党河流域敦煌盆地地下水补给与演化研究

摘要/Abstract

摘要： 综合应用水文地球化学指标和稳定同位素技术研究了党河流域敦煌盆地地下水补给和演化规律。岩盐、石膏及芒硝等矿物的溶解对Na⁺、Ca²⁺、Cl^-及SO₄^2-离子浓度影响较大。阳离子交换作用明显,地下水中Mg²⁺和Ca²⁺浓度增加,并与碳酸盐发生沉淀,导致HCO₃^-减少。地下水的δ¹⁸O值介于-12.1‰~-7.5‰,δ²H值变化范围为-84.3‰~-61.5‰,指示了盆地不同地带地下水补给来源不同。潜水δ¹⁸O和δ²H数值随着地下水径流路径方自西南到东北越来越富集,反映了蒸发浓缩效应,南湖、盆地南部潜水同位素与河水相近,体现了现代补给。相比之下,承压水稳定同位素相对贫乏,指示过去寒冷时期的补给。该研究可以为敦煌区域地下水资源规划和管理提供一定的借鉴意义。

关键词: 地下水, 水文地球化学, 稳定同位素, 敦煌盆地

Abstract: The groundwater supply in arid areas played a pivotal role in many fields. Firstly,it is closely related with some environmental problems such as desertification,storms and salinization. Secondly,it is a very important factor to control the economic development especially for the irrigation agriculture. The Dunhuang Basin,located in the Danghe River Basin,is facing serious groundwater problems. Additionally,tourism industry in this region is very developed but the ecological environment is rather fragile,therefore,to get an insight into the characteristics of groundwater in this region is the precondition for solving the groundwater problems. The groundwater water chemical type is a concentrated reflection of the groundwater chemical composition,and a system response of the whole water and groundwater circulation characteristics. Studies of the variation characteristics and the evolution of groundwater can better reveal the interaction mechanism of groundwater and environment. By using hydro-chemical and stable isotopic technology,this paper determined the evolution way of ground water hydro-chemical characteristics,the recharge environment of groundwater in the study area,and the physical and chemical properties of groundwater. Results show that the quality of groundwater and surface water was generally good with low salinity and unpolluted. The relationships between Na⁺ and SO₄^2-,Cl^- and Na⁺,as well as Ca²⁺ and SO₄^2- were quite good,indicating that the dissolution of rock salt,glauber's salt and gypsum had great influences on the concertration of Ca²⁺,Na⁺,SO₄^2- and Cl^-. Reverse cation exchange played an important role in the concentration of Ca²⁺ and Mg²⁺,and with the increase of Ca²⁺ and Mg²⁺ in groundwater,carbonate started to precipitation, leading to a reduction of HCO₃^-. This reaction was accelerated by the preceding hydro-geochemical evolution, especially the dissolution of the glauber's salt. The increase of Na⁺ can cause the cation exchange between Na⁺ of the groundwater and Ca²⁺ or Mg²⁺ of the aquifer. For stable isotope,δ¹⁸O ranged from -10.8‰ to -7.7‰, and δ²H from -74.4‰ to -52.5‰,indicating that the recharge environment had changed significantly in the recharge history. δ¹⁸O and δ²H values in unconfined groundwater increased along the groundwater flow path from SW to NE,reflecting the effect of evaporation and concentration. The stable isotope values in Nanhu group and southern of Dunhuang Basin were close to the surface water,indicating that the surface water had an important recharge for phreatic water. In contrast,stable isotopes in confined groundwater was relatively poor,revealing that the deep confined groundwater may be supplied under a cold climate conditions in the past. The results not only have important implications for water resources allocation and groundwater management,but also can help the further study about the regional groundwater circulation characteristics in the Dunhuang Basin.

Key words: groundwater, hydrogeochemistry, stable isotope, Dunhuang Basin

中图分类号:

P641.2

赵玮, 马金珠, 何建华. 党河流域敦煌盆地地下水补给与演化研究[J]. 干旱区地理, 2015, 38(6): 1133-1141.

ZHAO Wei, MAJin-zhu, HE Jian-hua. Groundwater recharge and geochemical evolution in the Dunhuang Basin of Danghe River,northwest China[J]. , 2015, 38(6): 1133-1141.

参考文献

[1] VAIRAVAMOORTHY K, GORANTIWAR S D, PATHIRANA A. Managing urban water supplies in developing countries-climate change and water scarcity scenarios[J]. Physics and Chemistry of the Earth, 2008, 33:330-339.

[2] 陈亚宁,杨青,罗毅等.西北干旱区水资源问题研究思考[J].干旱区地理, 2012, 35(1):1-12.[CHEN Yaning, YANG Qing, LUO Yi, et al. Ponder on the issues of water resources in the arid region of northwest China[J]. Arid Land Geography, 2012, 35(1):1-12.]

[3] 闫成云.疏勒河流域中下游三大盆地地下水潜力评价[J].甘肃地质, 2006, (2):81-84.[YAN Chengyun. Evaluation of the groundwater potential of the three basins at the middle and lower reaches of the Shule River basin[J]. Gansu Geology, 2006, (2):81-84.]

[4] 周长进,董锁成,李岱,等.敦煌市水资源的可持续利用及调控对策[J].自然资源学报, 2007, (4):516-523.[ZHOU Changjin, DONG Suocheng, LI Dai, et al. The characteristics and the sustainable utilization of water resource in Dunhuang City of Gansu Province, China[J]. Journal of Natural Resources, 2007, (4):516-523.]

