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1.
苗迎  孔祥胜  宋朝静 《中国岩溶》2015,34(3):228-233
为了深入研究南宁市区地下水水化学特征、水质情况及地下水质量演变的主要水化学过程,文章采集南宁市区22组孔隙水和7组岩溶水,检测pH值、阴阳离子、溶解性总固体(TDS)和总硬度等化学指标,探讨地下水水化学特征和形成机制。结果表明:研究区孔隙水和岩溶水pH平均值均小于7,两种水TDS和总硬度基本一致,主要的阴离子(HCO3-、Cl-、SO42-)中含量最高的是HCO3-,平均分别为68.08 mg/L和106.68 mg/L;对于阳离子(Ca2+、Mg2+、K+、Na+),研究区孔隙水和岩溶水均表现为Ca2+≥Na+>Mg2+>K+,其中Ca2+的平均含量分别为24.04 mg/L和31.34 mg/L;地下水化学成分主要通过风化-溶滤作用与混合作用形成,地下水水化学类型为HCO3--Ca2+型水;地质环境背景是地下水pH值普遍偏低的主要原因,人类活动对地下水的影响越来越重要,pH值和水化学类型改变均与经济发展、人口增加、工矿企业增加等人类活动密切相关。   相似文献   

2.
芙蓉洞洞穴水离子浓度和元素比值变化特征及其环境意义   总被引:5,自引:3,他引:2  
通过对芙蓉洞2006年3月—2009年2月期间泉水和洞穴滴水、池水的地球化学指标监测,结合当地的器测数据,初步认为洞穴滴水的Sr2+、Ca2+、Mg2+浓度及其比值既取决于环境降水和温度的变化,也受到上覆岩土作用的影响。芙蓉洞外山上的6#泉水Ca2+平均浓度为45.81mg/L,洞内1#、3#滴水Ca2+的平均浓度64.59mg/L,2#和4#池水中由于Ca2+沉积,浓度下降到24.74mg/L,下降了大约61.7%。Mg2+和Sr2+的浓度在泉水、滴水和池水中的变化规律与Ca2+基本一致。各种水体中Cl-的浓度变化幅度较小,平均浓度为1.72±0.2mg/L。岩溶水与基岩作用时间长短以及运移过程中Ca2+的前期沉积作用对各元素与离子含量变化具有重要作用。旱季Ca2+的前期沉积作用和雨季基岩的溶蚀及雨水的稀释作用主导着岩溶水中Mg/Ca与Sr/Ca的变化,这些指标能对干旱和洪涝等极端气候事件做出响应。   相似文献   

3.
发源于唐古拉山山脉的河流在青藏高原地区具有流域面积大、径流距离长以及流量大等特点,与喜马拉雅山地区河流共同组成全球河源区最高的水流系统。它们的物理与化学侵蚀在很大程度上代表了在全球气候变化的条件下,大陆的侵蚀作用所发生的变化,即大陆与海洋的物质运移和平衡。发源于唐古拉山北坡的长江源头主要支流楚玛尔河与沱沱河的物理化学特点是溶解的化学成分含量较高,一般为10.66~410.81mmol/L,主要阳离子为Na+、Ca2+和Mg2+,占阳离子总量的97%以上。Ca2+/Na+、Mg2+/Na+、K+/Na+的比值较低,87Sr/86Sr值为(0.708954±0.000020)~(0.711860±0.000011),表明唐古拉山北坡的河水成分以蒸发岩类溶解为主。发源于唐古拉山南坡的怒江源头以及雅鲁藏布江及其支流等的主要阳离子为Ca2+、Mg2+、Na+,占阳离子总量的97%以上。Ca2+/Na+、Mg2+/Na+、K+/Na+的比值较高,87Sr/86Sr值为(0.705534±0.000016)~(0.722856±0.000014),表现为以碳酸盐岩和硅酸盐岩的溶解为主。长江河源区河水中主要化学成分来自蒸发岩,其中Na+和Cl-在河流水化学成分中占比例最大,经计算,唐古拉山北坡长江源头地区的物理侵蚀率为77kg/(km.2a),蒸发岩的化学侵蚀率为49~72.7t/(km.2a),碳酸盐岩的化学侵蚀率为15~20t/(km.2a),硅酸盐岩的化学侵蚀率为2~5t/(km.2a);南坡物理侵蚀率为34kg/(km.2a),碳酸盐岩的化学侵蚀率为25~30t/(km.2a),硅酸盐岩的化学侵蚀率为7~10t/(km.2a)。这些特征反映出北坡高寒干旱环境下河流蒸发岩的化学侵蚀作用较强,南坡碳酸盐岩和硅酸盐岩的化学侵蚀作用大于北坡。  相似文献   

