Preliminary modeling investigation on changes in Karst fractures and seepage field in rockmass between streams with equal water levels

JIAO Youjun; HUANG Qibo; WANG Xusheng; YU Qingchun

doi:10.16030/j.cnki.issn.1000-3665.202307009

2024 Vol. 51, No. 1

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JIAO Youjun, HUANG Qibo, WANG Xusheng, YU Qingchun. Preliminary modeling investigation on changes in Karst fractures and seepage field in rockmass between streams with equal water levels[J]. Hydrogeology & Engineering Geology, 2024, 51(1): 1-11. doi: 10.16030/j.cnki.issn.1000-3665.202307009

Citation:

JIAO Youjun, HUANG Qibo, WANG Xusheng, YU Qingchun. Preliminary modeling investigation on changes in Karst fractures and seepage field in rockmass between streams with equal water levels[J]. Hydrogeology & Engineering Geology, 2024, 51(1): 1-11. doi: 10.16030/j.cnki.issn.1000-3665.202307009

Preliminary modeling investigation on changes in Karst fractures and seepage field in rockmass between streams with equal water levels

1.
School of Water Resources and Environment, China University of Geosciences （Beijing）, Beijing　100083, China
2.
Institute of Karst Geology, CAGS/Karst Laboratory of Karst Dynamics, MNR & GZAR/International Research Center on Karst under the Auspices of UNESCO, Guilin , Guangxi　541004, China
3.
Pingguo Guangxi, Karst Ecosystem, National Observation and Research Station, Pingguo, Guangxi　531406, China
4.
Guangxi Karst Resources and Environment Research Center of Engineering Technology, Guilin, Guangxi　541004, China

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Corresponding author: WANG Xusheng, wxsh@cugb.edu.cn

Received Date: 16 July 2023

Revised Date: 14 August 2023

Publish Date: 15 January 2024

Abstract

Abstract

The analytical solution of distributed water table in an unconfined aquifer between streams has been obtained in classic groundwater hydraulics based on Dupuit’s assumption, and it is frequently used in engineering practice. However, the applicability of this analytical model to groundwater in karst fractures needs a further verification. A 2D profile model of discrete fractures in rockmass between streams with equal water levels was simulated, considering a rainfall infiltration rate of 100−800 mm/a. The random fracture network includes two fracture groups, steeply or slightly inclining with the same statistic average aperture of 0.01 cm. Phreatic surface were identified by checking the interface between saturated and unsaturated fractures. The equivalent hydraulic conductivity of saturated fractures was obtained from seepage simulations and compared to the inversely estimated result from the classical analytical solution. It indicates that the relative error of inverse estimation is smaller than 25%. Further, the change in fractures aperture due to dissolution of Karst rocks was simulated with predictions on the state of fractures and quasi-steady state seepage in a 10 ka period. It finds that the maximum of the fracture aperture reaches 0.07 cm, and the classical model can yield an equivalent hydraulic conductivity from water table distribution with the same order of magnitude as the real hydraulic conductivity. The simulation shows an irregular shape of water table and seepage springs on river sides, where the number of springs reduced gradually following the karstification process. Though the classical analytical model can be used to estimate the equivalent hydraulic conductivity of the fractured aquifer between streams, it is unable to reveal the irregular water table shape and predict the change in seepage in Karst fractures.
- divide area between streams /
- Karst fracture network /
- Dupuit’s assumption /
- equivalent permeability /
- dissolution

