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基于银川平原的水文地质条件,对研究区的地下水环境综合指标与地下水化学类型进行了分析:EC值与DO值呈负相关关系,随着含盐量的增高,EC值增高,DO值减小;TDS与EC之间存在较好的正相关性,水中溶解的盐类越多,水的TDS 值越高,水的导电性越好,其电导率EC值越大。阳离子平均浓度由大到小为Na+>Ca2+>Mg2+>K+>NH+4,阴离子平均浓度由大到小为HCO-3>SO2-4>Cl-。研究区地下水类型以HCO3·SO4—Ca·Mg、HCO3·SO4—Ca·Na、HCO3·SO4—Na·Mg,以及SO4·HCO3—Na·Mg等类型为主。活度系数与离子强度呈反比,即离子强度升高导致水溶液中的离子浓度和电荷量升高,离子重新组合成溶质,导致离子活度系数下降。研究区内方解石最接近于平衡状态,可能存在于含水层环境中。对地下水环境综合指标和各组分浓度以及研究区水化学的形成环境进行分析可知:位于研究区中南部的65号点属于SO4·Cl—Na型水,受污染的可能性大;而在其南部的4、83、290号点,由于位于黄河灌溉区,受地表水的影响增强,地下水污染程度较65号点低。 相似文献
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战略性矿产勘查是近几年根据中国地勘管理体制的新变化和国家对矿产勘查工作的新要求提出的概念。本文从战略性矿产的基本内涵、战略性矿产资源勘查工作的性质与任务、战略性矿产资源勘查工作与传统矿产勘查工作的差异、战略性矿产资源勘查工作的管理体制与运行机制等几个方面进行了初步探讨,旨在明确其性质定位和目标任务,逐步建立国家出资的公益性地质工作与后续商业性矿产勘查工作良性互动、有机结合的有效机制,促进中国矿产勘查业全面、健康地发展。 相似文献
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环境调查研究表明,大武地下水水源地上游邻近的石化厂区出现严重的地下管道石油污染物持续泄漏现象。堠皋-柳杭地段地下水环境在成为集中污染地段的同时,水文地球化学环境也发生了迥然的变化:地下水中电子接受体溶解氧,NO3^-末检出,SO4^2-呈低值分布。这与地下水中存在微生物降解烃污染物的作用有关。其作用类型包括需氧降解,脱硝降解,脱硫降解以及有Fe^3+参与的降解作用。然而由于该地段需氧降解、脱硝降解、脱硫降懈以及有F3+参与的降解作用。然而由于废地段需氧降解、脱硝降懈难以进行,导致了生物降解污染物的速度降低 其研究意义是提高地下水中电子接受体的浓度.增强微生物的活性,以促进生物降解速度,将有利于含水层中这类污染物的清除。 相似文献
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根据峰峰矿区工业及民用建筑的岩土工程特征,以及在岩土工程勘察中所遇到的诸如由地形地貌产生的不良工程地质现象、特殊地质体等问题,认为在岩土工程勘察中,不仅要研究勘察场地的工程地质条件,而且要重视周围地质条件的宏观研究,同时建议建立岩土工程勘察档案数据库,为今后岩土工程勘察成果的使用、以及正确确定勘察手段奠定基础。 相似文献
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关于我国前寒武纪研究中几个重点问题的分析 总被引:1,自引:0,他引:1
陆松年 《前寒武纪研究进展》2002,25(2):65-72
在综合分析国内外前寒武纪地质研究动向的基础上,强调应加强研究的几个问题,其中包括在古大陆上进一步识别始太古代地壳和深化对古老地壳组成及特点的研究;对我国古元古界系统年代地层单位的南华系建系进行了分析;对孔兹岩系,榴辉岩相变质和 蛇绿岩等疑难地层和疑难地质事件时间维的确定应在进行微区测定的同时,深入对测年对象成因矿物学的研究;在前寒武纪超大陆和超大陆事件的研究过程中,应加强综合地层学方法的研究,立足于实际,重点解决我国几个古大陆之间的相互关系及它们在超大陆中的位置,同时强调微大陆体地史演化对研究造山带和古大陆复原工作的重要性;最后讨论了重大地质事件所引发的资源与环境效应。 相似文献
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生态系统营养离子循环及水化学演化的锶同位素示踪 总被引:7,自引:1,他引:7
综述了Sr同位素示踪生态系统离子循环和水化学演化的基本原理、主要内容和最新进展。着重介绍了Sr同位素在矿物风化速率研究、流域营养离子来源识别及其循环通量计算、地下水体化学成分演化机制的研究中的示踪应用;最后展望了Sr同位素在生物地球化学过程示踪上的潜在价值。 相似文献
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关于地下水库几个问题的探讨 总被引:38,自引:3,他引:38
赵天石 《水文地质工程地质》2002,29(5):65-67
本文重点探讨了地下水库的基本概念,分类和它的组成,包括由天然储水构造组成的地下水库库区,拦截地下径流的地下坝,地表拦水工程和引渗工程,地下水开发工程4个基本部分和其它组成部分,还探讨了地下水库的优势和问题。 相似文献
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关于成矿作用地球化学研究的几个问题 总被引:1,自引:0,他引:1
成矿作用地球化学是矿床地球化学的基础理论分支,属于应用基础类学科,以地球化学原理和方法研究造成元素沉淀富集形成矿床的地球化学作用的原因和机理。本文讨论了热液矿床成矿作用的几个问题。指出花岗岩与矿床类型之间是否存在相关性,即花岗岩是否具有成矿专属性仍然存在争论,需要继续探索。花岗岩类具有成矿潜力不等于这些花岗岩最终都能成矿。决定岩浆发生成矿作用的因素很多,其中岩浆分异作用过程和流体释放时间及其机制可能是决定成矿发生和矿床类型的关键,岩浆熔体中挥发组分及其行为可能是岩浆能否发生成矿作用的决定性要素,聚焦流体流动是成矿作用能否发生的关键环节,而自组织临界性和反馈作用决定了成矿效率和矿床的规模。 相似文献
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Hydrochemistry and solution rates in gypsum karst: case study from the Western Ukraine 总被引:1,自引:3,他引:1
