Lithologic Reservoirs ›› 2024, Vol. 36 ›› Issue (2): 76-88.doi: 10.12108/yxyqc.20240208

• PETROLEUM EXPLORATION • Previous Articles    

Micro-pore structure characteristics of coal seams of Jurassic Yan’an Formation in Shenmu area，Ordos Basin

LI Qihui1, REN Dazhong1, NING Bo2, SUN Zhen3, LI Tian1, WAN Cixuan3, YANG Fu4, ZHANG Shiming5   

  1. 1. Engineering Research Center of Development and Management for Low to Ultra-Low Permeability Oil & Gas Reservoirs in West China, Ministry of Education, College of Petroleum Engineering, Xi'an Shiyou University, Xi'an 710065, China;
    2. PetroChina Research Institute of Petroleum Exploration & Development, Beijing 100083, China;
    3. No. 6 Gas Production Plant, PetroChina Changqing Oilfield Company, Xi'an 710018, China;
    4. Key Laboratory of Coal Resources Exploration and Comprehensive Utilization, Ministry of Natural Resources, Xi'an 710021, China;
    5. PetroChina Research Institute of Petroleum Exploration and Development-Northwest, Lanzhou 730020, China
  • Received:2022-11-12 Revised:2022-12-26 Published:2024-03-06

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Abstract: The pore structure of coal seams has a significant influence on the adsorption and diffusion of coalbedmethane. By means of gas adsorption，nuclear magnetic resonance and scanning electron microscopy，a multiscale and multi-parameter joint characterization of coal seam pore structure of Jurassic Yan’an Formation in Shenmu area of Ordos Basin was carried out to clarify the law of desorption，diffusion and seepage of coalbed methane. The results show that：（1）The coal seams of Yan’an Formation in Shenmu area have average porosity and permeability of 6.89% and 4.82 mD respectively，which belong to typical ultralow permeability coal seams， mainly developing calcite，clay minerals and amorphous components，of which the average mass fraction is 54.8%，35.7% and 15.0% respectively.（2）The main reservoir spaces of coal seams in the study area are narrow‐slit shaped and ink bottle shaped，including stomata，interchip pores，cell pores，mold pores and a few microcracks. The pores are dominated by mesoporous pores with pore size of 2-50 nm，followed by macropores，with the least amount of micropores. However，micropores are the main contributors to the specific surface area and pore volume of pores，indicating that coalbed methane is mainly adsorbed in micropores.（3）The pore throat size of coal seams in the study area varies in nano-and micron-level，the contribution to permeability mainly comes from submicron to micro pore throats，indicating that the pore connectivity in this range is good. The movable fluid saturation of coal samples is 38.72%-65.06%，the mercury removal efficiency is 0.84%-44.30%，the homogenization coefficient is 1.86-10.95，and the contribution of pore throat radius to permeability at different depths were significantly different，indicating strong heterogeneity in this area.

Key words: nuclear magnetic resonance, gas adsorption, heterogeneity, micropore, pore structure, coal seam, Yan’an Formation, Jurassic, Ordos Basin

CLC Number: 

