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Gas Adsorption Characterization of Pore Structure of Organic-rich Shale: Insights into Contribution of Organic Matter to Shale Pore Network

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Abstract

Organic matter (OM)-hosted pores are the most prevalent pores in organic-rich shale, in which shale gas is generated and stored. Ascertaining the pore structure of OM and its contribution to the shale pore network provides guidance for understanding deeply the complex pore network, as well as the shale gas flow and storage mechanisms. In this study, the pore structure and heterogeneity of Wufeng–Longmaxi shales and the corresponding isolated OM samples were studied comparatively by scanning electron microscopy (SEM) observations and gas (CO2 and N2) physisorption quantification. The Wufeng–Longmaxi shales are rich in OM, with total organic carbon (TOC) contents of 1.48–3.59 wt.%. The SEM-observed microscopic pores were primarily OM-hosted pores and intra-particle pores within clays. Compared to the pore structure per gram of bulk shale, that of isolated OM showed a significantly larger micropore (d < 2 nm) volume and specific surface area (SSA), meso-pore (d = 2–50 nm) and fine macro-pore (50 < d ≤ 80 nm) volume, and Brunauer–Emmett–Teller SSA. Moreover, the pore structure heterogeneity of the bulk shale was much stronger than that of the isolated OM, revealing that pores associated with minerals could enhance the heterogeneity of shale to some extent. The pore size distributions of the bulk shale (1 g) and the corresponding weight-normalized isolated OM (1 g × TOC) were compared. It was revealed that shale pores with diameters smaller than 20 nm were provided by OM together with minerals, while almost all pores with diameters of 20–80 nm occurred within the OM. Overall, the OM and OM-hosted pores provide a vital contribution to the entire pore network of the Wufeng–Longmaxi shale.

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modified from Dai et al. (2014), Zhao et al. (2017))

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References

  • Bernard, S., Wirth, R., Schreiber, A., Schulz, H. M., & Horsfield, B. (2012). Formation of nanoporous pyrobitumen residues during maturation of the Barnett Shale (Fort Worth Basin). International Journal of Coal Geology, 103, 3–11.

    Article  Google Scholar 

  • Cao, T. T., Song, Z. G., Wang, S. B., & Xia, J. (2015). A comparative study of the specific surface area and pore structure of different shales and their kerogens. Science China-Earth Sciences, 58, 510–522.

    Article  Google Scholar 

  • Chen, Y. Y., Zou, C. N., Mastalerz, M., Zhu, R. K., Bai, B., & Yang, Z. (2015). Porosity and fractal characteristics of shale across a maturation gradient. Natural Gas Geoscience, 26, 1646–1656. (in Chinese with English abstract).

    Google Scholar 

  • Curtis, J. B. (2002). Fractured shale-gas systems. AAPG Bulletin, 86, 1921–1938.

    Google Scholar 

  • Curtis, M. E., Cardott, B. J., Sondergeld, C. H., & Rai, C. S. (2012). Development of organic porosity in the Woodford Shale with increasing thermal maturity. International Journal of Coal Geology, 103, 26–31.

    Article  Google Scholar 

  • Dai, J. X., Zou, C. N., Liao, S. M., Dong, D. Z., Ni, Y. Y., Huang, J. L., et al. (2014). Geochemistry of the extremely high thermal maturity Longmaxi shale gas, southern Sichuan Basin. Organic Geochemistry, 74, 3–12.

    Article  Google Scholar 

  • Dong, T., Harris, N. B., Ayranci, K., Twemlow, C. E., & Nassichuk, B. R. (2017a). The impact of composition on pore throat size and permeability in high maturity shales: Middle and Upper Devonian Horn River Group, northeastern British Columbia, Canada. Marine and petroleum geology, 81, 220–236.

    Article  Google Scholar 

  • Dong, T., Harris, N. B., Ayranci, K., & Yang, S. (2017b). The impact of rock composition on geomechanical properties of a shale formation: Middle and Upper Devonian Horn River Group shale, northeast British Columbia, Canada. AAPG Bulletin, 101, 177–204.

    Article  Google Scholar 

  • Dou, W. C., Liu, L. F., Wu, K. J., Xu, Z. J., & Feng, X. (2018). Diagenesis of tight oil sand reservoirs: Upper Triassic tight sandstones of Yanchang Formation in Ordos Basin, China. Geological Journal, 53, 707–724.

