【作者】 危润初；

【导师】 肖长来；

【作者基本信息】 吉林大学 ， 地下水科学与工程， 2014， 博士

【摘要】 本文依托于吉林省科技厅重点攻关项目“长白山天然矿泉水形成机理分析（编号：20100452）”，对靖宇国家级自然保护区的天然矿泉水形成机理展开专题研究。在收集研究区已有地质、水文地质、水文气象、泉水动态、遥感等资料的基础上，采用野外调查与室内实验、定性定量分析与计算机模拟相结合的方法，从矿泉水形成环境、地下水循环和水岩作用机制等3个方面对区内天然矿泉水的形成机理进行系统性的研究。（1）矿泉水形成环境联合GIS和RS技术对保护区地形地貌进行了分析。保护区玄武岩台地平均坡度为3.02°，地势平缓，主要的土地覆盖类型为林地、季节性沼泽，两者总面积为190.9km2，占研究区总面积的91.1%，其中沼泽面积为38.5km2，占研究区总面积的18.4%。选择了12个生态环境评价指标，利用投影寻踪方法对保护区生态环境进行评价。评价结果表明，研究区生态环境等级为1级。特殊的台地地形、茂盛的森林、大面积的沼泽，这些为矿泉水形成提供了很好的水源涵养和补给条件，良好的生态环境为矿泉水优良的水质提供了可靠的生态环境保障。对保护区内玄武岩进行了取样分析。研究区主要的矿物为橄榄石、斜长石和辉石，SiO2的平均含量为50.20%，特殊的岩石地球化学背景是矿泉水溶质组分形成的基础。同时，玄武岩具有多层性特征，层顶、层底的气孔带、火山渣层（熔渣）、成岩裂隙、构造裂隙等构成了复杂的储水和导水系统，在区内形成了独特的熔岩孔洞裂隙地下水系统。由科学试验井分层抽水实验得到的玄武岩气孔带渗透系数在0.23~0.50m/d间。受特殊的地球化学条件和水文地质条件的影响，区内泉（井）水化学类型为重碳酸钙镁型和重碳酸镁钙型，水化学较稳定。矿泉水特征组分偏硅酸的浓度表现出了空间变异特征，随着深度的增加，偏硅酸浓度增加趋势明显，同时中部各泉（神龙泉-莱雅泉一带，含白浆泉）的偏硅酸平均浓度要略高于东北部各泉。地下水水化学特征表明，研究区地下水径流以浅中层为主。（2）地下水循环先后在区内取地下水同位素样21个，分别进行了稳定同位素18O、D和放射性同位素3H测试。研究区内大部分样品的氢氧稳定同位素都落在了长白山区大气降水线下方，沿当地蒸发线分布，这说明矿泉水的来源是大气降水，但经过了不同程度的蒸发作用。从西南往东北蒸发作用逐渐增强，不同深度的地下水的18O、 D值有明显差异，这反映出不同的补给环境。区内大部分泉井补给的主要来源是玄武岩台地上空的大气降水。3H测年结果表明，抗联泉和北山泉同位素年龄最小，研究区中部各泉（含白浆泉）的3H同位素年龄均在40a以上，区内最高；研究区东北部各泉（不含雪龙泉）同位素年龄最大不超过35a。同位素年龄呈现出“新-老-新”U形空间分布规律，这反映出各泉域地下水系统的相对独立性。以区内及邻近的77个火山和野外调查过程中确定的4个构造点为基础，运用Fuzzy c-lines算法和L_MSCMO算法对玄武岩台地的基底断裂进行了推测重构，推测出10条基底断裂。多期喷发的玄武岩覆盖在古老的盆地上，在区内形成盆地型的蓄水构造，同时受新构造运动的影响，沿古老断裂，玄武岩构造裂隙发育，岩石破碎，形成良好的导水通道，区内泉的分布反映了断裂构造的影响，以泉群和线性条带形式出露。本文提出基于断裂和地表集水域的泉域划分方法，并运用该方法对巨龙-飞龙泉群和神龙-九龙泉群进行了泉域划分，得到了2个泉域的范围和面积。神龙-九龙泉群的泉域面积为26.9km2，巨龙-飞龙泉域面积为45.5km2。在不考虑泉域其它排泄项的条件下计算得到2个泉群的降水入渗系数分别为0.317和0.330。同位素研究和泉域划分的结果表明，区内地下水循环具有局部性和相对独立性。区内泉水动态为降水-径流型，泉水的即时流量与前期一定时间尺度的累积降水量有关。泉流量动态对降水存在滞后，滞后的时间与泉域的补给环境有关。（3）水岩作用机制本文设计了静态浸泡实验和动态淋滤实验来研究水与玄武岩、火山渣和土壤相互作用过程。水与土壤、玄武岩和火山渣的作用主要表现在硅酸盐与铝硅酸盐矿物的水解，偏硅酸浓度随时间不断增加，后期趋于稳定，偏硅酸浓度土壤浸泡液>火山渣浸泡液>玄武岩浸泡液。虽然土壤浸泡液初期的pH小于7，但总体上来说，土壤、玄武岩和火山渣浸泡液pH值都呈现上升趋势，在后期稳定。除Cl-外，其它离子浓度变化趋势基本满足初期快速增加，后期趋缓至稳定。玄武岩和火山渣浸泡液Cl-表现为一次性溶出的特点，土壤浸泡液中Cl-浓度因为受到-NH2基的吸附影响而表现为随pH值的增加而逐渐增加。火山渣浸泡液偏硅酸溶出量相对较高，但是电导率、K+浓度、Na+浓度和HCO-3浓度为三种浸泡液最低，这与火山锥的降水淋溶环境有关。区内的土层呈酸性至微酸性反应，pH在5.0~5.5间。它不仅是区内矿泉水特征组分的重要物质来源，同时为地下水提供了低pH值的环境，是区内地下水CO2的重要来源，这就促进地下水与玄武岩的相互作用。淋滤实验结果表明，在流动的水体中玄武岩和火山渣矿物的水解速度更快。运动的水体不仅加速了溶液中组分的对流和弥散，而且对水岩反应所产生的中间层有淋蚀作用。为了进一步了解玄武岩地下水水岩作用矿物溶解趋势和规律，本文分别运用PHREEQC和TOUGHREACT软件进行了玄武岩地下水的反向和正向水文地球化学模拟。模拟结果表明，研究区玄武岩地下水径流过程中水岩作用主要表现为钙长石、镁橄榄石和辉石的水解，其中以钙长石的水解最多，矿泉水特征组分偏硅酸正是由这些矿物的水解所产生。铝硅酸盐的沉淀以钙蒙脱石为主，钠蒙脱石、高岭石沉淀较少。阳离子交换主要表现为水中的Ca2+置换出玄武岩中的Na+。TOUGHREACT模拟结果同时表明，断裂改变了地下水流场的形态，加速了地下水循环，客观上形成汇水和导水通道，从而影响地下水系统的水岩作用过程，对玄武岩地下水的水岩作用及各溶解组分的浓度和空间分布有重要的影响。更多还原

【Abstract】 The thesis is supported by the key scientific and technological project of JilinProvince which is “Analysis of the formation mechanism of Changbai Mountainnatural mineral water”(No.20100452). Based on the basic data collected, includinggeological, hydrogeological, meteorological, springs discharge and remote sensing, asystematic study was conducted on the formation mechanism of natural mineralwater in Jingyu national nature reserve from three aspects, which are regionalenvironment, groundwater circulation and water-rock interaction mechanism, with thethe method of combining qualitative and quantitative analysis and the means ofmutual authentication between field survey and laboratory analysis.