  • TE122.2
[1] 姚艳斌,刘大锰,黄文辉,等. 两淮煤田煤储层孔-裂隙系统与煤层气产出性能研究[J]. 煤炭学报,2006,31(2):163-168. YAO Yanbin,LIU Dameng,HUANG Wenhui,et al. Research on the pore-fractures system properties of coalbed methane reservoirs and recovery in Huainan and Huaibei coal-fields[J]. Journal of China Coal Society,2006,31(2):163-168.
[2] 姚艳斌,刘大锰,蔡益栋,等. 基于NMR和X-CT的煤的孔裂隙精细定量表征[J]. 中国科学:地球科学,2010,40(11):1598-1607. YAO Yanbin,LIU Dameng,CAI Yidong,et al. Advanced characterization of pores and fractures in coals by nuclear magnetic resonance and X-ray computed tomography[J]. Scientia Sinica Terrae,2010,40(11):1598-1607.
[3] 李子文,郝志勇,庞源,等. 煤的分形维数及其对瓦斯吸附的影响[J].煤炭学报,2015,40(4):863-869. LI Ziwen,HAO Zhiyong,PANG Yuan,et al. Fractal dimensions of coal and their influence on methane adsorption[J]. Journal of China Coal Society,2015,40(4):863-869.
[4] 李子文,林柏泉,郝志勇,等. 煤体孔径分布特征及其对瓦斯吸附的影响[J]. 中国矿业大学学报,2013,42(6):1047-1053. LI Ziwen,LIN Baiquan,HAO Zhiyong,et al. Characteristics of pore size distribution of coal and its impacts on gas adsorption[J]. Journal of China University of Mining & Technology, 2013,42(6):1047-1053.
[5] 邵显华,杨昌永,常会珍. 基于压汞法的赵庄矿不同煤体结构煤的孔隙特征研究[J]. 能源与环保,2019,41(7):7-10. SHAO Xianhua,YANG Changyong,CHANG Huizhen. Study on pore characteristics with different coal body structure in Zhaozhuang coal mine based on mercury injection method[J]. China Energy and Environmental Protection,2019,41(7):7-10.
[6] 姚晋宝,郝春生,杨昌永. 基于压汞法的成庄井田3号煤孔隙特征研究[J].能源与环保,2019,41(7):1-6. YAO Jinbao,HAO Chunsheng,YANG Changyong. Study on pore characteristics of No. 3 coal seam in Chengzhuang mine field based on mercury injection method[J]. China Energy and Environmental Protection,2019,41(7):1-6.
[7] 邵龙义,李佳旭,王帅,等. 海拉尔盆地褐煤液氮吸附孔的孔隙结构及分形特征[J].天然气工业,2020,40(5):15-25. SHAO Longyi,LI Jiaxu,WANG Shuai,et al. Pore structures and fractal characteristics of liquid nitrogen adsorption pores in lignite in the Hailar Basin[J]. Natural Gas Industry,2020,40(5):15-25.
[8] 孟召平,刘珊珊,王保玉,等. 不同煤体结构煤的吸附性能及其孔隙结构特征[J]. 煤炭学报,2015,40(8):1865-1870.MENG Shaoping,LIU Shanshan,WANG Baoyu,et al. Adsorption capacity and its pore structure of coals with different coal body structure[J]. Journal of China Coal Society,2015,40(8):1865-1870.
[9] 王子萌,蒋裕强,付永红,等. 基于核磁共振表征渝西地区五峰组-龙一1亚段页岩储层孔隙结构及非均质性[J]. 地球科学,2022,47(2):490-504. WANG Zimeng,JIANG Yuqiang,FU Yonghong,et al. Characterization of pore structure and heterogeneity of shale reservoir from Wufeng Formation-sublayers Long-11 in western Chongqing based on nuclear magnetic resonance[J]. Earth Science, 2022,47(2):490-504.
[10] 谢松彬,姚艳斌,陈基瑜,等. 煤储层微小孔孔隙结构的低场核磁共振研究[J]. 煤炭学报,2015,40(增刊1):170-176. XIE Songbin,YAO Yanbin,CHEN Jiyu,et al. Research of micro-pore structure in coal reservoir using low-field NMR[J]. Journal of China Coal Society,2015,40(Suppl 1):170-176.
[11] 杨昌永,常会珍,邵显华,等. 扫描电镜下不同煤体结构煤微孔隙特征研究[J]. 煤炭科学技术,2019,47(12):194-200. YANG Changyong,CHANG Huizhen,SHAO Xianhua,et al. Study on micro-pore characteristics of structural coal in different coal bodies under scanning electron microscopy[J]. Coal Science and Technology,2019,47(12):194-200.
[12] 邹俊鹏,陈卫忠,杨典森,等. 基于SEM的珲春低阶煤微观结构特征研究[J]. 岩石力学与工程学报,2016,35(9):1805-1814. ZOU Junpeng,CHEN Weizhong,YANG Diansen,et al. Microstructural characteristics of low-rank coal from Hunchun based on SEM[J]. Chinese Journal of Rock Mechanics and Engineering,2016,35(9):1805-1814.