    Article  Google Scholar 

  • Gasparik, M., Bertier, P., Gensterblum, Y., Ghanizadeh, A., Krooss, B. M., & Littke, R. (2014). Geological controls on the methane storage capacity in organic-rich shales. International Journal of Coal Geology, 123, 34–51.

    Article  Google Scholar 

  • Habina, I., Radzik, N., Topór, T., & Krzyzak, A. T. (2017). Insight into oil and gas-shales compounds signatures in low field H-1 NMR and its application in porosity evaluation. Microporous and Mesoporous Materials, 252, 37–49.

    Article  Google Scholar 

  • Hu, R. N., Tan, J. Q., Dick, J., Li, L., & Wang, W. H. (2020). Quantification of the influences of radiolarian fossils on the pore structure of Wufeng-Lungmaxi gas shales (Ordovician-Silurian) in the Sichuan Basin, South China. Journal of Natural Gas Science and Engineering, 81, 103442.

    Article  Google Scholar 

  • Huang, H. X., Li, R. X., Jiang, Z. X., Li, J., & Chen, L. (2020a). Investigation of variation in shale gas adsorption capacity with burial depth: Insights from the adsorption potential theory. Journal of Natural Gas Science and Engineering, 73, 103043.

    Article  Google Scholar 

  • Huang, H. X., Li, R. X., Xiong, F. Y., Hu, H., Sun, W., Jiang, Z. X., et al. (2020b). A method to probe the pore-throat structure of tight reservoirs based on low-field NMR: Insights from a cylindrical pore model. Marine and Petroleum Geology, 117, 104344.

    Article  Google Scholar 

  • Javadpour, F., Fisher, D., & Unsworth, M. (2007). Nanoscale gas flow in shale gas sediments. Journal of Canadian Petroleum Technology, 46, 55–61.

    Article  Google Scholar 

  • Ji, W. M., Song, Y., Rui, Z. H., Meng, M. M., & Huang, H. X. (2017). Pore characterization of isolated organic matter from high matured gas shale reservoir. International Journal of Coal Geology, 174, 31–40.

    Article  Google Scholar 

  • Ko, L. T., Loucks, R. G., Zhang, T. W., Ruppel, S. C., & Shao, D. Y. (2016). Pore and pore network evolution of Upper Cretaceous Boquillas (Eagle Ford-equivalent) mudrocks: Results from gold tube pyrolysis experiments. AAPG Bulletin, 100, 1693–1722.

    Article  Google Scholar 

  • Ko, L. T., Ruppel, S. C., Loucks, R. G., Hackley, P. C., Zhang, T. W., & Shao, D. Y. (2018). Pore-types and pore-network evolution in Upper Devonian-Lower Mississippian Woodford and Mississippian Barnett mudstones: Insights from laboratory thermal maturation and organic petrology. International Journal of Coal Geology, 190, 3–28.

    Article  Google Scholar 

  • Kuila, U., Mccarty, D. K., Derkowski, A., Fischer, T. B., Topór, T., & Prasad, M. (2014). Nano-scale texture and porosity of organic matter and clay minerals in organic-rich mudrocks. Fuel, 135, 359–373.

    Article  Google Scholar 

  • Liu, K. Q., Ostadhassan, M., Zou, J., Gentzis, T., Rezaee, R., Buhach, B., & Carvajal-Ortiz, H. (2018b). Nanopore structures of isolated kerogen and bulk shale in Bakken Formation. Fuel, 226, 441–453.

    Article  Google Scholar 

  • Liu, K. Q., Ostadhassan, M., Zou, J., Gentzis, T., Rezaee, R., Buhach, B., & Carvajal-Ortiz, H. (2018c). Multifractal analysis of gas adsorption isotherms for pore structure characterization of the Bakken Shale. Fuel, 219, 296–311.

    Article  Google Scholar 

  • Liu, L. F., Wang, Y., Chen, Y. T., Shen, B. J., & Gao, X. Y. (2018a). Gas occurrence and accumulation characteristics of Cambrian-Ordovician shales in the Tarim Basin, northwest China. Acta Geologica Sinica (English Edition), 92, 1948–1958.

    Article  Google Scholar 

  • Loucks, R. G., Reed, R. M., Ruppel, S. C., & Hammes, U. (2012). Spectrum of pore types and networks in mudrocks and a descriptive classification for matrix-related mudrock pores. AAPG Bulletin, 96, 1071–1098.

