Significance of water absorption characteristics and difference of pore structures in the Cambrian shale intervals, Yichang area for shale reservoir evaluation

doi:10.13745/j.esf.sf.2022.5.38

Abstract

Abstract:

The Cambrian Shuijingtuo shale formation of Well ZK003, Liuxi, Yichang area is selected to study its pore development characteristics, where different formation layers are compared through water absorption experiment, helium porosity test, organic carbon content determination, and mineral composition analysis. The results of the study show that the Cambrian shale formation can be divided into members 1-4 from bottom to top, and different members have very different pore characteristics. In general, the higher the TOC content, the greater the water saturation limit (per gram of shale weight); and the higher the initial water absorption rate, the greater the porosity of shale. In shales from the organic-rich members 1 and 2, the TOC content ranges from 1.8% to 11.5%, averaging 4.6%; the helium porosity ranges from 1.6% to 5.8%, averaging 3.9%; and the water absorption saturation limit is between 6.1-21.4 mg/g shale weight, or on average 15.3 mg/g shale weight. Between the two members, shale from member 1 has higher TOC content but significantly lower porosity, water absorption value, and water absorption rate. The carbonate content in member 1 shows a good negative correlation with the water absorption value; whereas a positive correlation is observed for the clay content in member 2. It is believed that in member 1 carbonate cementation hinders the development of micropores and nanopores; while in member 2, development of micropores, which have large specific surface area and autogenic to porous clay, lead to strong water absorption. Overall, member 2 of the organic-rich shale formation has high porosity and good roof/floor isolation by overlaying marl and carbonate, which is conducive to the enrichment and preservation of shale gas, therefore making it a high-quality shale gas reservoir in the study area. The research results can be used for screening high-quality Cambrian shale reservoirs and predicting shale gas exploration “sweet spots”.

Key words: Yichang area, Lower-Cambrian, water absorption experiment, pore structure, preservation conditions

CLC Number:

P618.130.2

ZHANG Liuliu, CHEN Gengxin, LE Xingfu, ZHANG Yu, SHAO Deyong, YAN Jianping, MENG Kang, ZHANG Tongwei. Significance of water absorption characteristics and difference of pore structures in the Cambrian shale intervals, Yichang area for shale reservoir evaluation[J]. Earth Science Frontiers, 2023, 30(3): 138-150.

Figures/Tables 9

Table 1 Comparison of TOC and porosity data for Cambrian organic-rich shales from different regions of southern China

区域	地层	页岩层位	TOC含量/%	孔隙度/%	数据来源
川东南地区	下志留统	龙马溪组	0.51~25.7 2.59	4.5~8.09 6.13	文献[19]
黔北地区	下志留统	龙马溪组	0.7~3.55 1.87	1~10 6.4	文献[20]
川东南地区	下寒武统	牛蹄塘组	2~33.41 8.93	2.10	文献[21-22]
川西南	下寒武统	筇竹寺组	0.55~3.44 1.39	0.94~4.74 2.5	文献[14]
鄂西地区	下寒武统	水井沱组	1.23~10.45 3.45	0.96~4.59 2.0~3.12	文献[12,23-24]

Fig.1 Simplified geological structural map of Yichang area. Modified after [17].

Fig.2 Stratigraphic column diagram of Well ZK003

Fig.3 Asphalt-containing shale at the lithological boundary between member 1 and the Yanjiahe Formation

Fig.4 TOC, water absorption, porosity and mineral composition profiles in Well ZK003

Fig.5 Comparison of water absorption characteristics at the shale interval boundaries in Well ZK003

Fig.6 Comparison of the characteristics of water absorption (left) and initial absorption rate (right) between organic-rich members 1 and 2 in Well ZK003

Fig.7 Relationship between helium porosity and water absorption value (a) or porosity calculated from water absorption measurement (b) in Well ZK003

Fig.8 Relationship between water absorption value and geochemical proxies in Well ZK003