[5] 张明泉,赵转军,曾正中.敦煌盆地水环境特征与水资源可持续利用[J].干旱区资源与环境, 2003, (4):71-77.[ZHANG Ming-quan, ZHAO Zhuanjun, ZENG Zhengzhong. The characteristics of water system and the sustainable utilization of water resources in Dunhuang Basin[J]. Journal of Arid Land Resources and Environment, 2003, (4):71-77.]

[6] 王昭,陈德华.疏勒河流域水资源开发及其对生态环境的影响[J].地球学报, 2002, B(3):14-17.[WANG Zhao, CHEN Dehua. Exploitation of water resources and its impacts on eco-environment on the Shule River Basin[J]. Acta Geoscientica Sinica, 2002, B(3):14-17.]

[7] 林中凯,蔡利飘,罗婷婷,等.敦煌盆地地层发育特征分析[J].内江科技, 2012, (3):149.[LIN Zhongkai, CAI Lipiao, LUO Ting-ting, et al. The analysis of stratum characteristic in Dunhuang basin[J]. Neijiang Science, 2012, (3):149.]

[8] 桑学锋.敦煌盆地地下水数值模拟及可视化与管理[D].兰州:兰州大学, 2006.[SANG Xuefeng. Visual simulation and management of groundwater in Dunhuang basin[D]. Lanzhou:Lanzhou University, 2006.]

[9] 张清寰,齐识,马金珠.甘肃梨园河流域地下水来源及其水化学特征[J].干旱区研究, 2012, 29(5):898-906.[ZHANG Qinghuan, QI Shi, MA Jinzhu. The sources and hydrochemical properties of groundwater in the Liyuan River Basin, Gansu Province[J]. Arid Zone Research, 2012, 29(5):898-906.]

[10] EDMUNDS W M, GUENDOUZ A H, MAMOU A, et al. Groundwater evolution in the Continental Intercalaire aquifer of southern Algeria and Tunisia:trace element and isotopic indicators[J]. Applied Geochemistry, 2003, 18(6):805-822.

[11] MULLANEY J R, LORENZ D L, ARNTSON A D. Chloride in groundwater and surface water in areas underlain by the glacial aquifer system, northern United States[M]. Reston, VA:US Geological Survey, 2009:567.

[12] 陈植华,徐恒力.确定干旱-半干旱地区降水入渗补给量的新方法-氯离子示踪法[J].地质科技情报, 1996, 15(3):87-92.[CHEN Zhihua, XU Hengli. Chloride tracer method for estimation natural groundwater recharge in arid and semiarid regions[J]. Geological Science and Technology Information, 1996, 15(3):87-92.]

[13] DEMETRIADES A. General ground water geochemistry of Hellas using bottled water samples[J]. Journal of Geochemical Exploration, 2010, 107(3):283-298.

[14] 朱海勇,陈永金,刘加珍,等.塔里木河中下游地下水化学及其演变特征分析[J].干旱区地理, 2013, 36(1):8-18.[ZHU Haiyong, CHEN Yongjin, LIU Jiazhen, et al. Variation and evolution of groundwater chemistry in the middle and lower reaches of the Tarim River[J]. Arid Land Geography, 2013, 36(1):8-18.]

[15] SCHOELLER H. Hydrodynamique dans le karst[J]. Chronique d'Hydrogéologie, 1967, 10:7-21.

[16] 张鸿义,曾凡江,安海棠.中国干旱区浅层地下水的形成、分布与运移[J].干旱区研究, 2011, 28(1):67-73.[ZHANG Hongyi, ZENG Fanjiang, AN Haitang. Formation, distribution and transport of shallow groundwater in Arid Areas, China[J]. Arid Zone Research, 2011, 28(1):67-73.]

[17] 马金辉,韩金华,张艳林.近10 a来民勤盆地地下水埋深的空间异质性分析[J].干旱区地理, 2013, 36(1):1-7.[MA Jinhui, HAN Jinhua, ZHANG Yanlin. Spatial heterogeneity of Minqin Basin's groundwater depth in recent 10 years[J]. Arid Land Geography, 2013, 36(1):1-7.]

[18] MA Jinzhu, HE Jianhua, QI Shi, et al. Groundwater recharge and evolution in the Dunhuang Basin, northwestern China[J]. Applied Geochemistry, 2013, 28:19-31.

[19] MA Jinzhu, PAN Feng, CHEN Lihua, et al. Isotopic and geochemical evidence of recharge sources and water quality in the Quaternary aquifer beneath Jinchang City, NW China[J]. Applied Geochemistry. 2010, 25(7):996-1007.

[20] EDMUNDSWM, MAJinzhu, AESCHBACH-HERTIGW, et al. Groundwater recharge history and hydrogeochemical evolution in the Minqin Basin, North West China[J]. Applied Geochemistry, 2006, 21:2148-2170.

[21] ZHU Gaofeng, SU Yonghong, FENG Qi. The hydrochemical characteristics and evolution of groundwater and surface water in the Heihe River Basin, northwest China[J]. Hydrogeology Journal, 2008, 16:167-182.

[22] MA Jinzhu, WANG Xiongshi, EDMUNDS W M. The characteristics of ground-water resources and their changes under the impacts of human activity in the arid northwest China:a case study of the Shiyang River Basin[J]. Journal of Arid Environments. 2005, 61:277-295.