    Article  Google Scholar 

  • Loucks, R. G., Reed, R. M., Ruppel, S. C., & Jarvie, D. M. (2009). Morphology, genesis, and distribution of nanometer-scale pores in siliceous mudstones of the Mississippian Barnett shale. Journal of Sedimentary Research, 79, 848–861.

    Article  Google Scholar 

  • Luo, Q. Y., Hao, J. Y., Skovsted, C. B., Luo, P., Khan, I., Wu, J., & Zhong, N. N. (2017). The organic petrology of graptolites and maturity assessment of the Wufeng-Longmaxi Formations from Chongqing, China: Insights from reflectance cross-ploss analysis. International Journal of Coal Geology, 183, 161–173.

    Article  Google Scholar 

  • Luo, Q. Y., Hao, J. Y., Skovsted, C. B., Xu, Y. H., Liu, Y., Wu, J., et al. (2018). Optical characteristics of graptolite-bearing sediments and its implication for thermal maturity assessment. International Journal of Coal Geology, 195, 386–401.

    Article  Google Scholar 

  • Mastalerz, M., He, L. L., Melnichenko, Y. B., & Rupp, J. A. (2012). Porosity of coal and shale: Insights from gas adsorption and SANS/USANS techniques. Energy & Fuel, 26, 5109–5120.

    Article  Google Scholar 

  • Mastalerz, M., Schimmelmann, A., Drobniak, A., & Chen, Y. Y. (2013). Porosity of Devonian and Mississippian New Albany shale across a maturation gradient: Insights from organic petrology, gas adsorption, and mercury intrusion. AAPG Bulletin, 97, 1621–1643.

    Article  Google Scholar 

  • Milliken, K. L., Rudnicki, M., Awwiller, D. N., & Zhang, T. W. (2013). Organic matter-hosted pore system, Marcellus Formation (Devonian), Pennsylvania. AAPG Bulletin, 97, 177–200.

    Article  Google Scholar 

  • Mishra, S., Mendhe, V. A., Varma, A. K., Kamble, A. D., Sharma, S., Bannerjee, M., & Kalpana, M. S. (2018). Influence of organic and inorganic content on fractal dimensions of Barakar and Barren Measures shale gas reservoirs of Raniganj Basin, India. Journal of Natural Gas Science and Engineering, 49, 393–409.

    Article  Google Scholar 

  • Pommer, M., & Milliken, K. (2015). Pore types and pore-size distributions across thermal maturity, Eagle Ford Formation, southern Texas. AAPG Bulletin, 99, 1713–1744.

    Article  Google Scholar 

  • Psarras, P., Holmes, R., Vishal, V., & Wilcox, J. (2017). Methane and CO2 adsorption capacities of kerogen in the Eagle Ford shale from molecular simulation. Accounts of Chemical Research, 50, 1818–1828.

    Article  Google Scholar 

  • Rexer, T. F., Mathia, E. J., Aplin, A. C., & Thomas, K. M. (2014). High-pressure methane adsorption and characterization of pores in Posidonia shales and isolated kerogens. Energy & Fuel, 28, 2886–2901.

    Article  Google Scholar 

  • Ross, D. J. K., & Bustin, R. M. (2009). The importance of shale composition and pore structure upon gas storage potential of shale gas reservoirs. Marine and Petroleum Geology, 26, 916–927.

    Article  Google Scholar 

  • Schoenherr, J., Littke, R., Urai, J. L., Kukla, P. A., & Rawahi, Z. (2007). Polyphase thermal evolution in the Infra-Cambrian Ara Group (south Oman Salt Basin) as deduced by maturity of solid reservoir bitumen. Organic Geochemistry, 38, 1293–1318.

    Article  Google Scholar 

  • Sun, M. D., Yu, B. S., Hu, Q. H., Zhang, Y. F., Li, B., Yang, R., et al. (2017). Pore characteristics of Longmaxi shale gas reservoir in the northwest of Guizhou, China: Investigations using small-angle neutron scattering (SANS), helium pycnometry, and gas sorption isotherm. International Journal of Coal Geology, 171, 61–68.

    Article  Google Scholar 

  • Tan, J. Q., Hu, R. N., Wang, W. H., & Dick, J. (2020). Palynological analysis of the late Ordovician-early Silurian black shales in South China provides new insights for the investigation of pore systems in shale gas reservoirs. Marine and Petroleum Geology, 116, 104145.

