cn/Article/CJFDTOTAL-GDLX201305011.htmZHENG Herong, GAO Bo, PENG Yongmin, et al. Sedimentary evolution and shale gas exploration direction of the Lower Silurian in Middle-Upper Yangtze area[J]. Journal of Palaeogeography, 2013, 15(5): 645-656. https://www.cnki.com.cn/Article/CJFDTOTAL-GDLX201305011.htm [23] 冯增昭, 彭勇民, 金振奎, 等. 中国南方寒武纪和奥陶纪岩相古地理[M]. 北京: 地质出版社, 2004.FENG Zengzhao, PENG Yongmin, JIN Zhenkui, et al. Lithofacies palaeogeography of the Cambrian and Ordovicion in South China[M]. Beijing: Geological Publishing House, 2004. [24] 穆恩之, 李积金, 葛梅钰, 等. 华中区上奥陶统笔石[M]. 北京: 科学出版社, 1993.MU Enzhi, LI Jijin, GE Meijue, et al. Ordovician graptolite in central China region[M]. Beijing: Science Press, 1993. [25] 戎嘉余, 陈旭, 王怿, 等. 奥陶-志留纪之交黔中古陆的变迁: 证据与启示[J]. 中国科学(地球科学), 2011, 41(10): 1407-1415. https://www.cnki.com.cn/Article/CJFDTOTAL-JDXK201110003.htmRONG Jiayu, CHEN Xu, WANG Yi, et al. Northward expansion of central Guizhou Oldland through the Ordovician and Silurian transition: evidence and implications[J]. Scientia Sinica (Terrae), 2011, 41(10): 1407-1415. https://www.cnki.com.cn/Article/CJFDTOTAL-JDXK201110003.htm [26] WILLIAMS S H. The Ordovician-Silurian boundary graptolite fauna of Dob's Linn, southern Scotland[J]. Palaeontology, 1983, 26: 605-639. [27] RONG Jiayu, MELCHIN M J, WILLIAMS S H, et al. Report of the restudy of the defined global stratotype of the base of the Silurian System[J]. Episodes, 2008, 31(3): 315-318. [28] CHEN Xu, MELCHIN M J, SHEETS H D, et al. Patterns and processes of latest Ordovician graptolite extinction and recovery based on data from South China[J]. Journal of Paleontology, 2005, 79(5): 842-861.