References 58

[1]	LOUCKS R G, RUPPEL S C. Mississippian Barnett Shale: lithofacies and depositional setting of a deep-water shale-gas succession in the Fort Worth Basin, Texas[J]. AAPG Bulletin, 2007, 91(4): 579-601. DOI URL
[2]	LOUCKS R G, REED R M, RUPPEL S C, et al. Morphology, genesis, and distribution of nanometer-scale pores in siliceous mudstones of the Mississippian barnett shale[J]. Journal of Sedimentary Research, 2009, 79(12): 848-861. DOI URL
[3]	李佳欣. 观音桥段地质特征及其对页岩气产量的影响: 以南川地区为例[J]. 油气藏评价与开发, 2018, 8(4): 68-72.
[4]	LOUCKS R G, REED R M, RUPPEL S C, et al. Spectrum of pore types and networks in mudrocks and a descriptive classification for matrix-related mudrock pores[J]. AAPG Bulletin, 2012, 96(6): 1071-1098. DOI URL
[5]	TIAN H, PAN L, XIAO X M, et al. A preliminary study on the pore characterization of Lower Silurian black shales in the Chuandong Thrust Fold Belt, southwestern China using low pressure N₂ adsorption and FE-SEM methods[J]. Marine and Petroleum Geology, 2013, 48: 8-19. DOI URL
[6]	彭女佳, 何生, 郝芳, 等. 川东南彭水地区五峰组-龙马溪组页岩孔隙结构及差异性[J]. 地球科学, 2017, 42(7): 1134-1146.
[7]	王超, 张柏桥, 舒志国, 等. 焦石坝地区五峰组-龙马溪组页岩纹层发育特征及其储集意义[J]. 地球科学, 2019, 44(3): 972-982.
[8]	MILLIKEN T, SHAW J, EMSLIE R. The South Africa-Vietnam rhino horn trade nexus: a deadly combination of institutional lapses, corrupt wildlife industry professionals and Asian crime syndicates[M]. Johannesburg: TRAFFIC, 2012.
[9]	陈居凯, 朱炎铭, 付常青, 等. 滇东下寒武统筇竹寺组页岩矿物组成特征及意义[J]. 煤炭技术, 2016, 35(9): 101-103.
[10]	罗超, 刘树根, 孙玮, 等. 鄂西—渝东地区下寒武统牛蹄塘组黑色页岩孔隙结构特征[J]. 东北石油大学学报, 2014, 38(2): 8-17, 79, 5.
[11]	陈相霖, 郭天旭, 石砥石, 等. 陕南地区牛蹄塘组页岩孔隙结构特征及吸附能力[J]. 岩性油气藏, 2019, 31(5): 52-60.
[12]	李海, 刘安, 罗胜元, 等. 鄂西宜昌斜坡区寒武系页岩储层发育特征: 以鄂宜页1井为例[J]. 石油实验地质, 2019, 41(1): 76-82.
[13]	GAO B, LIU Z, SHU Z, et al. Reservoir characteristics and exploration of the Lower Cambrian shale gas in the Middle-Upper Yangtze area[J]. Oil and Gas Geology, 2020, 41(2): 284-294.
[14]	王鹏威, 刘忠宝, 金之钧, 等. 川西南地区下寒武统筇竹寺组页岩气纵向差异富集主控因素[J]. 地球科学, 2019, 44(11): 3628-3638.
[15]	韩双彪, 张金川, 杨超, 等. 渝东南下寒武页岩纳米级孔隙特征及其储气性能[J]. 煤炭学报, 2013, 38(6): 1038-1043.
[16]	邹才能, 赵群, 董大忠, 等. 页岩气基本特征、主要挑战与未来前景[J]. 天然气地球科学, 2017, 28(12): 1781-1796.
[17]	罗胜元, 陈孝红, 岳勇, 等. 中扬子宜昌地区沉积-构造演化与寒武系页岩气富集规律[J]. 天然气地球科学, 2020, 31(8): 1052-1068.
