页岩中有机质孔隙非均质性的微观结构及电镜—拉曼联用研究

鲍芳; 俞凌杰; 芮晓庆; 张庆珍; 范明; 马中良

doi:10.11781/sysydz202105871

页岩中有机质孔隙非均质性的微观结构及电镜—拉曼联用研究

doi: 10.11781/sysydz202105871

鲍芳^{1, 2,},
俞凌杰^{1, 2},
芮晓庆^{1, 2},
张庆珍^{1, 2},
范明^{1, 2},
马中良^{1, 2}

1.
中国石化油气成藏重点实验室, 江苏无锡 214126
2.
中国石化石油勘探开发研究院无锡石油地质研究所, 江苏无锡 214126

基金项目:

国家自然科学基金 42072156

详细信息

作者简介:
鲍芳(1981-), 女, 博士, 高级工程师, 从事岩石矿物微区分析技术研究。E-mail: baofang.syky@sinopec.com

中图分类号: TE122.23
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- 被引次数: 0
出版历程
- 收稿日期: 2021-07-07
- 修回日期: 2021-08-29
- 刊出日期: 2021-09-28

Microstructure and SEM-Raman study of organic matter pore heterogeneity in shale

BAO Fang^{1, 2
,},
YU Lingjie^{1, 2},
RUI Xiaoqing^{1, 2},
ZHANG Qingzhen^{1, 2},
FAN Ming^{1, 2},
MA Zhongliang^{1, 2}

1.
SINOPEC Key Laboratory of Petroleum Accumulation Mechanisms, Wuxi, Jiangsu 214126, China
2.
Wuxi Research Institute of Petroleum Geology, SINOPEC, Wuxi, Jiangsu 214126, China

摘要

摘要: 页岩中有机质孔隙的发育特征及其影响因素对我国页岩气勘探开发具有重要意义。扫描电镜下观察发现页岩中有机质的孔隙发育常见非均质性，但现阶段由于缺乏有效的微区研究方法，有机质孔隙发育的影响因素仍存在较大的争议。选取四川盆地平桥地区下志留统龙马溪组黑色页岩，利用氩离子抛光-扫描电镜、FIB-SEM三维分析技术，从二维和三维层面对页岩中有机质孔隙的非均质性特征进行了分析。不依赖于有机质显微组分类型，只考虑有机质的孔隙发育程度，将不同孔隙发育程度的有机质分为3个级别，并利用大面积背散射成像（MAPS）分析方法对这三种有机质的面积占有率和对孔隙的贡献度分别进行了定量分析；采用扫描电镜-激光拉曼联用技术分析其拉曼光谱，利用拉曼参数的差别探讨了影响有机质孔隙发育非均质性的主要因素。不同孔隙发育程度有机质的D峰与G峰强度比不同，说明不同有机质的芳香结构有序度有较明显的区别，表明影响有机质孔隙发育的主要因素为原始有机质的组成。该方法能够在微区观察有机质孔隙的同时，原位分析有机质显微组分的分子结构特征，明确有机质孔隙发育的主要影响因素。
- 扫描电镜 /
- 拉曼光谱 /
- 非均质性 /
- 孔隙 /
- 有机质 /
- 页岩
Abstract: The characteristics and influencing factors of pore development in organic matters of shale are of great significance for shale gas exploration and production in China. The pore development in organic matters of shale has been found to be heterogeneous with SEM observation. However, due to the lack of effective approach for micro-scale research, the influencing factors of pore development of organic matter are still controversial. Black shale samples of the Longmaxi Formation of Pingqiao area of the Sichuan Basin were selected by this study and the heterogeneity of development and distribution of pores in organic matters were analyzed in detail from two-dimensional and three-dimensional levels by the means of Ar ion polishing SEM and FIB-SEM observation. The organic matters with different pore development degrees were divided into three levels, and the area occupancy and contribution to the pores of these three levels of organic matter were studied by MAPS. In this paper, the Raman spectrum of three levels of organic matter with different pore development were obtained by SEM-Raman. The main factors affecting the heterogeneity of pore development of organic matter were discussed in view of the differences of Raman parameters. The results showed that the intensity ratio of D peak to G peak of organic matter was different, which indicated that the order degree of aromatic structure of different organic matter was significantly different, proving that the main factor affecting the pore development in organic matter could be the composition of original organic matter. This method can be used to observe the pores of organic matter in micro area and analyze the molecular structure characteristics of organic matter macerals in-situ, and further clarifies the main influencing factors of pore development of organic matter.
- scanning electron microscope (SEM) /
- Raman spectra /
- heterogeneity /
- porosity /
- organic matter /
- shale

