Experimental study of the permeability evolution of fractured mudstone under complex stress paths
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摘要: 油氣主要儲集在巖石孔隙和縫洞內，深部復雜應力環境下儲層巖石裂隙滲透演化直接影響油氣的運移規律，是油氣勘探開發的重要研究對象。為了解復雜應力路徑下含裂隙巖石的滲透演化特性，利用高精度滲流?應力耦合三軸實驗設備，對含隨機分布裂隙泥巖開展了單試樣?復雜應力路徑加卸載過程中的滲透性演化試驗研究，試驗方案依次為：(i) 圍壓遞增條件下滲透性測試；(ii) 滲透壓力遞增條件下滲透性測試；(iii) 偏應力循環加卸載條件下滲透性測試；(iv) 圍壓、偏應力同步增長條件下滲透性測試。結果表明裂隙泥巖中的滲流可視為低滲流速度的層流；裂隙發育豐富巖樣（R2）滲透率及應力敏感性明顯較高。滲透率隨滲透壓力、圍壓分別呈正、負的指數函數變化。偏應力加載導致滲透率降低，卸載引起滲透率上升，但整體呈不可逆降低；圍壓、偏應力同步增長引起滲透率呈下降趨勢，并逐步趨于穩定；圍壓10.3 MPa作用下，滲透率基本保持恒定。由此，基于裂隙雙重介質模型，考慮泥巖變形過程中裂隙系統和基質系統的相互作用以及外部應力作用下的裂隙膨脹變形，構建了裂隙泥巖滲透率演化力學模型；模型模擬結果與試驗結果具有較好的一致性。相關成果可為裂隙泥巖滲透性演化預測和油氣高效開采提供重要的理論依據。Abstract: The main reservoirs of oil and gas are in the pores and fractures of rocks. Under deep and complex stress environments, reservoir rock fracture permeability evolution directly affects the flow of oil and gas, which is an important research object of oil and gas exploration and development. In order to study the permeability evolution of fractured rock under complex stress paths, a permeability test of a single sample in the process of loading and unloading complex stress paths was performed using high-precision hydro-mechanics coupled with triaxial experimental equipment. The experimental scheme entails permeability tests under (i) increasing confining pressure; (ii) increasing liquid pressure; (iii) cyclic loading and unloading deviatoric stress; and (iv) increasing confining pressure and deviatoric stress synchronously. The results show that liquid flow in fractured mudstone can be regarded as laminar flow with low velocity. The sample containing more fracture (R2) has a significantly higher permeability and stress sensitivity. The permeability changes with both liquid and confining pressure as a function of positive and negative exponential functions. The increase in deviatoric stress leads to a decrease in permeability, and unloading causes permeability to increase. The whole evolution of permeability is irreversibly reduced. During the increasing confining pressure and deviatoric stress stage, permeability also decreases, and tends to stabilize. Under a confining pressure of 10.3 MPa, permeability remains basically constant. Therefore, based on the double medium model of fracture, the permeability evolution model of fractured rock was proposed considering the interaction among fracture system, matrix system, and the expansion deformation of fracture under external stress. The simulation results of the model are in good agreement with the experimental results. These results can provide an important theoretical basis for the prediction of permeability evolution of fractured mudstone and efficient oil and gas exploitation.
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圖 1 裂隙泥巖巖樣制備。（a）巖樣劈裂試驗；（b）裂隙泥巖巖樣；（c）微觀結構光學薄片鑒定, 顆粒粒徑：石英（0.02～015 mm），長石（0.02～0.1 mm），其他（0.02~0.5 mm）
Figure 1. Preparation of fractured mudstone sample: (a) mudstone sample splitting test; (b) fractured mudstone sample; (c) photomicrographs of thin sections of microstructure, particle size: quartz (0.02–015 mm), feldspar (0.02–0.1 mm), others (0.02–0.5 mm)
圖 3 滲流速度與滲透壓差的關系。（a）R1巖樣；（b）R2巖樣
Figure 3. Relationship between liquid velocity and liquid pressure difference: (a) R1 sample; (b) R2 sample
圖 4 圍壓遞增滲透性測試方案
Figure 4. Schematic of permeability test with increasing confining pressure
