GEOCHEMICAL MODELING OF SULFATE POLLUTION IN KARST WATER OF NIANGZIGUAN REGION, SHANXI PROVINCE, CHINA
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摘要: 通过分析娘子关泉域岩溶水的水文地球化学特征, 发现沿流动路径上硫酸根质量浓度逐渐降低, 矿化度逐渐降低, Ca2+, Mg2+与SO42-比值逐渐升高等特征.运用水岩作用的地球化学模拟软件模拟得出, 广泛出露分布的中陶统灰岩因含石膏而使地下水在补给—径流区和地下浅部即含有高硫酸根, 沿流动路径上在汇流区—排泄区地下水不断有侧向补给及与深部水的混合, 而表现出硫酸根质量浓度逐渐降低; 同时个别特高硫酸根的井水为石炭—二叠系中水污染中奥陶统含水层造成的.相对而言, 深部下奥陶统含水层的水质较好.Abstract: The hydro geochemical research into the karst water of Niangziguan spring area indicates the gradual decrease both in the concentration of sulfate and in the mineralization degree, but the gradual increase in the ratios between Ca2+, Mg2+ and SO42- along the flow path. The hydro geochemical modeling shows that the widely dissolving of gypsum causes the high concentration of gypsum from recharge area to discharge area, and even at the shallow aquifer. In addition, the mixing with deep water and sidewise water from the runoff to the discharge area reduces the concentration of sulfate in the water. The extraordinarily high concentration of sulfate was initiated by the pollution by the seepage from the Carboniferous-Permian where the oxidation of sulfide produced much higher sulfate in the Middle Ordovician aquifer. The water from the Lower Ordovician aquifer would be much better.
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Key words:
- karst water /
- pollution /
- sulfate /
- hydro geochemistry /
- modeling
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表 1 娘子关泉域天然水水化学特征平均统计
Table 1. Statistics for chemical components in groundwater in Niangziguan spring area
表 2 娘子关泉地下水主离子组分比值
Table 2. Ratios between main components in groundwater in Niangziguan spring area
表 3 矿物饱和溶解模型
Table 3. Dissolving model on saturation of mineral
表 4 模拟参数及结果
Table 4. Modeling parameters and results
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[1] 李义连. 山西娘子关岩溶水系统地球化学演化及模拟[D]. 武汉: 中国地质大学, 2000. [2] Parkhurst D L. Geochemical mole-balance modeling with uncertain data[J]. Water Resources Research, 1997, 33 (8): 1957~1970. doi: 10.1029/97WR01125 [3] Plummer L N, Busby J F, Lee R W, et al. Geochemical modeling of the madison aquifer in parts of Montana, Wyoming, and South Dokota[J]. Water Resource Research, 1990, 26(9): 1981~2014. doi: 10.1029/WR026i009p01981 [4] Plummer L N, Wigley T M L, Parkhurst D L. The kinetics of calcite dissolution in CO2-water system at 5-60 ℃ and 0.0-1.0 atm CO2[J]. Am J Sci, 1978, 278: 179~ 216. doi: 10.2475/ajs.278.2.179 [5] Plummer L N, Busenberg E. The solubilities of calcite, aragonite, and vaterite in CO2-H2O solutions between 0 and 90℃, and an evaluation of the aqueous model for the system CaCO3-CO2-H2O[J]. Geochim Cosmochim Acta, 1982, 46: 1011~1040. doi: 10.1016/0016-7037(82)90056-4 [6] Busenberg E, Plummer L N. Kinetic and thermodynamic factors controlling the distribution of SO42- and Na+ in calcites and selected aragonites[J]. Geochim Cosmochim Acta, 1985, 49: 713~725. doi: 10.1016/0016-7037(85)90166-8 [7] Harvie C E, Weare J H. The predication of mineral solubilities in natural water— the Na-K-Mg-Ca-Cl-SO4-H2O system from zero to higher concentrations at 25 ℃[J]. Geochim Cosmochim Acta, 1980, 44: 981~997. doi: 10.1016/0016-7037(80)90287-2 [8] Plummer L N, Back W. The mass balance approach: applications to interpreting the chemical evolution of hydrologic system[J]. Am J Sci, 1980, 280: 130~142. doi: 10.2475/ajs.280.2.130 [9] Plummer L N, Parkhurst D L, Thorstenson D C. Development of reaction models for ground water systems[J]. Geochim Cosmochim Acta, 1983, 47: 665~685. doi: 10.1016/0016-7037(83)90102-3