HTML全文

图 1 四川盆地平桥页岩气田下志留统龙马溪组页岩岩心样品中不同类型孔隙特征的扫描电镜照片

Figure 1. SEM photographs of different types of pores in core samples from Lower Silurian Longmaxi Formation, Pingqiao shale gas field, Sichuan Basin

下载: 全尺寸图片幻灯片

图 2 四川盆地平桥页岩气田下志留统龙马溪组页岩岩心样品中不同孔隙发育特征有机质的扫描电镜照片

Figure 2. SEM photographs of organic matter with different pore development in core samples from Lower Silurian Longmaxi Formation, Pingqiao shale gas field, Sichuan Basin

下载: 全尺寸图片幻灯片

图 3 四川盆地平桥页岩气田下志留统龙马溪组页岩岩心样品不同孔隙发育程度有机质的FIB-SEM三维重构图

a.一级孔隙发育有机质；b.二级孔隙发育有机质；c.三级孔隙发育有机质
1.三维重构图；2.有机质与孔隙的三维分布图；3.有机质孔隙的三维分布图；4.有机质孔隙孔径分布图

Figure 3. FIB-SEM three-dimensional reconstruction of organic matter with different pore development in core samples from Lower Silurian Longmaxi Formation, Pingqiao shale gas field, Sichuan Basin

下载: 全尺寸图片幻灯片

图 4 四川盆地平桥页岩气田下志留统龙马溪组页岩岩心样品不同孔隙发育程度有机质的MAPS分析

Figure 4. MAPS analysis of organic matter with different pore development in core samples from Lower Silurian Longmaxi Formation, Pingqiao shale gas field, Sichuan Basin

下载: 全尺寸图片幻灯片

图 5 四川盆地平桥页岩气田下志留统龙马溪组页岩岩心样品不同孔隙发育程度有机质的拉曼光谱图

Figure 5. Raman spectra of organic matter with different pore development in core samples from Lower Silurian Longmaxi Formation, Pingqiao shale gas field, Sichuan Basin

下载: 全尺寸图片幻灯片

图 6 不同孔隙发育程度有机质的峰强度比(D/G)分布

Figure 6. Peak intensity ratio (D/G) of organic matter with different pore development degrees

下载: 全尺寸图片幻灯片

图 7 四川盆地平桥页岩气田下志留统龙马溪组页岩岩心样品孔隙发育不均匀有机质颗粒的扫描电镜图

Figure 7. SEM photographs of organic matter with uneven pore development in core samples from Lower Silurian Longmaxi Formation, Pingqiao shale gas field, Sichuan Basin

下载: 全尺寸图片幻灯片

图 8 四川盆地平桥页岩气田下志留统龙马溪组页岩岩心样品孔隙发育不均匀有机质颗粒的拉曼面分布

Figure 8. Raman surface distribution of organic matter with uneven pore development in core samples from Lower Silurian Longmaxi Formation, Pingqiao shale gas field, Sichuan Basin

下载: 全尺寸图片幻灯片

表 1 四川盆地平桥页岩气田下志留统龙马溪组页岩岩心样品不同孔隙发育等级有机质的参数

Table 1. Parameters of organic matter with different pore development in core samples from Lower Silurian Longmaxi Formation, Pingqiao shale gas field, Sichuan Basin

有机质孔隙发育等级	有机质孔隙度/%	主要孔径/nm	有机质面积占有率/%	对有机质孔隙度的贡献率/%
一级	＜1	＜30	2.96	0.32
二级	1~5	50~200	9.09	5.47
三级	＞5	10~50	87.95	94.2

下载: 导出CSV

表 2 四川盆地平桥页岩气田下志留统龙马溪组页岩岩心样品不同孔隙发育程度有机质的拉曼光谱主要参数

Table 2. Raman parameters of organic matter with different pore development in core samples from Lower Silurian Longmaxi Formation, Pingqiao shale gas field, Sichuan Basin

有机质等级	拉曼位移(D)/cm^-1	拉曼位移(G)/cm^-1	峰强度(D)	峰强度(G)	位移差(G-D) /cm^-1	峰强度比(D/G)
一级	1 334.55	1 598.66	1 924.65	2 989.03	264.11	0.64
	1 334.49	1 591.04	1 476.41	2 338.54	256.55	0.63
	1 336.88	1 590.74	1 412.40	2 440.46	253.86	0.58
	1 335.68	1 587.40	1 741.07	2 995.10	251.72	0.58
	1 331.32	1 586.21	3 205.41	5 497.34	254.89	0.58
二级	1 329.34	1 578.43	503.47	604.30	249.09	0.83
	1 330.87	1 584.22	810.34	934.69	253.35	0.87
	1 331.07	1 580.11	535.46	602.32	249.04	0.89
	1 332.09	1 580.84	426.77	504.77	248.75	0.85
	1 333.85	1 562.69	246.02	301.29	228.84	0.82
三级	1 323.37	1 569.11	259.55	238.14	245.74	1.09
	1 329.39	1 579.27	422.78	425.96	249.88	0.99
	1 326.28	1 571.22	396.95	393.02	244.94	1.01
	1 331.25	1 580.72	691.97	680.96	249.47	1.02
	1 342.30	1 580.34	266.25	266.57	238.04	1.00