4.
为研究汉中盆地地下水的水化学特征及成因,在丰水期共采集56件潜水样品,综合运用数理统计、相关性分析、Piper三线图、Gibbs模型和离子比等方法,分析了汉中盆地地下水的水文地球化学特征、各化学参数的空间变化规律、主要离子的控制因素及来源。结果表明,汉中盆地地下水阳离子以Ca2+为主,阴离子以HCO3–为主。从离子空间变化规律上来看, K+波动最为剧烈,且从中下游开始逐渐降低,Cl−和Na+变化规律一致,呈波动变化;HCO3−、Ca2+、Mg2+以及SO42−的从中上游至中下游含量逐步降低,至下游含量增加;TDS值为128.5~590 mg/L,平均值为282.67 mg/L,在中下游含量明显增加;pH平均值为7.17,为弱碱性,在中上游波动剧烈,至下游逐渐降低。地下水水化学类型以HCO3–Ca和HCO3–Ca·Mg型为主,受碳酸盐岩和硅酸盐岩的溶解共同控制,阳离子交替吸附作用较弱,Na+和K+主要来源于钾长石、钠长石等硅铝酸盐矿物的溶解和部分盐岩的风化溶解,Ca2+除来自碳酸盐岩的溶解外,还有大量硅酸盐岩的溶解;方解石及少量白云石等碳酸盐岩的风化溶解对Mg2+和HCO3−贡献较大。查明汉中盆地地下水水化学特征及成因机制,可为汉中地区地下水饮水安全提供有力科学依据。  相似文献   

5.
为了研究赤泥中氟向下运移过程中的影响因素,根据堆场周围的水文地质条件,设计了7组动态淋溶试验,并对试验数据进行了灰色关联度分析。结果表明,排放7天后的赤泥其表面下700 mm处的温度仍达78℃,而刚排放到堆场的冲灰水温度更高,可达87.5℃,高温赤泥和冲灰水有利于氟的迁移;赤泥的pH值为10.29~11.83,浸出液的pH值为12.00~13.20,碱性很大,致使氟易随水迁移;赤泥的其它污染组分,如总硬度、Cl-、SO42-、K+、Na+、Ca2+、Mg2+,均对氟的迁移有一定的影响,且Na+、SO42-和Ca2+为主要控制因素,即溶液中Na+、SO42-、Ca2+含量越高,赤泥中的F-离子越易淋出。   相似文献   

6.
位于云南省云龙县的羊吃蜜温泉自巨厚灰岩溶隙向外流出。温泉区沿河谷分布有第四系砂卵石,下伏地层为二叠系—三叠系碳酸盐岩。泉水共有泉眼3个,水温为356~359 ℃,流量约025 m3/s,pH值63~65,总溶解性固体(TDS)为0982~1116 g/L,F-含量为086~192 mg/L,偏硅酸为24~242 mg/L。泉水中的主要阳离子为Na+、K+、Ca2+和Mg2+,主要阴离子为SO42-、HCO3-和Cl-,水化学类型为HCO3·SO4 Ca型。氢、氧稳定同位素显示,温泉热水来源于大气降水;估算的热水补给高程为2 500 m左右;地下热储温度为60~70 ℃;地下热水循环深度约为1 255 m。羊吃蜜温泉地处云南兰坪盆地红色含盐地层中突起的石灰岩分布区,地下水在补给区获得大气降水入渗补给后沿巨厚灰岩含水层经历深循环获得大地热流加热后上涌在河谷流出地面,是侵蚀岩溶低温温泉。  相似文献   