[13] 胥畅,王文卉,姚素平. 聚焦离子束扫描电镜研究微体化石的微观孔隙结构[J]. 高校地质学报,2016,22(1):207-212. XU Chang,WANG Wenhui,YAO Suping. A study into the microscopic pore structure of microfossils with focused ion beam scanning electron microscopy[J]. Geological Journal of China Universities,2016,22(1):207-212
[14] 杨明,柳磊,刘佳佳,等. 中阶煤孔隙结构的氮吸附-压汞-核磁共振联合表征研究[J]. 煤炭科学技术,2021,49(5):67-74. YANG Ming,LIU Lei,LIU Jiajia,et al. Study on joint characterization of pore structure of middle-rank coal by nitrogen adsorption-mercury intrusion-NMR[J]. Coal Science and Technology,2021,49(5):67-74.
[15] 李祥春,高佳星,张爽,等. 基于扫描电镜、孔隙-裂隙分析系统和气体吸附的煤孔隙结构联合表征[J]. 地球科学,2022, 47(5):1876-1889. LI Xiangchun,GAO Jiaxing,ZHANG Shuang,et al. Combined characterization of scanning electron microscopy,pore and crack analysis system,and gas adsorption on pore structure of coal with different volatilization[J]. Earth Science,2022,47(5):1876-1889.
[16] 刘怀谦,王磊,谢广祥,等. 煤体孔隙结构综合表征及全孔径分形特征[J].采矿与安全工程学报,2022,39(3):458-469. LIU Huaiqian,WANG Lei,XIE Guangxiang,et al. Comprehensive characterization and full pore size fractal characteristics of coal pore structure[J]. Journal of Mining & Safety Engineering,2022,39(3):458-469.
[17] 雷海艳,郭佩,孟颖,等. 玛湖凹陷二叠系风城组页岩油储层孔隙结构及分类评价[J]. 岩性油气藏,2022,34(3):142-153. LEI Haiyan,GUO Pei,MENG Ying,et al. Pore structure and classification evaluation of shale oil reservoirs of Permian Fengcheng Formation in Mahu Sag[J]. Lithologic Reservoirs, 2022,34(3):142-153.
[18] 刘小勤,王西强,罗顺社,等. 鄂尔多斯盆地环江地区延安组延10储层特征及主控因素分析[J]. 中国科技论文,2022,17(9):978-985. LIU Xiaoqin,WANG Xiqiang,LUO Shunshe,et al. Characteristics and its controlling factors of Yan 10 reservoir in Yan'an Formation,Huanjiang area,Ordos Basin[J]. China Sciencepaper,2022,17(9):978-985.
[19] 任大忠,周兆华,梁睿翔,等. 致密砂岩气藏黏土矿物特征及其对储层性质的影响:以鄂尔多斯盆地苏里格气田为例[J]. 岩性油气藏,2019,31(4):42-53. REN Dazhong,ZHOU Zhaohua,LIANG Ruixiang,et al. Characteristics of clay minerals and its impacts on reservoir quality of tight sandstone gas reservoir:A case from Sulige gas field, Ordos Basin[J]. Lithologic Reservoirs,2019,31(4):42-53.
[20] 蔺亚兵,贾雪梅,马东民. 基于液氮吸附法对煤的孔隙特征研究与应用[J]. 煤炭科学技术,2016,44(3):135-140. LIN Yabing,JIA Xuemei,MA Dongmin. Study and application of coal pore features based on liquid nitrogen adsorption method[J]. Coal Science and Technology,2016,44(3):135-140.
[21] 张凤奇,李宜浓,罗菊兰,等. 鄂尔多斯盆地西部奥陶系乌拉力克组页岩微观孔隙结构特征[J]. 岩性油气藏,2022,34(5):50-62. ZHANG Fengqi,LI Yinong,LUO Julan,et al. Microscopic pore structure characteristics of shale of Ordovician Wulalike Formation in western Ordos Basin[J]. Lithologic Reservoirs, 2022,34(5):50-62.
[22] 赵迪斐,郭英海,毛潇潇,等. 基于压汞、氮气吸附与FE-SEM的无烟煤微纳米孔特征[J]. 煤炭学报,2017,42(6):1517-1526. ZHAO Difei,GUO Yinghai,MAO Xiaoxiao,et al. Characteristics of macro-nanopores in anthracite coal based on mercury injection,nitrogen adsorption and FE-SEM[J]. Journal of China Coal Society,2017,42(6):1517-1526.
[23] 杨甫,贺丹,马东民,等. 低阶煤储层微观孔隙结构多尺度联合表征[J]. 岩性油气藏,2020,32(3):14-23. YANG Fu,HE Dan,MA Dongmin,et al. Multi-scale joint characterization of micro-pore structure of low-rank coal reservoir[J]. Lithologic Reservoirs,2020,32(3):14-23.
[24] 李阳,张玉贵,张浪,等. 基于压汞、低温N2吸附和CO2吸附的构造煤孔隙结构表征[J]. 煤炭学报,2019,44(4):1188-1196. LI Yang,ZHANG Yugui,ZHANG Lang,et al.Characterization on pore structure of tectonic coals based on the method of mercury intrusion,carbon dioxide adsorption and nitrogen adsorption[J]. Journal of China Coal Society,2019,44(4):1188-1196.