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References

[1]	陈崇希,林敏. 地下水动力学[M]. 武汉:中国地质大学出版社,1999. [CHEN Chongxi,LIN Min. Groundwater hydraulics[M]. Wuhan:China University of Geosciences Press,1999. (in Chinese) Google Scholar CHEN Chongxi, LIN Min. Groundwater hydraulics[M]. Wuhan: China University of Geosciences Press, 1999. （in Chinese） Google Scholar
[2]	王大纯,张人权,史毅虹,等. 水文地质学基础[M]. 北京:地质出版社,1995. [WANG Dachun,ZHANG Renquan,SHI Yihong,et al. Fundamentals of hydrogeology[M]. Beijing:Geological Publishing House,1995. (in Chinese) Google Scholar WANG Dachun, ZHANG Renquan, SHI Yihong, et al. Fundamentals of hydrogeology[M]. Beijing: Geological Publishing House, 1995. （in Chinese） Google Scholar
[3]	YU Qingchun,SHEN Jifang,WAN Junwei,et al. Some investigation on early organization of Karst system[J]. Journal of China University of Geosciences,1999,10:314 − 321. Google Scholar
[4]	HAN Pengfei,WANG Xusheng,WAN Li,et al. The exact groundwater divide on water table between two rivers:a fundamental model investigation[J]. Water,2019,11(4):685. doi: 10.3390/w11040685 CrossRef Google Scholar
[5]	LI Ruoyi,WANG Xusheng. Analytical investigation of the exact groundwater divide between rivers beyond the Dupuit–Forchheimer approximation[J]. Hydrological Processes,2021,35(2):e14036. doi: 10.1002/hyp.14036 CrossRef Google Scholar
[6]	张有天,王镭,陈平. 有地表入渗的岩体渗流分析[J]. 岩石力学与工程学报,1991,10(2):103 − 111. [ZHANG Youtian,WANG Lei,CHEN Ping. Analysis of water percolation in rockmass due to surface infiltration[J]. Chinese Journal of Rock Mechanics and Engineering,1991,10(2):103 − 111. (in Chinese with English abstract) Google Scholar ZHANG Youtian, WANG Lei, CHEN Ping. Analysis of water percolation in rockmass due to surface infiltration[J]. Chinese Journal of Rock Mechanics and Engineering, 1991, 10（2）: 103 − 111. （in Chinese with English abstract） Google Scholar
[7]	姚池,姜清辉,叶祖洋,等. 裂隙网络无压渗流分析的初流量法[J]. 岩土力学,2012,33(6):1896 − 1903. [YAO Chi,JIANG Qinghui,YE Zuyang,et al. Initial flow method for unconfined seepage problems of fracture networks[J]. Rock and Soil Mechanics,2012,33(6):1896 − 1903. (in Chinese with English abstract) doi: 10.3969/j.issn.1000-7598.2012.06.045 CrossRef Google Scholar YAO Chi, JIANG Qinghui, YE Zuyang, et al. Initial flow method for unconfined seepage problems of fracture networks[J]. Rock and Soil Mechanics, 2012, 33（6）: 1896 − 1903. （in Chinese with English abstract） doi: 10.3969/j.issn.1000-7598.2012.06.045 CrossRef Google Scholar
[8]	JIANG Qinghui,YAO Chi,YE Zuyang,et al. Seepage flow with free surface in fracture networks[J]. Water Resources Research,2013,49(1):176 − 186. doi: 10.1029/2012WR011991 CrossRef Google Scholar
[9]	KAUFMANN G,BRAUN J. Karst aquifer evolution in fractured rocks[J]. Water Resources Research,1999,35(11):3223 − 3238. doi: 10.1029/1999WR900169 CrossRef Google Scholar
[10]	徐维生,柴军瑞,陈兴周. 含自由面岩体裂隙网络非线性渗流分析的传导矩阵调整法[J]. 水动力学研究与进展A辑,2010,25(4):484 − 492. [XU Weisheng,CHAI Junrui,CHEN Xingzhou. The conductivity matrix reforming method about non-linear seepage with free surface in fracture network of rock mass[J]. Chinese Journal of Hydrodynamics,2010,25(4):484 − 492. (in Chinese with English abstract) doi: 10.3969/j.issn.1000-4874.2010.04.008 CrossRef Google Scholar XU Weisheng, CHAI Junrui, CHEN Xingzhou. The conductivity matrix reforming method about non-linear seepage with free surface in fracture network of rock mass[J]. Chinese Journal of Hydrodynamics, 2010, 25（4）: 484 − 492. （in Chinese with English abstract） doi: 10.3969/j.issn.1000-4874.2010.04.008 CrossRef Google Scholar
[11]	GABROVŠEK F,ROMANOV D,DREYBRODT W. Early karstification in a dual-fracture aquifer:The role of exchange flow between prominent fractures and a dense net of fissures[J]. Journal of Hydrology,2004,299(1/2):45 − 66. Google Scholar
[12]	薛亮,于青春. 岩溶水系统演化中河间地块分水岭消失过程的数值模拟分析[J]. 水文地质工程地质,2009,36(2):7 − 12. [XUE Liang,YU Qingchun. Numerical simulation for the disappearing of a watershed divide in a karst groundwater system[J]. Hydrogeology & Engineering Geology,2009,36(2):7 − 12. (in Chinese with English abstract) doi: 10.3969/j.issn.1000-3665.2009.02.003 CrossRef Google Scholar XUE Liang, YU Qingchun. Numerical simulation for the disappearing of a watershed divide in a karst groundwater system[J]. Hydrogeology & Engineering Geology, 2009, 36（2）: 7 − 12. （in Chinese with English abstract） doi: 10.3969/j.issn.1000-3665.2009.02.003 CrossRef Google Scholar