7.
中国主要类型锑矿床矿物包裹体地质地球化学   总被引:4,自引:1,他引:3  
讨论了中国主要类型锑矿床矿物包裹体形态、大小、气液比值、包裹体爆裂温度、均一化温度和盐度.认为锑矿床中辉锑矿最佳形成温度为180℃~220℃,盐度变化范围为(5~10) wt%NaCl.矿物包裹体成分变化较大,均以H2O为主,气相成分主要为CO2,液相成分中以Na+,Ca2+为主,K+、Mg2+次之,K+/Na+比值一般小于1,Ca2+/Mg2+比值一般大于1,说明锑矿床的成矿流体液相组分以H2O、Na+、Ca2+、F-、Cl-为主,气相组分以CO2为主.根据矿物包裹体中某些成分的相关性,可判别矿床之间的关系,指导找矿勘查工作.  相似文献   

8.
样品测试是研究岩溶区水工环问题的重要手段。岩溶区交通不便利、样品运输困难以及测试单位处理样品不及时,导致样品测试存在不同程度的滞后,现有研究还不能有效解释"测试滞后"对岩溶水样性质有何影响。为此,本文以云南宣威市一典型岩溶泉水为研究对象,通过离子色谱仪、原子发射光谱仪等测试手段,对同一时间点采集的泉水样品按照时间序列对K+、Na+、Ca2+、Mg2+、Cl-、SO2-4、HCO-3、pH、NO-3、CO2(fs)共10项指标进行对比实验,探讨"测试滞后"对岩溶水样性质的影响。结果表明:岩溶水样放置过程中,各指标A类标准不确定度为0. 02~1. 83,HCO-3、Ca2+不确定度值显著高于其他指标; Shapiro-Wilk正态性检验结果显示pH、K+、Mg2+、Cl-、NO-3服从正态分布;随着时间变化,各指标相对偏差变化范围0%~57. 38%,其中pH、Ca2+、SO2-4、NO-3的相对偏差在允许误差范围之内; 10项指标均值含量与变异系数总体呈显著负相关性(Spearman相关系数为-0. 709,P 0. 05),变异系数为Na+ K+ CO2(fs) Mg2+ Cl-SO2-4 Ca2+ HCO-3 p H NO-3,揭示测试滞后对不同指标的影响程度不同,其中对质量分数低的指标影响尤为突出。在整个实验期间内,水样水质变化可分为5个阶段:以各项指标未出现明显变化的初期稳定阶段(0~3d),以Na+、K+、Mg2+三项指标出现显著变化的初步变化阶段(3~5d),以多项指标发生较为显著变化的混合变化阶段(5~17d),以微生物作用为主的细菌潜在影响阶段(17~35d),以水质趋于稳定的相对平衡阶段(35~75d),其中"细菌作用"和"碳酸平衡作用"是岩溶水样放置过程中存在的两个重要作用机制。研究结果可为提高岩溶水样测试质量提供科学指导。  相似文献   

9.
建立了电感耦合等离子体发射光谱法(ICP-AES)同时测定碳酸盐型、硫酸盐型、氯化物型三种类型卤水中Li、Na、K、Ca、Mg、B、S、Cl等高低含量元素的分析方法。选择仪器最佳的工作条件为射频功率1400W,炬管位置位于-3,载气流量0.60 L/min。确定了各元素测定谱线,使用ICP-AES的双向观测模式、轴向观测模式测定Li、Ca、B、S、Cl以及低含量的K、Mg,径向观测模式测定高含量的Na、K、Mg,可确保卤水中不同含量的元素同时检出。Li、Na、K、Ca、Mg、B、S的检测下限为0.07~3.00 mg/L,Cl的测定下限为165mg/L。方法精密度(RSD,n=10)均小于5%,回收率为92.4%~109.7%。其中Na、K、Mg、S、Cl测定结果与传统方法测定结果基本吻合。  相似文献   