[18]	ZHAO W Z, LI J Z, YANG T, et al. Geological difference and its significance of marine shale gases in South China[J]. Petroleum Exploration and Development, 2016, 43(4): 547-559. DOI URL
[19]	杨巍, 薛莲花, 唐俊, 等. 页岩孔隙度测量实验方法分析与评价[J]. 沉积学报, 2015, 33(6): 1258-1264.
[20]	李贤庆, 王哲, 郭曼, 等. 黔北地区下古生界页岩气储层孔隙结构特征[J]. 中国矿业大学学报, 2016, 45(6): 1172-1183.
[21]	聂海宽, 边瑞康, 张培先, 等. 川东南地区下古生界页岩储层微观类型与特征及其对含气量的影响[J]. 地学前缘, 2014, 21(4): 331-343.
[22]	张亚军. 四川盆地及邻区下古生界海相泥页岩吸水实验研究[D]. 兰州: 兰州大学, 2019.
[23]	杨松平, 赵征, 谭华. 鄂西地区水井沱组页岩气地质条件研究[J]. 中国煤炭地质, 2015, 27(4): 26-29.
[24]	陈孝红, 危凯, 张保民, 等. 湖北宜昌寒武系水井沱组页岩气藏主控地质因素和富集模式[J]. 中国地质, 2018, 45(2): 207-226.
[25]	何伟, 张金川, 李莉, 等. 湘西北常页1井下寒武统牛蹄塘组页岩气储层特征[J]. 中国煤炭地质, 2015, 27(1): 31-39.
[26]	王志刚. 涪陵页岩气勘探开发重大突破与启示[J]. 石油与天然气地质, 2015, 36(1): 1-6.
[27]	王燕, 冯明刚, 魏祥峰, 等. 涪陵气田焦石坝区块页岩气储层储集空间特征及其定量评价[J]. 海相油气地质, 2016, 21(1): 29-34.
[28]	翟刚毅, 包书景, 王玉芳, 等. 古隆起边缘成藏模式与湖北宜昌页岩气重大发现[J]. 地球学报, 2017, 38(4): 441-447.
[29]	YANG W, ZUO R S, JIANG Z X, et al. Effect of lithofacies on pore structure and new insights into pore-preserving mechanisms of the over-mature Qiongzhusi marine shales in Lower Cambrian of the southern Sichuan Basin, China[J]. Marine and Petroleum Geology, 2018, 98: 746-762. DOI URL
[30]	何晶, 何生, 刘早学, 等. 鄂西黄陵背斜南翼下寒武统水井沱组页岩孔隙结构与吸附能力[J]. 石油学报, 2020, 41(1): 27-42. DOI
[31]	胡明毅, 邓庆杰, 胡忠贵. 上扬子地区下寒武统牛蹄塘组页岩气成藏条件[J]. 石油与天然气地质, 2014, 35(2): 272-279.
[32]	刘艳杰, 程党性, 邱庆伦, 等. 南华北盆地下二叠统泥页岩孔隙特征及控制因素[J]. 天然气地球科学, 2020, 31(10): 1501-1513.
[33]	吕海刚. 四川盆地志留系龙马溪组泥页岩吸水模拟实验及对孔隙连通性的指示意义[D]. 兰州: 兰州大学, 2015.
[34]	邱小松, 胡明毅, 胡忠贵, 等. 页岩气资源评价方法及评价参数赋值: 以中扬子地区五峰组—龙马溪组为例[J]. 中国地质, 2014, 41(6): 2091-2098.
[35]	李艳霞, 林娟华, 龙幼康, 等. 中扬子地区下古生界海相泥-页岩含气勘探远景[J]. 地质通报, 2011, 30(增刊1): 349-356.
[36]	李忠雄, 陆永潮, 王剑, 等. 中扬子地区晚震旦世—早寒武世沉积特征及岩相古地理[J]. 古地理学报, 2004, 6(2): 151-162.
[37]	赵建华, 金之钧, 林畅松, 等. 上扬子地区下寒武统筇竹寺组页岩沉积环境[J]. 石油与天然气地质, 2019, 40(4): 701-715.
[38]	孙健. 黔北地区浅层龙马溪组页岩含气性及其控制因素[D]. 北京: 中国科学院大学(中国科学院广州地球化学研究所), 2020.
[39]	SHAO D Y, ELLIS G S, LI Y F, et al. Experimental investigation of the role of rock fabric in gas generation and expulsion during thermal maturation: anhydrous closed-system pyrolysis of a bitumen-rich Eagle Ford Shale[J]. Organic Geochemistry, 2018, 119: 22-35. DOI URL
