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Natural Fractures and Their Effectiveness in Deep Continental Shale Reservoirs of Permian Fengcheng Formation in Mahu Sag
Liu Guoping, Jin Zhijun, Zeng Lianbo, He Wenjun, Yang Sen, Li Shufeng, Du Xiaoyu, Lu Guoqing
PDF(10407 KB)
PDF(10407 KB)
Natural Fractures and Their Effectiveness in Deep Continental Shale Reservoirs of Permian Fengcheng Formation in Mahu Sag
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The continental shale in the Permian Fengcheng Formation of the Mahu Sag in the Junggar Basin has a maximum burial depth exceeding 5 000 m, rich in oil and gas resources. The widely developed natural fracture plays a crucial role in the accumulation and exploration of hydrocarbons in these reservoirs. A classification scheme is established for natural fractures in deep continental shale based on their geological genesis and occurrence by observing cores, image logs, thin sections, and SEM samples. Moreover, the development characteristics and effectiveness of different types of natural fractures Were analyzed, and the natural fracture heterogeneity and their contributions to reservoirs are discussed. Accordingly, natural fractures in deep continental shale are divided into tectonic, diagenetic, and abnormal high-pressure related fractures based on their geological genesis. Tectonic fractures can be subdivided into translayer shear, bed-parallel shear, and intralayer open fractures based on their occurrence, while diagenetic fractures are divided into bedding, stylolite, and shrinkage fractures. Tectonic fractures have relatively large scales, obvious groups, and high dipping and nearly vertical angles. Diagenetic fractures mainly develop horizontally, with curved surfaces and easily branched extensions. Intralayer open, bedding, and stylolite fractures are the dominant types of fractures in deep continental shale reservoirs. Natural fractures can be filled in varying degrees by minerals such as calcite and fine-grained mixtures containing organic matter, among which tectonic and bedding fractures are less filled, and stylolites are easier to be filled. Microscopic tectonic fractures have smaller apertures, while diagenetic fractures usually have larger apertures. This study speculates that tectonic fractures mainly provide effective pathways for fluid flow in reservoirs, while bedding fractures are more developed, which are not only seepage channels for reservoir fluid but also an important part of the effective storage space. The research results provide an important reference for improving the classification scheme of natural fractures in deep continental shale and for better understanding of the natural fracture distribution in such reservoirs.
natural fracture / fracture type / fracture effectiveness / deep continental shale / Fengcheng Formation in Mahu Sag / petroleum geology
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Aghli, G., Moussavi-Harami, R., Mohammadian, R., 2020. Reservoir Heterogeneity and Fracture Parameter Determination Using Electrical Image Logs and Petrophysical Data (a Case Study, Carbonate Asmari Formation, Zagros Basin, SW Iran). Petroleum Science, 17(1): 51-69. https://doi.org/10.1007/s12182-019-00413-0
|
|
Baud, P., Rolland, A., Heap, M., et al., 2016. Impact of Stylolites on the Mechanical Strength of Limestone. Tectonophysics, 690: 4-20. https://doi.org/10.1016/j.tecto.2016.03.004
|
|
Cao, Z., Liu, G. D., Kong, Y. H., et al., 2016. Lacustrine Tight Oil Accumulation Characteristics: Permian Lucaogou Formation in Jimusaer Sag, Junggar Basin. International Journal of Coal Geology, 153: 37-51. https://doi.org/10.1016/j.coal.2015.11.004
|
|
Ding, W.L., Xu, C.C., Jiu, K., et al., 2011. The Research Progress of Shale Fractures. Advances in Earth Science, 26(2): 135-144 (in Chinese with English abstract).