10.
根据威宁草海第四纪窑上组沉积物主量元素和REE特征,探讨沉积物物源特征、气候演变情况、沉积物堆积控制因素。结果表明:Al、Mg、Ca、K、Na和Ti的含量变化在剖面上一致,它们的相关系数很高(0.522~0.985)。Fe含量和Mn含量呈正相关形式,与Al、Mg、Ca、K、Na和Ti呈负相关。Fe2O3含量在土黄色粘土的铁质层很高(42.86%~50.57%)。样品中REE球粒陨石标准化配分模式与贵州土壤、贵州碳酸盐岩风化壳配分模式很相似,与峨眉山玄武岩配分模式不一致,但其含量略低于贵州碳酸盐岩风化壳的含量;沉积物主要来源于碳酸盐岩,且碳酸盐岩强烈风化成土作用使REE超常富集,在剖面上呈现高ΣREE(平均219.38μg/g)。通过Mg/Ca、MgO/Al2O3、(CaO+K2O+Na2O)/Al2O3、(Fe2O3+Al2O3)/(MgO+CaO)、(K+Na+Ca+Mg)/(Fe+Mn)、(Al+Fe+Mn)/(K+Ca+Mg)和(MgO+Na2O+CaO)/Al2O3等气候指标研究,表明在草海窑上期为湖泊沉积时期,气候经历了由温暖湿润向冷干的转变。同时,认为物源性质、构造运动、气候等共同控制该区沉积物形成。  相似文献   

11.
Two springs (Cuihua Spring, Shuiqiuchi Spring) in Cuihua Mountain of the Qinling Mountains were observed and sampled monthly during 2004 and 2005 to trace their physical properties and chemical compositions with seasons. Although both pH values and cation (Ca2+, Mg2+, K+, and Na+) contents of Cuihua Spring are higher than those of Shuiqiuchi Spring, seasonal variations in both springs are obvious. The pH values of both spring waters are between 5.69 and 6.98, lower than that of rainwater during summer and autumn. From January to November, the pH values of both springs similarly vary from high to low and then to high again. Variations in electric conductivities of two spring waters are contrary, although their electric conductivities are positively correlative with the cation content respectively. This can be attributed to different water sources of the two springs or different acidic rocks they passed. The contents of HCO3 , Ca2+, Mg2+, K+, and Na+ are low, indicating a low silicate weathering that the strata in this district are mainly composed of granite and schist of quartz and mica. Differing from change in spring water in karst regions of South China where abundant precipitation and dilution of rainwater cause low pH and electric conductivity in summer and autumn, the seasonal variations in the pH values and the electric conductivities of two springs in Qinling Mountains are attributed to seasonal changes in CO2 produced by microorganisms’ activity in soil within respective year, rather than rainfall. The microorganisms’ activity in soil produces more CO2 during summer and autumn. Therefore, the water nature of springs in silicate regions chiefly reflects the seasonal changes of CO2 produced by the microorganisms in soil.  相似文献   

12.
西安灞河流域现代岩溶作用与CO2吸收量   总被引:5,自引:2,他引:3       下载免费PDF全文
本文探讨了灞河流域岩溶特征、CO2估算方法和CO2吸收量。观测资料表明,灞河流 域河水中pH值在冬春季高,夏秋季低,而HCO3含量通常与pH相反。河水和黄土地下水中 pH值、HCO3等化学成分含量与北方南部石灰岩区岩溶水基本相同,表明该区现代岩溶作用 明显,黄土地层也在不断吸收CO2,并对全球碳循环有重要影响。雨水富含CO2,其中约有 82%的CO2被岩溶过程吸收,18%左右的随河水流失。根据一个流域CO2输入量和输出量,可 以计算岩溶过程中 CO2吸收量。计算表明,灞河流域现代岩溶过程中每年吸收的 CO2约为5632.8t。  相似文献   

13.
Conspicuous sulfide-rich karst springs flow from Cretaceous carbonates in northern Sierra de Chiapas, Mexico. This is a geologically complex, tropical karst area. The physical, geologic, hydrologic and chemical attributes of these springs were determined and integrated into a conceptual hydrogeologic model. A meteoric source and a recharge elevation below 1,500 m are estimated from the spring-water isotopic signature regardless of their chemical composition. Brackish spring water flows at a maximum depth of 2,000 m, as inferred from similar chemical attributes to the produced water from a nearby oil well. Oil reservoirs may be found at depths below 2,000 m. Three subsurface environments or aquifers are identified based on the B, Li+, K+ and SiO2 concentrations, spring water temperatures, and CO2 pressures. There is mixing between these aquifers. The aquifer designated Local is shallow and contains potable water vulnerable to pollution. The aquifer named Northern receives some brackish produced water. The composition of the Southern aquifer is influenced by halite dissolution enhanced at fault detachment surfaces. Epigenic speleogenesis is associated with the Local springs. In contrast, hypogenic speleogenesis is associated with the brackish sulfidic springs from the Northern and the Southern environments.  相似文献   