(1) Analysis of regional environmentGIS and RS were applied to analyze the topography and land cover types of thestudy area. Basalt plateau in the study area has a flat terrain with average slope of3.02°and the major types of land are forest and swamp, with total area of190.9km2,accounting for91.1%of the study area. Swamps cover an area of38.5km2,accounting for18.4%of the study area, which are mainly located in the northeasternand southwestern of the study area. Projection pursuit cluster model was applied toassess the eco-environmental quality with12indicators. The result shows that theeco-environment of Jingyu national nature reserve is grade1. Special terraced terrain,lush forests and a large area of swamp, are all favorable conditions which providegood water conservation and supply conditions for mineral water and excellent andstable eco-environment is reliable ecological barrier which guarantees excellent waterquality. Basalt of the study area is classified as olivine basalt, mainly composed ofolivine, plagioclase and pyroxene, with50.20%average content of SiO2. Specialgeochemical background is the foundation of the chemical compositions of mineralwater. Basalt can be divided into many layers from up to down. Stomatal layers,Scoria layers, fissures and tectonic fractures constitute a complex storage anddrainage system for groundwater, forming a unique lava pore-fissures groundwatersystem. Permeability coefficient moves between0.23and0.50m/d, obtained from thepumping test for the test wells.Chemical types in the study area are mostly of HCO3-Ca-Mg or HCO3-Ca-Mgand keep stable, controlled by special geochemical and hydrogeological conditions.The concentration of silicic acid has s significant spatial variance structure in thestudy area. With increasing depth, concentration of silicic acid increases significantly,and the average concentration of silicic acid of springs in the central is slightly higherthan in the northeast, which indicates that groundwater runoff occurs mainly inshallow and central, while deep groundwater moves slowly.(2) Groundwater circulationIsotopic analysis of water samples from springs and test wells were carried out,including stable isotope D and18O and radioactive isotope3H. Most of the samplesscatter fall below the LMWL (local meteoric water line) of Changbai mountains andalong the local evaporation line, which shows that groundwater in the study areaoriginates from precipitation, even though little or a little evaporation occurs.Evaporation increases gradually from the southwest to the northeast, meanwhilevalues of18Oand Dat different depths have large difference, which reflectsdifferent recharge conditions. According to the calculation result of3H, the isotopicages of Kanglian and Beishang are the youngest and of ones of the central includingBaijiang are the oldest with3H isotopic age older than40a, while in the northeastisotopic ages are the lowest, younger than35a. Isotopic ages show a"Young-old-Young" U-shaped spatial distribution, which reflects the relativeindependence of groundwater system of each spring catchment.Based on77volcanoes in and adjacent to the study area and four construct pointsfound during the field investigation,10faults of under overburden were inferred using the methods of Fuzzy c-lines and L_MSCMO. Basalt formed by nulti-stage magmaticeruption covers the ancient basin forming a basin-shaped storage structure. Affectedby neotectonic movement, many tectonic fissures and rock broken rocks occurredalong old fractures, based on which some water-conducted paths were formed. It iswhy springs outcrop with shapes of clusters or