下载: 导出CSV

参考文献(31)

[1]	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: 10.1306/08171111061
[2]	郭旭升, 李宇平, 刘若冰, 等. 四川盆地焦石坝地区龙马溪组页岩微观孔隙结构特征及其控制因素[J]. 天然气工业, 2014, 34(6): 9-16. https://www.cnki.com.cn/Article/CJFDTOTAL-TRQG201406002.htm GUO Xusheng, LI Yuping, LIU Ruobing, et al. Characteristics and controlling factors of micro-pore structures of Longmaxi shale play in the Jiaoshiba area, Sichuan Basin[J]. Natural Gas Industry, 2014, 34(6): 9-16. https://www.cnki.com.cn/Article/CJFDTOTAL-TRQG201406002.htm
[3]	邹才能, 杨智, 陶士振, 等. 纳米油气与源储共生型油气聚集[J]. 石油勘探与开发, 2012, 39(1): 13-26. https://www.cnki.com.cn/Article/CJFDTOTAL-SKYK201201003.htm ZOU Caineng, YANG Zhi, TAO Shizhen, et al. Nano-hydrocarbon and the accumulation in coexisting source and reservoir[J]. Petroleum Exploration and Development, 2012, 39(1): 13-26. https://www.cnki.com.cn/Article/CJFDTOTAL-SKYK201201003.htm
[4]	仰云峰, 鲍芳, 腾格尔, 等. 四川盆地不同成熟度下志留统龙马溪组页岩有机孔特征[J]. 石油实验地质, 2020, 42(3): 387-397. doi: 10.11781/sysydz202003387 YANG Yunfeng, BAO Fang, BORJIGIN Tenger, et al. Characteristics of organic matter-hosted pores in Lower Silurian Longmaxi shale with different maturities, Sichuan Basin[J]. Petroleum Geo-logy & Experiment, 2020, 42(3): 387-397. doi: 10.11781/sysydz202003387
[5]	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: 10.2110/jsr.2009.092
[6]	CURTIS M E. Structural characterization of gas shales on the micro- and nano-scales[C]//Paper presented at the Canadian Unconventional Resources and International Petroleum Conference. Calgary: SPE, 2010.
[7]	SONDERGELD C H, AMBROSE R J, RAI C S, et al. Micro-structural studies of gas shales[C]//SPE Unconventional Gas Conference. Pittsburgh: SPE, 2010.
[8]	KELLY S, EL-SOBKY H, TORRES-VERD'IN C, et al. Assessing the utility of FIB-SEM images for shale digital rock physics[J]. Advances in Water Resources, 2016, 95: 302-316. doi: 10.1016/j.advwatres.2015.06.010
[9]	曾庆辉, 钱玲, 刘德汉, 等. 富有机质的黑色页岩和油页岩的有机岩石学特征与生、排烃意义[J]. 沉积学报, 2006, 24(1): 113-122. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB200601014.htm ZENG Qinghui, QIAN Lin, LIU Dehan, et al. Organic petrological study on hydrocarbon generation and expulsion from organic-rich black shale and oil shale[J]. Acta Sedimentologica Sinica, 2006, 24(1): 113-122. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB200601014.htm
[10]	张慧, 焦淑静, 庞起发, 等. 中国南方早古生代页岩有机质的扫描电镜研究[J]. 石油与天然气地质, 2015, 36(4): 675-680. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT201504019.htm ZHANG Hui, JIAO Shujing, PANG Qifa, et al. SEM observation of organic matters in the Eopaleozoic shale in South China[J]. Oil & Gas Geology, 2015, 36(4): 675-680. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT201504019.htm
[11]	董晓霞, 熊亮. 川南筇竹寺组页岩储集空间类型及发育影响因素[J]. 物探化探计算技术, 2016, 38(3): 415-422. https://www.cnki.com.cn/Article/CJFDTOTAL-WTHT201603019.htm DONG Xiaoxia, XIONG Liang. Microscopic space types and its influencing factors of the Lower Cambrian Qiongzhusi shale, southern Sichuan Basin[J]. Computing Techniques for Geophy-sical and Geochemical Exploration, 2016, 38(3): 415-422. https://www.cnki.com.cn/Article/CJFDTOTAL-WTHT201603019.htm