14.
在2001年秋季对贵州省荔波县茂兰国家喀斯特森林公园林地、草地植被下土壤CO2呼吸释放及岩溶表层泉水HCO3及其δ13C值的变化进行了日动态的野外监测,表明岩溶系统中土-气-水界面间存在着碳交换的日动态变化以及所伴随的同位素交换的变化,这种变化与土温的日动态有密切的关系。林地植被显示了平抑这种日动态幅度的效应,而草地植被则显示响应于温度变化的较灵敏的动态变化。这种短尺度的变化构成了表层岩溶系统对外界条件的灵敏响应,进一步揭示了在生物作用下岩溶地质作用在碳循环过程及其同位素交换上的灵敏性和动态性。其不同植被系统下的日动态差异在解释岩溶沉积记录和讨论岩溶作用与碳循环时值得充分注意。  相似文献   

15.
Precipitation, soil and spring waters from an outlier of Chalk were analysed over a one year period for field pH, and contents of Ca+2, Mg+2, HCO3? and other dissolved solids. Measured soil log PCO2 (atm) varied between a minimum of ?2.60 and maximum of ?1.46, and could be predicted from measurements of soil temperature. Soil waters evolved under open system conditions with respect to soil CO2, and were undersaturated with calcite during the winter recharge period.The chemistry of the springs is related to their topographic position. Group 1 springs, located below a feather edge of chalk, had both their minimum and maximum PCO2s predicted by the soil CO2 data, suggesting open system CO2 evolution. Group 2 springs, located along the scarp slope had minimum PCO2s predicted by the soil data, but maximum PCO2s which could only be explained by a closed system evolution from the maximum soil CO2 observed. Group 1 springs were close to calcite saturation, whereas Group 2 springs were significantly undersaturated with calcite. The two groups could be identified by linear discriminant analysis of measured Ca2+, pH and HCO3? concentrations.  相似文献   

16.
A study was conducted in seven geothermal springs located in Bakreswar, District Birbhum, West Bengal, India, in order to assess numerous geochemical processes which were responsible for chemical composition of thermal and mineralized water. The study area lies over the Sone, Narmada, and Tapti lineament of Precambrian Chotanagpur Gneissic Complex. Water chemistry has been carried out based on reaction stoichiometry and geo-statistical tools to identify geochemical process. Piper and Gibbs diagram suggest that the spring water belongs to Ca2+-Mg2+-HCO3??+?CO32? water type and are controlled by rock dominance. Dissolution and precipitation of calcite, dolomite, gypsum, and fluorite minerals were identified as principle source of major ions in seven geothermal spring water. Principle component analyses revealed that major ions of spring water are derived from geogenic processes such as weathering, dissolution, and precipitation of various minerals. Overall results suggest that major ions of the spring’s water are derived from natural origin because no evidence of anthropogenic sources was observed during the study period. This study has also revealed that water quality of spring’s water is not suitable for drinking purposes and quite suitable for irrigation because of high abundance of Na+, K+, Cl?, and HCO3? ions.  相似文献   