[40]	沈伟军, 郭伟, 李熙喆, 等. 水蒸气吸附法和氮气吸附法在表征页岩孔隙结构中的对比分析[J]. 天然气工业, 2017, 37 (增刊1): 78-84.
[41]	郝光宗, 邢丽缘, 梁强威. 饱和盐水溶液湿度固定点(2):数据来源与盐溶液选择[J]. 传感器世界, 1999, 5(12): 10-14.
[42]	于萍, 张瑜, 闫建萍, 等. 四川盆地龙马溪组页岩吸水特征及3种页岩孔隙度分析方法对比[J]. 天然气地球科学, 2020, 31(7): 1016-1027.
[43]	CHALMERS G R, BUSTIN R M, POWER I M. Characterization of gas shale pore systems by porosimetry, pycnometry, surface area, and field emission scanning electron microscopy/transmission electron microscopy image analyses: examples from the Barnett, Woodford, Haynesville, Marcellus, and Doig units[J]. AAPG Bulletin, 2012, 96(6): 1099-1119. DOI URL
[44]	QIN M Y, CAO Z, GUO J H, et al. Characteristics of shale reservoir and sweet spot identification of the lower Cambrian Niutitang formation in northwestern Hunan Province, China[J]. Acta Geologica Sinica-English Edition, 2019, 93(3): 573-587. DOI URL
[45]	蒲泊伶, 董大忠, 耳闯, 等. 川南地区龙马溪组页岩有利储层发育特征及其影响因素[J]. 天然气工业, 2013, 33(12): 41-47.
[46]	冯东, 李相方, 王香增, 等. 不同含水条件下黏土孔隙分布特征及甲烷吸附能力[J]. 煤炭学报, 2017, 42(9): 2402-2413.
[47]	张聪. 鄂西宜昌地区下寒武统水井沱组页岩生烃潜力与储层特征研究[D]. 北京: 中国地质大学(北京), 2020.
[48]	ROSS D J K, BUSTIN R M. Characterizing the shale gas resource potential of Devonian-Mississippian strata in the Western Canada sedimentary basin: application of an integrated formation evaluation[J]. AAPG Bulletin, 2008, 92(1): 87-125. DOI URL
[49]	郭彤楼. 涪陵页岩气田发现的启示与思考[J]. 地学前缘, 2016, 23(1): 29-43. DOI
[50]	王濡岳, 丁文龙, 龚大建, 等. 黔北地区海相页岩气保存条件: 以贵州岑巩区块下寒武统牛蹄塘组为例[J]. 石油与天然气地质, 2016, 37(1): 45-55.
[51]	魏祥峰, 李宇平, 魏志红, 等. 保存条件对四川盆地及周缘海相页岩气富集高产的影响机制[J]. 石油实验地质, 2017, 39(2): 147-153.
[52]	王宁, 许锋, 王喆, 等. 上扬子地台北缘下寒武统牛蹄塘组海相页岩气地质条件及勘探潜力[J]. 地球科学与环境学报, 2020, 42(3): 329-341.
[53]	ZOU C N, YANG Z, SUN S S, et al. “Exploring petroleum inside source kitchen”: shale oil and gas in Sichuan Basin[J]. Science China Earth Sciences, 2020, 63(7): 934-953. DOI
[54]	门玉澎, 闫剑飞, 戚明辉, 等. 黔南地区下寒武统牛蹄塘组页岩气顶底板特征研究[J]. 沉积与特提斯地质, 2020, 40(1): 53-59.
[55]	付晓飞, 吴桐, 吕延防, 等. 油气藏盖层封闭性研究现状及未来发展趋势[J]. 石油与天然气地质, 2018, 39(3): 454-471.
[56]	林潼, 王孝明, 张璐, 等. 盖层厚度对天然气封闭能力的实验分析[J]. 天然气地球科学, 2019, 30(3): 322-330.
[57]	邵德勇, 张六六, 张亚军, 等. 中上扬子地区下寒武统富有机质页岩吸水特征及对页岩气勘探的指示意义[J]. 天然气地球科学, 2020, 31(7): 1004-1015.
[58]	李海, 刘安, 罗胜元, 等. 鄂西宜昌地区寒武系页岩孔隙结构特征及发育主控因素[J]. 油气地质与采收率, 2018, 25(6): 16-23.