圖 5 圍壓遞增條件下滲透率演化（圖中R為擬合曲線的相關系數）。（a）R1巖樣；（b）R2巖樣
Figure 5. Permeability evolution with increasing confining pressure（R in the figure is the correlation coefficient of fitting curve）: (a) R1 sample; (b) R2 sample
圖 6 圍壓遞增條件下滲透率比變化
Figure 6. Change in permeability ratio with increasing confining pressure
圖 7 滲透壓力遞增滲透性測試方案
Figure 7. Schematic of permeability test with increasing liquid pressure
圖 8 滲透壓力遞增條件下滲透率演化。（a）R1巖樣；（b）R2巖樣
Figure 8. Permeability evolution with increasing liquid pressure: (a) R1 sample; (b) R2 sample
圖 9 滲透壓力遞增條件下滲透率比演化
Figure 9. Change in permeability ratio with increasing liquid pressure
圖 10 有效應力變化條件下滲透率演化。（a）R1巖樣；（b）R2巖樣
Figure 10. Permeability evolution with changing effective stress: (a) R1 sample; (b) R2 sample
圖 11 偏應力循環加卸載滲透性測試方案
Figure 11. Schematic of permeability test for cyclic loading and unloading of deviatoric stress
圖 12 偏應力循環加卸載和滲透率關系。（a）R1巖樣；（b）R2巖樣
Figure 12. Relationship between cyclic loading and unloading of deviatoric stress and permeability: (a) R1 sample; (b) R2 sample
圖 13 偏應力循環加卸載和滲透率比關系
Figure 13. Relationship between cyclic loading and unloading of deviatoric stress and permeability ratio
圖 14 偏應力0 MPa加卸載和滲透率比關系
Figure 14. Relationship between loading and unloading and permeability ratio under deviatoric stress, 0 MPa
圖 15 圍壓、偏壓增長下滲透性測試方案（滲透壓力：3.5 MPa）
Figure 15. Schematic of permeability test for increasing confining pressure and deviatoric stress（Liquid pressure：3.5 MPa）
圖 16 圍壓、偏壓增長和滲透率關系。（a）R1巖樣；（b）R2巖樣
Figure 16. Relationship between increasing confining pressure and deviatoric stress and permeability: (a) R1 sample; (b) R2 sample
圖 17 不同偏壓下滲透演化規律。（a）R1巖樣；（b）R2巖樣
Figure 17. Permeability evolution under variable deviatoric stress: (a) R1 sample; (b) R2 sample
圖 18 圍壓、偏壓增長和滲透率比關系
Figure 18. Relationship between increasing confining pressure and deviatoric stress and permeability ratio
圖 20 R1巖樣滲透性演化模擬結果。（a）圍壓遞增；（b）滲透壓力遞增；（c）偏應力循環加載；（d）圍壓、偏應力同步加載
Figure 20. Simulation results of permeability evolution of R1 sample: (a) increasing confining pressure; (b) increasing liquid pressure; (c) cyclic loading and unloading deviatoric stress; (d) increasing confining pressure and deviatoric stress synchronously
圖 21 R2巖樣滲透性演化模擬結果。（a）圍壓遞增；（b）滲透壓力遞增；（c）偏應力循環加載；（d）圍壓、偏應力同步加載
Figure 21. Simulation results of permeability evolution of R2 sample: (a) increasing confining pressure; (b) increasing liquid pressure; (c) cyclic loading and unloading deviatoric stress; (d) increasing confining pressure and deviatoric stress synchronously
表 1 滲透率演化力學模型參數。（a）R1巖樣；（b）R2巖樣
Table 1. Parameters of permeability evolution mechanical model: (a) R1 sample; (b) R2 sample
(a) Stress loading Parameter $s /b $ ${K_{{\rm{f0}}}}{\rm{/}}{{\rm{m}}^2}$ ${K_{\rm{m}}}{\rm{/}}{{\rm{m}}^2}$ $D/{\rm{MP}}{{\rm{a}}^{ - 1}}$ Dm/MPa?1 $\,\beta $ Increasing confining pressure 0.02 3.30×10?19 0.99×10?19 0.313 0.697 Increasing liquid pressure 0.27 3.64×10?19 0.240 0.337 Cyclic loading of deviatoric stress First cycle loading 0.52 3.02×10?18 0.168 0.348 3.05×10?9 Second cycle loading 1.89 2.32×10?18 0.477 0.658 3.22×10?9 Third cycle loading 0.73 2.44×10?18 0.301 0.521 3.76×10?9 Simultaneous loading of confining pressure and deviatoric stress Confining pressure: 7.3 MPa 0.84 1.47×10?18 0.278 0.484 3.56×10?9 Confining pressure: 8.3 MPa 0.58 7.58×10?19 0.314 0.630 3.39×10?9 Confining pressure: 9.3 MPa 0.64 0.55×10?19 0.098 0.436 