[13]	于青春,武雄,大西有三. 非连续裂隙网络管状渗流模型及其校正[J]. 岩石力学与工程学报,2006,25(7):1469 − 1474. [YU Qingchun,WU Xiong,OHNISHI Yuzo. Channel model for fluid flow in discrete fracture network and its modification[J]. Chinese Journal of Rock Mechanics and Engineering,2006,25(7):1469 − 1474. (in Chinese with English abstract) doi: 10.3321/j.issn:1000-6915.2006.07.026 CrossRef Google Scholar YU Qingchun, WU Xiong, OHNISHI Yuzo. Channel model for fluid flow in discrete fracture network and its modification[J]. Chinese Journal of Rock Mechanics and Engineering, 2006, 25（7）: 1469 − 1474. （in Chinese with English abstract） doi: 10.3321/j.issn:1000-6915.2006.07.026 CrossRef Google Scholar
[14]	王云,于青春,薛亮,等. 裂隙岩溶含水系统溢流泉演化过程的数值模拟[J]. 中国岩溶,2010,29(4):378 − 384. [WANG Yun,YU Qingchun,XUE Liang,et al. Numerical simulation for the evolution of the overflow spring in fracture-karst aquifer system[J]. Carsologica Sinica,2010,29(4):378 − 384. (in Chinese with English abstract) doi: 10.3969/j.issn.1001-4810.2010.04.005 CrossRef Google Scholar WANG Yun, YU Qingchun, XUE Liang, et al. Numerical simulation for the evolution of the overflow spring in fracture-karst aquifer system[J]. Carsologica Sinica, 2010, 29（4）: 378 − 384. （in Chinese with English abstract） doi: 10.3969/j.issn.1001-4810.2010.04.005 CrossRef Google Scholar
[15]	DREYBRODT W. The role of dissolution kinetics in the development of karst aquifers in limestone:A model simulation of karst evolution[J]. The Journal of Geology,1990,98(5):639 − 655. doi: 10.1086/629431 CrossRef Google Scholar
[16]	LIU Zaihua,DREYBROD W. Dissolution kinetics of calcium carbonate minerals in H₂O CO₂ solutions in turbulent flow:The role of the diffusion boundary layer and the slow reaction H₂O+ CO₂→ H⁺+ HCO₃⁻[J]. Geochimica et Cosmochimica Acta,1997,61(14):2879 − 2889. doi: 10.1016/S0016-7037(97)00143-9 CrossRef Google Scholar
[17]	张莉丽. 裂隙岩体渗透典型单元体存在性[D]. 北京:中国地质大学(北京),2011. [ZHANG Lili. Determining the representative elementary volumes of fracture rock mass based on permeability analysis[D]. Beijing:China University of Geosciences(Beijing),2011. (in Chinese with English abstract) Google Scholar ZHANG Lili. Determining the representative elementary volumes of fracture rock mass based on permeability analysis[D]. Beijing: China University of Geosciences（Beijing）, 2011. （in Chinese with English abstract） Google Scholar
[18]	GROVES C G,HOWARD A D. Minimum hydrochemical conditions allowing limestone cave development[J]. Water Resources Research,1994,30(3):607 − 615. doi: 10.1029/93WR02945 CrossRef Google Scholar
[19]	GROVES C G,HOWARD A D. Early development of karst systems:1. Preferential flow path enlargement under laminar flow[J]. Water Resources Research,1994,30(10):2837 − 2846. doi: 10.1029/94WR01303 CrossRef Google Scholar
[20]	万军伟,晁念英,沈继方,等. 湖北清江罗家坳河间地块岩溶系统碳循环特征[J]. 中国岩溶,1999,18(2):123 − 128. [WAN Junwei,CHAO Nianying,SHEN Jifang,et al. Study on the carbon cycle in a Karst system at the luojiaao interfluve along the Qingjiang River of westen Hubei,China[J]. Carsologica Sinica,1999,18(2):123 − 128. (in Chinese with English abstract) Google Scholar WAN Junwei, CHAO Nianying, SHEN Jifang, et al. Study on the carbon cycle in a Karst system at the luojiaao interfluve along the Qingjiang River of westen Hubei, China[J]. Carsologica Sinica, 1999, 18（2）: 123 − 128. （in Chinese with English abstract） Google Scholar
[21]	韩鹏飞,王旭升,蒋小伟,等. 氢氧同位素在地下水流系统的重分布:从高程效应到深度效应[J]. 水文地质工程地质,2023,50(2):1 − 12. [HAN Pengfei,WANG Xusheng,JIANG Xiaowei,et al. Redistribution of hydrogen and oxygen isotopes in groundwater flow systems:From altitude effect to depth effect[J]. Hydrogeology & Engineering Geology,2023,50(2):1 − 12. (in Chinese with English abstract) Google Scholar HAN Pengfei, WANG Xusheng, JIANG Xiaowei, et al. Redistribution of hydrogen and oxygen isotopes in groundwater flow systems: From altitude effect to depth effect[J]. Hydrogeology & Engineering Geology, 2023, 50（2）: 1 − 12. （in Chinese with English abstract） Google Scholar
[22]	陈崇希. Dupuit模型的改进——具入渗补给[J]. 水文地质工程地质,2020,47(5):1 − 4. [CHEN Chongxi. Improvement of Dupuit model:With infiltration recharge[J]. Hydrogeology & Engineering Geology,2020,47(5):1 − 4. (in Chinese with English abstract) Google Scholar CHEN Chongxi. Improvement of Dupuit model: With infiltration recharge[J]. Hydrogeology & Engineering Geology, 2020, 47（5）: 1 − 4. （in Chinese with English abstract） Google Scholar