|
|
Gale, J. F. W., Lander, R. H., Reed, R. M., et al., 2010. Modeling Fracture Porosity Evolution in Dolostone. Journal of Structural Geology, 32(9): 1201-1211. https://doi.org/10.1016/j.jsg.2009.04.018
|
|
Gale, J. F. W., Laubach, S. E., Olson, J. E., et al., 2014. Natural Fractures in Shale: A Review and New Observations. AAPG Bulletin, 98(11): 2165-2216. https://doi.org/10.1306/08121413151
|
|
Gong, L., Zeng, L.B., Du, Y.J., et al., 2015. Influences of Structural Diagenesis on Fracture Effectiveness: A Case Study of the Cretaceous Tight Sandstone Reservoirs of Kuqa Foreland Basin. Journal of China University of Mining & Technology, 44(3): 514-519 (in Chinese with English abstract).
|
|
He, W.J., Qian, Y.X., Zhao, Y., et al., 2021. Exploration Implications of Total Petroleum System in Fengcheng Formation, Mahu Sag, Junggar Basin. Xinjiang Petroleum Geology, 42(6): 641-655 (in Chinese with English abstract).
|
|
Huang, Y.Y., Wang, G.W., Song, L.T., et al., 2022. Fracture Logging Identification and Effectiveness Analysis of Shale Reservoir of the Permian Fengcheng Formation in Mahu Sag, Junggar Basin. Journal of Palaeogeography (Chinese Edition), 24(3): 540-555 (in Chinese with English abstract).
|
|
Jin, J., Yang, Z.,Yilihamu, E., et al., 2018. Nanopore Characteristics and Oil-Bearing Properties of Tight Oil Reservoirs in Jimsar Sag, Junggar Basin. Earth Science, 43(5): 1594-1601 (in Chinese with English abstract).
|
|
Jin, Z.J., Bai, Z.R., Gao, B., et al., 2019. Has China Ushered in the Shale Oil and Gas Revolution? Oil & Gas Geology, 40(3): 451-458 (in Chinese with English abstract).
|
|
Jin, Z.J., Liang, X.P., Wang, X.J., et al., 2022. Shale Oil Enrichment Mechanism and Sweet Spot Selection of Fengcheng Formation in Mahu Sag, Junggar Basin. Xinjiang Petroleum Geology, 43(6): 631-639 (in Chinese with English abstract).
|
|
Jin, Z.J., Zhu, R.K., Liang, X.P., et al., 2021. Several Issues Worthy of Attention in Current Lacustrine Shale Oil Exploration and Development. Petroleum Exploration and Development, 48(6): 1276-1287 (in Chinese with English abstract).
|
|
Ju, W., You, Y., Feng, S.B., et al., 2020. Characteristics and Genesis of Bedding-Parallel Fractures in Tight Sandstone Reservoirs of Chang 7 Oil Layer, Ordos Basin. Oil & Gas Geology, 41(3): 596-605 (in Chinese with English abstract).
|
|
Kuang, L.C., Tang, Y., Lei, D.W., et al., 2012. Formation Conditions and Exploration Potential of Tight Oil in the Permian Saline Lacustrine Dolomitic Rock, Junggar Basin, NW China. Petroleum Exploration and Development, 39(6): 657-667 (in Chinese with English abstract).
|
|
Kuang, L.C., Zhi, D.M., Wang, X.J., et al., 2021. Oil and Gas Accumulation Assemblages in Deep to Ultra-Deep Formations and Exploration Targets of Petroliferous Basins in Xinjiang Region. China Petroleum Exploration, 26(4): 1-16 (in Chinese with English abstract).
|
|
Laubach, S. E., Reed, R. M., Olson, J. E., et al., 2004. Coevolution of Crack-Seal Texture and Fracture Porosity in Sedimentary Rocks: Cathodoluminescence Observations of Regional Fractures. Journal of Structural Geology, 26(5): 967-982. https://doi.org/10.1016/j.jsg.2003.08.019
|
|
Lei, H.Y., Guo, P., Meng, Y., et al., 2022. Pore Structure and Classification Evaluation of Shale Oil Reservoirs of Permian Fengcheng Formation in Mahu Sag. Lithologic Reservoirs, 34(3): 142-153 (in Chinese with English abstract).
|
|
Li, M.W., Jin, Z.J., Dong, M.Z., et al., 2020. Advances in the Basic Study of Lacustrine Shale Evolution and Shale Oil Accumulation. Petroleum Geology & Experiment, 42(4): 489-505 (in Chinese with English abstract).