3.66×10?9 Confining pressure: 10.3 MPa 0.17 0.77×10?19 0.062 0.126 3.12×10?9 (b) Stress loading Parameter $s/b$ ${K_{{\rm{f0}}}}{\rm{/}}{{\rm{m}}^2}$ ${K_{\rm{m}}}{\rm{/}}{{\rm{m}}^2}$ $D/{\rm{MP}}{{\rm{a}}^{ - 1}}$ ${D_{\rm{m}}}/{\rm{MP}}{{\rm{a}}^{ - 1}}$ $\beta $ Increasing confining pressure 0.81 2.35×10?17 1.00×10?18 0.528 0.729 Increasing liquid pressure 0.74 2.28×10?17 0.395 0.563 Cyclic loading of deviatoric stress First cycle loading 0.54 1.85×10?16 0.157 0.323 3.10×10?9 Second cycle loading 0.03 1.38×10?16 0.097 0.376 3.89×10?9 Third cycle loading 0.80 7.04×10?17 0.459 0.756 3.31×10?9 Simultaneous loading of confining pressure and deviatoric stress Confining pressure: 7.3 MPa 0.26 4.97×10?17 0.043 0.124 3.78×10?9 Confining pressure: 8.3 MPa 0.05 3.01×10?17 0.088 0.337 3.98×10?9 Confining pressure: 9.3 MPa 0.80 1.15×10?17 0.203 0.365 3.01×10?9 Confining pressure: 10.3 MPa 0.66 3.20×10?18 0.095 0.200 3.06×10?9 
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參考文獻
[1] Zou C N, Zhao W Z, Jia C Z, et al. Formation and distribution of volcanic hydrocarbon reservoirs in sedimentary basins of China. Petrol Explor Dev, 2008, 35(3): 257 doi: 10.3321/j.issn:1000-0747.2008.03.001鄒才能, 趙文智, 賈承造, 等. 中國沉積盆地火山巖油氣藏形成與分布. 石油勘探與開發, 2008, 35(3):257 doi: 10.3321/j.issn:1000-0747.2008.03.001 [2] He Y D, Wei C G. The present situation and research direction of evaluation methods in fracture type reservoir. Prog Geophys, 2007, 22(2): 537 doi: 10.3969/j.issn.1004-2903.2007.02.028何雨丹, 魏春光. 裂縫型油氣藏勘探評價面臨的挑戰及發展方向. 地球物理學進展, 2007, 22(2):537 doi: 10.3969/j.issn.1004-2903.2007.02.028 [3] Zhou H G, Guo J C, Li J, et al. A study on the influence rule of the fracture characteristics on rock seepage characteristics. J Geomech, 2017, 23(4): 531 doi: 10.3969/j.issn.1006-6616.2017.04.004周漢國, 郭建春, 李靜, 等. 裂隙特征對巖石滲流特性的影響規律研究. 地質力學學報, 2017, 23(4):531 doi: 10.3969/j.issn.1006-6616.2017.04.004 [4] Fujii T, Funatsu T, Oikawa Y, et al. Evolution of permeability during fracturing processes in rocks under conditions of geological storage of CO2. Mater Trans, 2015, 56(5): 679 doi: 10.2320/matertrans.M-M2015802 [5] Wang S, Yu Q L, Wang L. Effect of fracture roughness on permeability coefficient under uniaxial compression. Chin J Eng, https://doi.org/10.13374/j.issn2095-9389.2020.05.26.001王帥, 于慶磊, 王玲. 單軸壓縮條件下裂隙粗糙度對滲透系數的影響. 工程科學學報. https://doi.org/10.13374/j.issn2095-9389.2020.05.26.001 [6] Wang H Y. Hydraulic fracture propagation in naturally fractured reservoirs: Complex fracture or fracture networks. J Nat Gas Sci Eng, 2019, 68: 102911 doi: 10.1016/j.jngse.2019.102911 [7] Li S, Luo M K, Fan C J, et al. Quantitative characterization of the effect of acidification in coals by NMR and low-temperature nitrogen adsorption. J China Coal Soc, 2017, 42(7): 1748李勝, 羅明坤, 范超軍, 等. 基于核磁共振和低溫氮吸附的煤層酸化增透效果定量表征. 煤炭學報, 2017, 42(7):1748 [8] Yao J, Huang Z Q, Liu W Z, et al. Key mechanical problems in the development of deep oil and gas reservoirs. Sci Sin Phys Mech Astron, 2018, 48(4): 044701 doi: 10.1360/SSPMA2017-00272姚軍, 黃朝琴, 劉文政, 等. 深層油氣藏開發中的關鍵力學問題. 中國科學(物理學 力學 天文學), 2018, 48(4):044701 doi: 10.1360/SSPMA2017-00272 [9] Zhang Y, Xu W Y, Zhao H B, et al. Experimental investigation on permeability evolution of sandstone from fractured zone under coupling action of hydro? mechanical?creep. J China Univ Petrol, 2014, 38(4): 154張玉, 徐衛亞, 趙海斌, 等. 滲流?應力?流變耦合作用下破碎帶砂巖滲透演化規律試驗研究. 