    Article  Google Scholar 

  • Tang, L., Song, Y., Li, Q. W., Pang, X. Q., Jiang, Z. X., Li, Z., et al. (2019). A quantitative evaluation of shale gas content in different occurrence states of the Longmaxi Formation: A new insight from Well JY-A in the Fuling shale gas field, Sichuan Basin. Acta Geologica Sinica (English Edition), 93, 400–419.

    Article  Google Scholar 

  • Tang, X. L., Jiang, Z. X., Jiang, S., & Li, Z. (2016). Heterogeneous nanoporosity of the Silurian Longmaxi Formation shale gas reservoir in the Sichuan Basin using the QEMSCAN, FIB-SEM, and nano-CT methods. Marine and Petroleum Geology, 78, 99–109.

    Article  Google Scholar 

  • Thommes, M., Kaneko, K., Neimark, A. V., Olivier, J. P., Rodriguez-Reinoso, F., Rouquerol, J., & Sing, K. S. W. (2015). Physisorption of gases, with special reference to the evaluation of surface area and pore size distribution (IUPAC Technical Report). Pure and Applied Chemistry, 87, 1051–1069.

    Article  Google Scholar 

  • Tian, H., Li, T. F., Zhang, T. W., & Xiao, X. M. (2016). Characterization of methane adsorption on overmature Lower Silurian-Upper Ordovician shales in Sichuan Basin, southwest China: Experimental results and geological implications. International Journal of Coal Geology, 156, 36–49.

    Article  Google Scholar 

  • Topór, T., Derkowski, A., Ziemiański, P., Szczurowski, J., & Mccarty, D. K. (2017). The effect of organic matter maturation and porosity evolution on methane storage potential in the Baltic Basin (Poland) shale-gas reservoir. International Journal of Coal Geology, 180, 46–56.

    Article  Google Scholar 

  • Wang, Y., Liu, L. F., & Cheng, H. (2020a). Pore structure of Triassic Yanchang mudstone, Ordos Basin: Insights into the impact of solvent extraction on porosity in lacustrine mudstone within the oil window. Journal of Petroleum Science and Engineering, 195, 107944.

    Article  Google Scholar 

  • Wang, Y., Liu, L. F., Hu, Q. H., Hao, L. W., Wang, X. M., & Sheng, Y. (2020b). Nanoscale pore network evolution of Xiamaling marine shale during organic matter maturation by hydrous pyrolysis. Energy & Fuels, 34, 1548–1563.

    Article  Google Scholar 

  • Wang, Y., Liu, L. F., Li, S. T., Ji, H. T., Xu, Z. J., Luo, Z. H., et al. (2017). The forming mechanism and process of tight oil sand reservoirs: A case study of Chang 8 oil layers of the Upper Triassic Yanchang Formation in the western Jiyuan area of the Ordos Basin, China. Journal of Petroleum Science and Engineering, 158, 29–46.

    Article  Google Scholar 

  • Wang, Y., Liu, L. F., Sheng, Y., Wang, X. M., Zheng, S. S., & Luo, Z. H. (2019a). Investigation of supercritical methane adsorption of overmature shale in Wufeng-Longmaxi Formation, southern Sichuan Basin, China. Energy & Fuels, 33, 2078–2089.

    Article  Google Scholar 

  • Wang, Y., Liu, L. F., Zheng, S. S., Luo, Z. H., Sheng, Y., & Wang, X. M. (2019b). Full-scale pore structure and its controlling factors of the Wufeng-Longmaxi shale, southern Sichuan Basin, China: Implications for pore evolution of highly overmature marine shale. Journal of Natural Gas Science and Engineering, 67, 134–146.

    Article  Google Scholar 

  • Wang, Y., Zhu, Y. M., Liu, S. M., & Zhang, R. (2016). Pore characterization and its impact on methane adsorption capacity for organic-rich marine shales. Fuel, 181, 227–237.

    Article  Google Scholar 

  • Wei, M. M., Zhang, L., Xiong, Y. Q., Li, J. H., & Peng, P. A. (2016). Nanopore structure characterization for organic-rich shale using the non-local-density functional theory by a combination of N2 and CO2 adsorption. Microporous and Mesoporous Materials, 227, 88–94.

    Article  Google Scholar 

  • Xiong, F. Y., Jiang, Z. X., Li, P., Wang, X. Z., Bi, H., Li, Y. R., et al. (2017). Pore structure of transitional shales in the Ordos Basin, NW China: Effects of composition on gas storage capacity. Fuel, 206, 504–515.