|
|
Li, Y.L., Lu, S.L., Xia, D.L., et al., 2022. Development Characteristics and Main Controlling Factors of Natural Fractures in Shale Series of the Seventh Member of the Yanchang Formation, Southern Ordos Basin. Chinese Journal of Geology (Scientia Geologica Sinica), 57(1): 73-87 (in Chinese with English abstract).
|
|
Liu, G. P., Jin, Z. J., Zeng, L. B., et al., 2023. Natural Fractures in Deep Continental Shale Oil Reservoirs: A Case Study from the Permian Lucaogou Formation in the Eastern Junggar Basin, Northwest China. Journal of Structural Geology, 174(1): 104913. https://doi.org/10.1016/j.jsg.2023.104913
|
|
Liu, G. P., Zeng, L. B., Wang, X. J., et al., 2020. Natural Fractures in Deep Tight Gas Sandstone Reservoirs in the Thrust Belt of the Southern Junggar Basin, Northwestern China. Interpretation, 8(4): SP81-SP93. https://doi.org/10.1190/int-2020-0051.1
|
|
Liu, G. P., Zeng, L. B., Zhu, R. K., et al., 2021. Effective Fractures and Their Contribution to the Reservoirs in Deep Tight Sandstones in the Kuqa Depression, Tarim Basin, China. Marine and Petroleum Geology, 124: 104824. https://doi.org/10.1016/j.marpetgeo.2020.104824
|
|
Liu, J.S., Ding, W.L., Yang, H.M., et al., 2023. Natural Fractures and Rock Mechanical Stratigraphy Evaluation in Huaqing Area, Ordos Basin: A Quantitative Analysis Based on Numerical Simulation. Earth Science, 48(7): 2572-2588 (in Chinese with English abstract).
|
|
Tian, H., Zeng, L.B., Xu, X., et al., 2020. Characteristics of Natural Fractures in Marine Shale in Fuling Area, Sichuan Basin, and Their Influence on Shale Gas. Oil & Gas Geology, 41(3): 474-483 (in Chinese with English abstract).
|
|
Toussaint, R., Aharonov, E., Koehn, D., et al., 2018. Stylolites: A Review. Journal of Structural Geology, 114: 163-195. https://doi.org/10.1016/j.jsg.2018.05.003
|
|
Wang, J., Zhou, L., Liu, J., et al., 2022. Genetic Mechanism of the Huxiang Hydrothermal Dolomite: A Case Study of the Permian Fengcheng Formation in the Mahu Sag, Junggar Basin. Acta Sedimentologica Sinica, 42(1): 1-16 (in Chinese with English abstract).
|
|
Wang, X. J., Cui, B. W., Feng, Z. H., et al., 2023. In- Situ Hydrocarbon Formation and Accumulation Mechanisms of Micro- and Nano-Scale Pore-Fracture in Gulong Shale, Songliao Basin, NE China. Petroleum Exploration and Development, 50(6): 1269-1281. https://doi.org/10.1016/s1876-3804(24)60465-9
|
|
Wu, S.T., Zhu, R.K., Cui, J.G., et al., 2015. Characteristics of Lacustrine Shale Porosity Evolution, Triassic Chang 7 Member, Ordos Basin, NW China. Petroleum Exploration and Development, 42(2): 167-176 (in Chinese with English abstract).
|
|
Yang, Z., Zou, C.N., Wu, S.T., et al., 2019. Formation, Distribution and Resource Potential of the “Sweet Areas (Sections)” of Continental Shale Oil in China. Marine and Petroleum Geology, 102: 48-60. https://doi.org/10.1016/j.marpetgeo.2018.11.049
|
|
Zeng, L. B., Lyu, W. Y., Li, J., et al., 2016. Natural Fractures and Their Influence on Shale Gas Enrichment in Sichuan Basin, China. Journal of Natural Gas Science and Engineering, 30: 1-9. https://doi.org/10.1016/j.jngse.2015.11.048
|
|
Zeng, L. B., Gong, L., Zu, K.W., et al., 2012. Influence Factors on Fracture Validity of the Paleogene Reservoir, Western Qaidam Basin. Acta Geologica Sinica, 86(11): 1809-1814 (in Chinese with English abstract).