The gypsum karst in the Western Ukraine spreads through a large territory covering more than 20,000 km2 and is represented by a range of stages (evolutionary types), from deep-seated through subjacent to entrenched. Correspondingly, hydrogeological settings of karst development, circulation patterns and chemical characteristics of groundwaters differ substantially between the respective areas. Based on 1,800 analyses, this paper summarises hydrochemistry of the gypsum-hosting Miocene aquifer. The majority of sampling has been performed in conjunction with a study regime of gypsum solution rates by means of standard tablets. In this study, which included 53 tablet stations representing varying conditions of water-rock interaction, 644 weight-loss measurements were made over the period 1984–1992. The highest rates are characteristic of entrenched karst although active dissolution is localised along well-defined sinking streams with short underground courses, rare vertical percolation paths and the water table. Lower but still quite substantial rates are characteristic of subjacent and deep-seated (confined) karst. However, the overall dissolution removal is greater due to higher flow through the gypsum and the larger area of rock-solvent contact. The results are generalised in order to derive the approximate solution rates characterising major situations and to be suitable for modeling purposes. 相似文献
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The demand for water resources in the area south of the Dead Sea due to continued development, especially at the Arab Potash
Company (APC) works necessitates that water quality in the area be monitored and evaluated based on the local geology and
hydrogeology. The objective of this paper is to provide information on the past and present status of the main aquifers under
exploitation or planned for future development. Two main aquifers are discussed: the Safi water field, presently being operated,
and the Dhiraa water field, which is being developed. The aquifer developed in the Safi water field is shallow and fed by
the Hasa fault system, which drains a significant portion of the Karak mountains. This aquifer seems to be well replenished
within the core, where no obvious long-term degradation in water quality can be identified. However, in the low recharge areas
within the distal portions of the alluvial fan, there has been a degradation in water quality with time. The degradation is
caused by the dissolution of the Lisan Marl, which is present at the outskirts of the fan system, based on hydrochemistry
of water in the wells. The Dhiraa field is a deep (800–950 m) aquifer drilled specifically for the extraction of brackish
water present in the Kurnub aquifer. Available data indicate that there are at least three distinct water types within this
field. These water types are variable in quality, and there may be potential for mixing of these waters, thus affecting the
quality of the freshest waters presently available. Tritium and oxygen isotope analysis indicate that the water is old and
possibly nonrenewable.