中國石油大學學報: 自然科學版, 2014, 38(4):154 [10] Zhang Y, Liu Z B, Xu W Y, et al. Change in the permeability of clastic rock during multi-loading triaxial compressive creep tests. Géotech Lett, 2015, 5(3): 167 [11] Jia C J, Xu W Y, Wang H L, et al. Laboratory investigations of inert gas flow behaviors in compact sandstone. Environ Earth Sci, 2018, 77(6): 245 doi: 10.1007/s12665-018-7423-5 [12] Yu J, Li H, Chen X, et al. Triaxial experimental study of associated permeability-deformation of sandstone under hydro-mechanical coupling. Chin J Rock Mech Eng, 2013, 32(6): 1203 doi: 10.3969/j.issn.1000-6915.2013.06.014俞縉, 李宏, 陳旭, 等. 滲透壓?應力耦合作用下砂巖滲透率與變形關聯性三軸試驗研究. 巖石力學與工程學報, 2013, 32(6):1203 doi: 10.3969/j.issn.1000-6915.2013.06.014 [13] Zhang Y, Shao J F, Xu W Y, et al. Creep behaviour and permeability evolution of cataclastic sandstone in triaxial rheological tests. Eur J Environ Civil Eng, 2015, 19(4): 496 doi: 10.1080/19648189.2014.960103 [14] Min K B, Rutqvist J, Tsang C F, et al. Stress-dependent permeability of fractured rock masses: a numerical study. Int J Rock Mech Min Sci, 2004, 41(7): 1191 doi: 10.1016/j.ijrmms.2004.05.005 [15] Liu W Q, Li Y S, Wang B. Gas permeability of fractured sandstone/coal samples under variable confining pressure. Transp Porous Media, 2010, 83(2): 333 doi: 10.1007/s11242-009-9444-8 [16] Yang J B, Feng X T, Pan P Z. Experimental study of permeability characteristics of single rock fracture considering stress history. Rock Soil Mech, 2013, 34(6): 1629楊金保, 馮夏庭, 潘鵬志. 考慮應力歷史的巖石單裂隙滲流特性試驗研究. 巖土力學, 2013, 34(6):1629 [17] Man K, Liu X L, Su R, et al. Permeability measuring of large scaled single fractured media with a seepage stress coupling testing apparatus. Chin J Rock Mech Eng, 2015, 34(10): 2064滿軻, 劉曉麗, 蘇銳, 等. 大尺度單裂隙介質應力?滲流耦合試驗臺架及其滲透系數測試研究. 巖石力學與工程學報, 2015, 34(10):2064 [18] Yu H D, Chen F F, Chen W Z, et al. Research on permeability of fractured rock. Chin J Rock Mech Eng, 2012, 31(Suppl 1): 2788于洪丹, 陳飛飛, 陳衛忠, 等. 含裂隙巖石滲流力學特性研究. 巖石力學與工程學報, 2012, 31(增刊1): 2788 [19] Zhao Y L, Fu C C, Wang Y X, et al. Tests on hydro-mechanical coupling characteristics of fractured limestone in complete stress−strain process. Chin J Rock Mech Eng, 2016, 35(Suppl 2): 3763趙延林, 付成成, 汪亦顯, 等. 全應力−應變過程中裂隙灰巖的水−力耦合特性試驗研究. 巖石力學與工程學報, 2016, 35(增刊2): 3763 [20] Nooraiepour M, Haile B G, Hellevang H. Compaction and mechanical strength of Middle Miocene mudstones in the Norwegian North Sea-The major seal for the Skade CO2 storage reservoir. Int J Greenhouse Gas Control, 2017, 67: 49 doi: 10.1016/j.ijggc.2017.10.016 [21] Corkum A G, Martin C D. The mechanical behaviour of weak mudstone (Opalinus Clay) at low stresses. Int J Rock Mech Min Sci, 2007, 44(2): 196 doi: 10.1016/j.ijrmms.2006.06.004 [22] Mao X B, Zhang L Y, Liu R X. Creep properties and damage constitutive relation of mudstone under uniaxial compression at high temperature. Chin J Geotech Eng, 2013, 35(Suppl 2): 30茅獻彪, 張連英, 劉瑞雪. 高溫狀態下泥巖單軸蠕變特性及損傷本構關系研究. 巖土工程學報, 2013, 35(增刊2): 30 [23] Monfared M, Sulem J, Delage P, et al. A laboratory investigation on thermal properties of the Opalinus claystone. Rock Mech Rock Eng, 2011, 44(6): 735 doi: 10.1007/s00603-011-0171-4 [24] Zhang H X, Liu W Q, Zhu L. Fracture permeability model and experiments of shale gas reservoirs. Rock Soil Mech, 2015, 36(3): 719張宏學, 劉衛群, 朱立. 頁巖儲層裂隙滲透率模型和試驗研究. 巖土力學, 2015, 36(3):719 -
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