|
|
Zeng, L.B., Ma, S.J., Tian, H., et al., 2023. Research Progress of Natural Fractures in Organic Rich Shale. Earth Science, 48(7): 2427-2442 (in Chinese with English abstract).
|
|
Zeng, L. B., Tang, X. M., Wang, T. C., et al., 2012. The Influence of Fracture Cements in Tight Paleogene Saline Lacustrine Carbonate Reservoirs, Western Qaidam Basin, Northwest China. AAPG Bulletin, 96(11): 2003-2017. https://doi.org/10.1306/04181211090
|
|
Zhang, Y.Z., Zeng, L.B., Luo, Q., et al., 2018. Research on the Types and Genetic Mechanisms of Tight Reservoir in the Lucaogou Formation in Jimusar Sag, Junggar Basin. Natural Gas Geoscience, 29(2): 211-225 (in Chinese with English abstract).
|
|
Zhang, Y. Z., Zeng, L. B., Luo, Q., et al., 2020. Effects of Diagenesis on Natural Fractures in Tight Oil Reservoirs: A Case Study of the Permian Lucaogou Formation in Jimusar Sag, Junggar Basin, NW China. Geological Journal, 55(9): 6562-6579. https://doi.org/10.1002/gj.3822
|
|
Zhang, Z. C., Liu, K. Q., Wang, Z. L., et al., 2024. Detailed Characterization of Pore Results of Continental Shale Reservoir in Fengcheng Formation, Mahu Sag. ACS Omega, 9(21): 22923-22940. https://doi.org/10.1021/acsomega.4c02056
|
|
Zhao, W.Z., Hu, S.Y., Hou, L.H., et al., 2020. Types and Resource Potential of Continental Shale Oil in China and Its Boundary with Tight Oil. Petroleum Exploration and Development, 47(1): 1-10 (in Chinese with English abstract).
|
|
Zhi, D.M., Tang, Y., He, W.J., et al., 2021. Orderly Coexistence and Accumulation Models of Conventional and Unconventional Hydrocarbons in Lower Permian Fengcheng Formation, Mahu Sag, Junggar Basin. Petroleum Exploration and Development, 48(1): 38-51 (in Chinese with English abstract).
|
|
Zhi, D.M., Tang, Y., Zheng, M.L., et al., 2019. Geological Characteristics and Accumulation Controlling Factors of Shale Reservoirs in Fengcheng Formation, Mahu Sag, Junggar Basin. China Petroleum Exploration, 24(5): 615-623 (in Chinese with English abstract).
|
|
Zhou, T., Wang, H.B., Li, F.X., et al., 2020. Numerical Simulation of Hydraulic Fracture Propagation in Laminated Shale Reservoirs. Petroleum Exploration and Development, 47(5): 1039-1051 (in Chinese with English abstract).
|
|
Zolitschka, B., Francus, P., Ojala, A. E. K., et al., 2015. Varves in Lake Sediments: A Review. Quaternary Science Reviews, 117: 1-41. https://doi.org/10.1016/j.quascirev.2015.03.019
|
|
Zou, C.N., Yang, Z., Wang, H.Y., et al., 2019. “Exploring Petroleum Inside Source Kitchen”: Jurassic Unconventional Continental Giant Shale Oil & Gas Field in Sichuan Basin, China. Acta Geologica Sinica, 93(7): 1551-1562 (in Chinese with English abstract).
|
|
Zou, Y. S., Zhang, S. C., Zhou, T., et al., 2016. Experimental Investigation into Hydraulic Fracture Network Propagation in Gas Shales Using CT Scanning Technology. Rock Mechanics and Rock Engineering, 49(1): 33-45. https://doi.org/10.1007/s00603-015-0720-3
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