[12]	郭旭升, 胡东风, 黄仁春, 等. 四川盆地深层-超深层天然气勘探进展与展望[J]. 天然气工业, 2020, 40(5): 1-14. https://www.cnki.com.cn/Article/CJFDTOTAL-TRQG202005002.htm GUO Xusheng, HU Dongfeng, HUANG Renchun, et al. Deep and ultra-deep natural gas exploration in the Sichuan Basin: progress and prospect[J]. Natural Gas Industry, 2020, 40(5): 1-14. https://www.cnki.com.cn/Article/CJFDTOTAL-TRQG202005002.htm
[13]	MILLIKEN K L, RUDNICKI M, AWWILLER D N, et al. Organic matter-hosted pore system, Marcellus Formation (Devonian), Pennsylvania[J]. AAPG Bulletin, 2013, 97(2): 177-200. doi: 10.1306/07231212048
[14]	宋董军, 妥进才, 王晔桐, 等. 富有机质泥页岩纳米级孔隙结构特征研究进展[J]. 沉积学报, 2019, 37(6): 1309-1324. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB201906018.htm SONG Dongjun, TUO Jincai, WANG Yetong, et al. Research advances on characteristics of nanopore structure of organic-rich shales[J]. Acta Sedimentologica Sinica, 2019, 37(6): 1309-1324. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB201906018.htm
[15]	POTGIETER-VERMAAK S, MALEDI N, WAGNER N, et al. Raman spectroscopy for the analysis of coal: a review[J]. Journal of Raman Spectroscopy, 2011, 42(2): 123-129. doi: 10.1002/jrs.2636
[16]	SCHOPF J W, KUDRYAVTSEV A B, AGRESTI D G, et al. Laser-Raman imagery of Earth's earliest fossils[J]. Nature, 2002, 416(6876): 73-76. doi: 10.1038/416073a
[17]	KELEMEN S R, FANG H L. Maturity trends in Raman spectra from kerogen and coal[J]. Energy & Fuels, 2001, 15(3): 653-658.
[18]	刘德汉, 肖贤明, 田辉, 等. 固体有机质拉曼光谱参数计算样品热演化程度的方法与地质应用[J]. 科学通报, 2013, 58(13): 1228-1241. https://www.cnki.com.cn/Article/CJFDTOTAL-KXTB201313010.htm LIU Dehan, XIAO Xianming, TIAN Hui, et al. Sample maturation calculated using Raman spectroscopic parameters for solid organics: methodology and geological applications[J]. Chinese Science Bulletin, 2013, 58(11): 1285-1298. https://www.cnki.com.cn/Article/CJFDTOTAL-KXTB201313010.htm
[19]	鲍芳, 腾格尔, 仰云峰, 等. 不同成烃生物的拉曼光谱特征[J]. 高校地质学报, 2012, 18(1): 174-179. https://www.cnki.com.cn/Article/CJFDTOTAL-GXDX201201018.htm BAO Fang, TENGGER, YANG Yunfeng, et al. Raman spectroscopic characteristics of different hydrocarbon-forming organisms[J]. Geological Journal of China Universities, 2012, 18(1): 174-179. https://www.cnki.com.cn/Article/CJFDTOTAL-GXDX201201018.htm
[20]	WILLE G, BOURRAT X, MAUBEC N, et al. Raman-in-SEM, a multimodal and multiscale analytical tool: performance for materials and expertise[J]. Micron, 2014, 67: 50-64.
[21]	CARDELL C, GUERRA I. An overview of emerging hyphenated SEM-EDX and Raman spectroscopy systems: applications in life, environmental and materials sciences[J]. TrAC Trends in Analytical Chemistry, 2016, 77: 156-166.
[22]	胡鑫蒙, 苏文, 原江燕, 等. 扫描电镜-拉曼光谱联机系统在地球科学中的应用[J]. 矿物岩石地球化学通报, 2020, 39(6): 1095-1107. https://www.cnki.com.cn/Article/CJFDTOTAL-KYDH202006005.htm HU Xinmeng, SU Wen, YUAN Jiangyan, et al. Application of the Raman imaging and scanning electron microscopy system in earth sciences[J]. Bulletin of Mineralogy, Petrology and Geochemistry, 2020, 39(6): 1095-1107. https://www.cnki.com.cn/Article/CJFDTOTAL-KYDH202006005.htm