[25] 任会康,王安民,李昌峰,等. 基于核磁共振技术的低阶煤储层孔隙特征研究[J]. 煤炭科学技术,2017,45(4):143-148. REN Huikang,WANG Anmin,LI Changfeng,et al. Study onporosity characteristics of low-rank coal reservoirs based on nuclear magnetic resonance technology[J]. Coal Science and Technology,2017,45(4):143-148.
[26] 吴建彪,王瑞飞,杨川,等. 鄂尔多斯盆地致密砂岩气藏微观孔喉球棍模型表征方法[J]. 地球物理学进展,2023,38(1):337-347. WU Jianbiao,WANG Ruifei,YANG Chuan,et al. Micro nano pore throat CT imaging ball stick model of tight sandstone gas reservoir in Ordos Basin[J]. Progress in Geophysics,2023,38(1):337-347.
[27] 焦堃,姚素平,吴浩,等. 页岩气储层孔隙系统表征方法研究进展[J].高校地质学报,2014,20(1):151-161. JIAO Kun,YAO Suping,WU Hao,et al. Advances in characterization of pore system of gas shales[J]. Geological Journal of China Universities,2014,20(1):151-161.
[28] 曾宏斌,王芙蓉,罗京,等. 基于低温氮气吸附和高压压汞表征潜江凹陷盐间页岩油储层孔隙结构特征[J]. 地质科技通报,2021,40(5):242-252. ZENG Hongbin,WANG Furong,LUO Jing,et al. Characteristics of pore structure of intersalt shale oil reservoir by low temperature nitrogen adsorption and high pressure mercury pressure methods in Qianjiang Sag[J]. Bulletin of Geological Science and Technology,2021,40(5):242-252.
[29] 张先伟,孔令伟. 利用扫描电镜、压汞法、氮气吸附法评价近海黏土孔隙特征[J]. 岩土力学,2013,34(增刊2):134-142. ZHANG Xianwei,KONG Lingwei. Study of pore characteristics of offshore clay by SEM and MIP and NA methods[J]. Rock and Soil Mechanics,2013,34(Suppl 2):134-142.
[30] 陈居凯,朱炎铭,崔兆帮,等. 川南龙马溪组页岩孔隙结构综合表征及其分形特征[J]. 岩性油气藏,2018,30(1):55-62. CHEN Jukai,ZHU Yanming,CUI Zhaobang,et al. Pore structure and fractal characteristics of Longmaxi shale in southern Sichuan Basin[J]. Lithologic Reservoirs,2018,30(1):55-62.
[31] 张记刚,杜猛,陈超,等. 吉木萨尔凹陷二叠系芦草沟组页岩储层孔隙结构定量表征[J]. 岩性油气藏,2022,34(4):89-102. ZHANG Jigang,DU Meng,CHEN Chao,et al. Quantitative characterization of pore structure of shale reservoirs of Permian Lucaogou Formation in Jimsar Sag[J]. Lithologic Reservoirs, 2022,34(4):89-102.
[32] YAO Yanbin,LIU Dameng. Comparison of low-field NMR and mercury intrusion porosimetry in characterizing pore size distrbutions of coals[J]. Fuel,2012,95(1):152-158.
[33] YUAN Yujie,REZAEE R. Comparative porosity and pore structure assessment in shales:Measurement techniques,influencing factors and implications for reservoir characterization[J]. Energies,2019,12(11):2094-2108.
[34] 杜佳,朱光辉,李勇,等. 鄂尔多斯盆缘致密砂岩气藏勘探开发挑战与技术对策:以临兴-神府气田为例[J].天然气工业, 2022,42(1):114-124. DU Jia,ZHU Guanghui,LI Yong,et al. Exploration and development challenges and technological countermeasures for tight sandstone gas reservoirs in Ordos basin margin:A case study of Linxing-Shenfu gas field[J]. Natural Gas Industry,2022,42(1):114-124.
[35] 朱光辉,李本亮,李忠城,等. 鄂尔多斯盆地东缘非常规天然气勘探实践及发展方向:以临兴-神府气田为例[J]. 中国海上油气,2022,34(4):16-29. ZHU Guanghui,LI Benliang,LI Zhongcheng,et al. Practices and development trend of unconventional natural gas exploration in eastern margin of Ordos Basin:Taking Linxing-Shenfu gas field as an example[J]. China Offshore Oil and Gas,2022, 34(4):16-29.
[36] 任大忠,孙卫,魏虎,等. 华庆油田长81储层成岩相类型及微观孔隙结构特征[J].现代地质,2014,28(2):379-387. REN Dazhong,SUN Wei,WEI Hu,et al. Types of sandstone reservoir diagenetic facies and microscopic pore structure characteristics of Chang 81 reservoir in Huaqing Oilfield[J]. Geoscience,2014,28(2):379-387.
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