    Article  Google Scholar 

  • Yang, C., Zhang, J. C., Tang, X., Ding, J. H., Zhao, Q. R., Dang, W., et al. (2017). Comparative study on micro-pore structure of marine, terrestrial, and transitional shales in key areas, China. International Journal of Coal Geology, 171, 76–92.

    Article  Google Scholar 

  • Yang, R., He, S., Yi, J. Z., & Hu, Q. H. (2016). Nnao-scale pore structure and fractal dimension of organic-rich Wufeng-Longmaxi shale from Jiaoshiba area, Sichuan Basin: Investigations using FE-SEM, gas adsorption and helium pycnometry. Marine and Petroleum Geology, 70I, 27–45.

    Article  Google Scholar 

  • Yao, Y. B., Liu, D. M., Tang, D. Z., Tang, S. H., & Huang, W. H. (2008). Fractal characterization of adsorption-pores of coals from North China: An investigation on CH4 adsorption capacity of coals. International Journal of Coal Geology, 73, 27–42.

    Article  Google Scholar 

  • Zhang, J. Z., Li, X. Q., Xie, Z. Y., Li, J., Zhang, X. Q., Sun, K. X., & Wang, F. Y. (2018). Characterization of microscopic pore types and structures in marine shale: Examples from the Upper Permian Dalong Formation, northern Sichuan Basin, south China. Journal of Natural Gas Science and Engineering, 59, 326–342.

    Article  Google Scholar 

  • Zhang, L., Xiong, Y. Q., Li, Y., Wei, M. M., Jiang, W. M., Lei, R., & Wu, Z. Y. (2017). DFT modeling of CO2 and Ar low-pressure adsorption for accurate nanopore structure characterization in organic-rich shales. Fuel, 204, 1–11.

    Article  Google Scholar 

  • Zhang, Y. F., Yu, B. S., Pan, Z. J., Hou, C. H., Zuo, Q. W., & Sun, M. D. (2020). Effect of thermal maturity on shale pore structure: A combined study using extracted organic matter and bulk shale from Sichuan Basin, China. Journal of Natural Gas Science and Engineering, 74, 103089.

    Article  Google Scholar 

  • Zhao, J. H., Jin, Z. J., Jin, Z. K., Hu, Q. H., Hu, Z. Q., Du, W., et al. (2017). Mineral types and organic matters of the Ordovician-Silurian Wufeng and Longmaxi shale in the Sichuan Basin, China: Implications for pore systems, diagenetic pathways, and reservoir quality in fine-grained sedimentary rocks. Marine and Petroleum Geology, 86, 55–674.

    Article  Google Scholar 

  • Zhou, S. D., Liu, D. M., Cai, Y. D., Karpyn, Z., & Yao, Y. B. (2018). Comparative analysis of nanopore structure and its effect on methane adsorption capacity of Southern Junggar coalfield coals by gas adsorption and FIB-SEM tomography. Microporous and Mesoporous Materials, 272, 117–128.

    Article  Google Scholar 

  • Zou, C. N., Dong, D. Z., Wang, S. J., Li, J. Z., Li, X. J., Wang, Y. M., et al. (2000). Geological characteristics and resource potential of shale gas in China. Petroleum Exploration and Development, 37, 641–653.

    Article  Google Scholar 

  • Zou, C. N., Yang, Z., Dai, J. X., Dong, D. Z., Zhang, B. M., Wang, Y. M., et al. (2015). The characteristics and significance of conventional and unconventional Sinian-Silurian gas systems in the Sichuan Basin, Central China. Marine and Petroleum Geology, 64, 386–402.

    Article  Google Scholar 

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Acknowledgments

This study was funded by the National Construction of High-Quality University Projects of Graduates from China Scholarship Council [Grant Number 201906440098]. We acknowledge Editor-in-Chief John Carranza Ph.D. and three anonymous reviewers for their valuable comments and suggestions.

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Authors and Affiliations

  1. School of Earth Science and Resources, Chang’an University, Xi’an, 710054, China

    Yang Wang & Hongfei Cheng

  2. State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum (Beijing), Beijing, 102249, China

    Yang Wang & Luofu Liu

  3. College of Geosciences, China University of Petroleum (Beijing), Beijing, 102249, China

    Yang Wang & Luofu Liu

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Wang, Y., Liu, L. & Cheng, H. Gas Adsorption Characterization of Pore Structure of Organic-rich Shale: Insights into Contribution of Organic Matter to Shale Pore Network. Nat Resour Res 30, 2377–2395 (2021). https://doi.org/10.1007/s11053-021-09817-5

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