[23]	张聪, 夏响华, 杨玉茹, 等. 安页1井志留系龙马溪组页岩有机质拉曼光谱特征及其地质意义[J]. 岩矿测试, 2019, 38(1): 26-34. https://www.cnki.com.cn/Article/CJFDTOTAL-YKCS201901003.htm ZHANG Cong, XIA Xianghua, YANG Yuru, et al. Raman spectrum characteristics of organic matter in Silurian Longmaxi Formation shale of well Anye-1 and its geological significance[J]. Rock and Mineral Analysis, 2019, 38(1): 26-34. https://www.cnki.com.cn/Article/CJFDTOTAL-YKCS201901003.htm
[24]	郭旭升. 四川盆地涪陵平桥页岩气田五峰组-龙马溪组页岩气富集主控因素[J]. 天然气地球科学, 2019, 30(1): 1-10. https://www.cnki.com.cn/Article/CJFDTOTAL-TDKX201901001.htm GUO Xusheng. Controlling factors on shale gas accumulations of Wufeng-Longmaxi formations in Pingqiao shale gas field in Fuling area, Sichuan Basin[J]. Natural Gas Geoscience, 2019, 30(1): 1-10. https://www.cnki.com.cn/Article/CJFDTOTAL-TDKX201901001.htm
[25]	赵迪斐, 郭英海, 朱炎铭, 等. 海相页岩储层微观孔隙非均质性及其量化表征[J]. 中国矿业大学学报, 2018, 47(2): 296-307. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD201802011.htm ZHAO Difei, GUO Yinghai, ZHU Yanming, et al. Analysis of micro-scale heterogeneity characteristics in marine shale gas reservoir: pore heterogeneity and its quantitative characterization[J]. Journal of China University of Mining & Technology, 2018, 47(2): 296-307. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD201802011.htm
[26]	王晓琦, 翟增强, 金旭, 等. 地层条件下页岩有机质孔隙内CO₂与CH₄竞争吸附的分子模拟[J]. 石油勘探与开发, 2016, 43(5): 772-779. https://www.cnki.com.cn/Article/CJFDTOTAL-SKYK201605014.htm WANG Xiaoqi, ZHAI Zengqiang, JIN Xu, et al. Molecular simulation of CO₂/CH₄ competitive adsorption in organic matter pores in shale under certain geological conditions[J]. Petroleum Exploration and Development, 2016, 43(5): 772-779. https://www.cnki.com.cn/Article/CJFDTOTAL-SKYK201605014.htm
[27]	何谋春, 吕新彪, 刘艳荣. 激光拉曼光谱在油气勘探中的应用研究初探[J]. 光谱学与光谱分析, 2004, 24(11): 1363-1366. https://www.cnki.com.cn/Article/CJFDTOTAL-GUAN200411022.htm HE Mouchun, LÜ Xinbiao, LIU Yanrong. Elementary investigation on the application of laser Raman microprobe in petroleum exploration[J]. Spectroscopy and Spectral Analysis, 2004, 24(11): 1363-1366. https://www.cnki.com.cn/Article/CJFDTOTAL-GUAN200411022.htm
[28]	JEHLIC'KA J, URBAN O, POKORNY' J. Raman spectroscopy of carbon and solid bitumens in sedimentary and metamorphic rocks[J]. Spectrochimica Acta Part A: Molecular and Biomole-cular Spectroscopy, 2003, 59(10): 2341-2352.
[29]	郑辙, 陈宣华. 煤基石墨的Raman光谱研究[J]. 中国科学(B辑), 1994, 24(6): 640-647. https://www.cnki.com.cn/Article/CJFDTOTAL-JBXK199406012.htm ZHENG Zhe, CHEN Xuanhua. Raman spectrum of coal-based graphite[J]. Science in China (Series B), 1994, 24(6): 640-647. https://www.cnki.com.cn/Article/CJFDTOTAL-JBXK199406012.htm
[30]	LI Can, STAIR P C. Ultraviolet Raman spectroscopy characte-rization of coke formation in zeolites[J]. Catalysis Today, 1997, 33(1/3): 353-360.
[31]	李东风, 王浩静, 王心葵. PAN基碳纤维在石墨化过程中的拉曼光谱[J]. 光谱学与光谱分析, 2007, 27(11): 2249-2253. https://www.cnki.com.cn/Article/CJFDTOTAL-GUAN200711026.htm LI Dongfeng, WANG Haojing, WANG Xinkui. Raman spectra of PAN-based carbon fibers during graphitization[J]. Spectroscopy and Spectral Analysis, 2007, 27(11): 2249-2253. https://www.cnki.com.cn/Article/CJFDTOTAL-GUAN200711026.htm