17.
《Applied Geochemistry》2006,21(2):289-304
Mineral springs from Daylesford, Australia discharge at ambient temperatures, have high CO2 contents, and effervesce naturally. Mineral waters have high HCO3 and Na concentrations (up to 4110 and 750 mg/L, respectively) and CO2 concentrations of 620–2520 mg/L. Calcium and Mg concentrations are 61–250 and 44–215 mg/L, respectively, and Si, Sr, Ba, and Li are the most abundant minor and trace elements. The high PCO2 of these waters promotes mineral dissolution, while maintaining low pH values, and geochemical modelling indicates that the CO2-rich mineral water must have interacted with both sediments and basalts. Amorphous silica concentrations and silica geothermometry indicate that these waters are unlikely to have been heated above ambient temperatures and therefore reflect shallow circulation on the order of several hundreds of metres. Variations in minor and trace element composition from closely adjacent spring discharges indicate that groundwater flows within relatively isolated fracture networks. The chemical consistency of individual spring discharges over at least 20 a indicates that flow within these fracture networks has remained isolated over long periods. The mineral water resource is at risk from mixing with potentially contaminated surface water and shallow groundwater in the discharge areas. Increased δ2H values and Cl concentrations, and lower Na concentrations indicate those springs that are most at risk from surface contamination and overpumping. Elevated NO3 concentrations in a few springs indicate that these springs have already been contaminated during discharge.  相似文献   

18.
This paper aims to propose a quality profile of springs of the study area for irrigation. In the present study, fifty-four springs in Almora have been identified from rural as well as urban localities for calculation of irriga- tional water quality parameters during pre-monsoon, monsoon and post-monsoon, 2008. Spring water samples are collected and analyzed for pH, electrical conductivity (EC), total dissolved solids (TDS), Na+ , K+ , Ca2+ , Mg2+ , HCO3- , Cl- , and SO42- . Different irrigation quality parameters viz. salinity, sodium adsorption ratio (SAR), soluble sodium percentage (SSP), residual sodium carbonate (RSC), magnesium hazards (MH) and permeability index (PI) are calculated for the evaluation of spring water quality for irrigation purposes. All springs are found excellent to good based on irrigation quality parameters. Based on Wilcox diagram, about 98% of the water resources are grouped as C1S1 (low-low) and C2S1 (medium-low) classes, so springs are suitable for normal irrigation.  相似文献   

19.
Fragmentary information of considerable interest in Zabaykal'ye [east of Lake Baykal]. This paper reports on cold spring waters which contain high concentrations of carbon dioxide and relatively low content of Ca2+, Mg2+, Na+, and K+ anions. In one instance gas issues from a funnel shaped cavity in Paleozoic porphyrites (Vitlaus) and in another instance from joints in lower Mesozoic granite aplites. Artesian waters containing over 2500 mg/L of free carbon dioxide were encountered at a flow rate of 15 L/sec under a hydrostatic flowing head of 9 m near the Lipaki ‐ 1 spring 30 km from the village of Vershino‐Darasun, Chita Oblast. ‐ ‐B. N. Cooper.  相似文献   

20.
Variability of aquatic chemistry in central Guizhou karst region, China   总被引:1,自引:1,他引:0  
It is necessary to understand the aquatic chemical characterstics of natural surface fresh water for water quality assessment.The chemical data from different kinds of water in the central Guizhou karst area showd that spring water from carbonate rock cracks(crack-water)is of neutrality or meta-alkalinity and [C] Ca II type.The amounts of all ions and the concentrations of HCO3^- and Ca^2 were higher in the autumn than in the spring,The crack-water was influenced by the infiltration of surface water in the process of erosion and /or trans-portation with decreasing HCO3 and increasing pH,SO4^2-,Cl^-,K^ and Na^ during running in a certain distance on the land surface .In particular,the chemical compositions of the waters at Tianxingqiao(upper-stream),Shuiliandong(mid-waterfall)and Luoshuitan(down-pool)near the Huangguoshu Waterfall were much different from those of the crack-water.The concentration of SO4^2-,Na^ ,Fe^3 and NO3^- varied closely with seasons.The CaCO3 deposited violently with CO2 release in the spring ,In Lake Hongfeng the HCO3^-/SO4^2- equivalent ratios were only 2.1-2.4 ,but Ca^2 /Mg^2 up to 2.4-4.2.The Cl^- concentration increased by a factor of 1 and Na^ by order of magnitude relative to the spring water.These indicated the increase in artificial pollutant discharge in the Lake Hongfeng watershed.In addition,Proewater in the soils covering carbonate rocks belongs to strongly mineralized water,The obvious differences in water quality were controlled by carbonate deposition,sulphate mineralization and nitrogen fixation as well as ammonification.It is indicated thaty the chemical compositions in the waters from the karst region were unstable and changeable.  相似文献   

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