lines. In this paper, acatchment-divided method considering synchronously the impacts of faults andsurface catchment basin was presented which was applied to the Shenglong-Jiulongspring-clusters and Julong-Feilong spring-clusters. The results show that, the areas ofcatchments of the two spring-clusters are26.9km2and45.5km2respectively, andcoefficients of rainfall infiltration rate calculated without considering other dischargeitems are0.317and0.332respectively. The dynamic changes of springs are mainlyaffected by precipitation and groundwater runoff. The daily flow is related with thecumulative rainfall. The fluctuation of average monthly flow has a lag time comparedto the rain, which is depended on the recharge environment.(3) The mechanism of water-rock interactionIn order to study the interactions between groundwater and water-bearing mediaincluding basalt, volcanic slag and soil interactions, static immersion and dynamicleaching experiments were designed. The interactions between groundwater and thethree media are mainly characteristic of the hydrolysis of the silicate and aluminumsilicate minerals.Concentrations of silicic acid increased with time in the early and graduallystabilized. The concentration of silicic acid in soil soaking is the highest, the second inthe scoria soaking and the lowest in the basalt soaking. Overall, pH values were beingon the rise throughout the experiment in the three soakuings, and respectivelystabilized in the final stage. Concentrations of ions except Cl-increased quickly in theearly and stabilized in the final stage. Concentration of Cl-in soil soaking is positivelycorrelated with pH values, because-NH2of soil has adsorption behavior to Cl-. Theamount of dissolved silicic acid in scoria soaking is higher, but the values of otheritems are the lowest of the three soakings, which is related to the precipitation-leaching environment. The unique soil environment of the study area hasan important influence on the formation of mineral solute components.The value ofpH of soil layer in the study area is about5.0~5.5. It not only is a important source ofsolute components and CO2, but also provides an environment with low pH, whichpromotes interaction between groundwater and basalt. Leaching experiments showedthat hydrolysises of vasalt and scoria have faster rate in flowing water than in stillwater. Water’s motion not only accelerates the convection and diffusion ofcomponents in solution, but also erodes the middle layer consist of secondaryminerals.Reverse and forward hydro-geochemical models were established based onPHREEQC and TOUGHREACT respectively. The main chemical reactions ofwater-rock interaction are hydrolysis of feldspar, pyroxene and forsterite along thegroundwater flow path, while feldspar is the dominate, from which silicic acid inaqueous solution derives. Ca-montmorillonite is the key aluminum silicate precipitate,while na-montmorillonite and kaolinite precipitate a little. Cation exchange occursstrongly which is characterized with that Ca2+of groundwater substitutes Na+ofbasalt.A conclusion can be easily drawn from the results of TOUGHREACT model,that fractures change the form of the groundwater flow field and acceleratedgroundwater circulation, which will correspondingly change water-rock interactionprocesses of groundwater systems and the concentrations and spatial distributions ofdissolved components eventually.更多还原