Received: 24 July 1995 · Accepted: 26 September 1995 相似文献
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Maozhong Min Xinjian Peng Xianlin Zhou Haiming Qiao Jinping Wang Li Zhang 《Journal of Geochemical Exploration》2007,93(2):91-108
Groundwaters and surface water in the Shihongtan sandstone-hosted U ore district, Xinjiang, NW China, were sampled and analyzed for their major-, and trace element concentrations and oxygen, hydrogen, boron and strontium isotope compositions in order to assess the possible origins of the waters and water–rock interactions that occurred in the deep aquifer system. The waters in the study district have been grouped into three hydrochemical facies: Facies 1, potable spring-water, is a pH neutral (7.0), Na–Ca–HCO3 type water with low total dissolved solids (TDS; 0.2 g/l, fresh) and has δ18O of − 8.3‰, δD of − 48.2‰,δ11B of 1.5‰, and 87Sr/86Sr of 0.70627. Facies 2 groundwaters are mildly acidic to mildly alkaline (pH of 6.5–8.0, mean 7.3), Na–Ca–Mg–Cl–SO4 type waters with moderate TDS (8.2 g/l–17.2 g/l, mean 9.3 g/l, brackish) and haveδ18O values in the − 5.8‰ to − 9.3‰ range (mean − 8.1‰), δD values in the − 20.8‰ to − 85.5‰ range (mean − 47.0‰),δ11B values in the + 9.5‰ to + 39.1‰ range (mean + 17.1‰), and 87Sr/86Sr values in the 0.70595 to 0.70975 range (mean 0.70826). Facies 3, Aiting Lake water, is a mildly alkaline (pH = 7.4), Na–Ca–Mg–Cl–SO4 type water with the highest TDS (249.1 g/l, brine) and has δ18O of − 2.8‰, δD of − 45.8‰,δ11B of 21.2‰, and 87Sr/86Sr of 0.70840. The waters from the study district show a systematic increase in major, trace element and TDS concentrations and δ11B values along the pathway of groundwater migration which can only be interpreted in terms of water–rock interaction at depth and strong surface evaporation. The hydrochemical and isotopic data presented here confirm that the groundwaters in the Shihongtan ore district are the combined result of migration, water–rock interaction and mixing of meteoric water with connate waters contained in sediments. 相似文献
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Hydrochemistry of urban groundwater in Seoul, South Korea: effects of land-use and pollutant recharge 总被引:1,自引:0,他引:1
Byoung-Young Choi Seong-Taek Yun Soon-Young Yu Pyeong-Koo Lee Seong-Sook Park Gi-Tak Chae Bernhard Mayer 《Environmental Geology》2005,48(8):979-990
The ionic and isotopic compositions (δD, δ18O, and 3H) of urban groundwaters have been monitored in Seoul to examine the water quality in relation to land-use. High tritium contents
(6.1–12.0 TU) and the absence of spatial/seasonal change of O–H isotope data indicate that groundwaters are well mixed within
aquifers with recently recharged waters of high contamination susceptibility. Statistical analyses show a spatial variation
of major ions in relation to land-use type. The major ion concentrations tend to increase with anthropogenic contamination,
due to the local pollutants recharge. The TDS concentration appears to be a useful contamination indicator, as it generally
increases by the order of forested green zone (average 151 mg/l), agricultural area, residential area, traffic area, and industrialized
area (average 585 mg/l). With the increased anthropogenic contamination, the groundwater chemistry changes from a Ca–HCO3 type toward a Ca–Cl(+NO3) type. The source and behavior of major ions are discussed and the hydrochemical backgrounds are proposed as the basis of
a groundwater management plan. 相似文献
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Abhay Kumar Singh G. C. Mondal P. K. Singh S. Singh T. B. Singh B. K. Tewary 《Environmental Geology》2005,48(8):1014-1028
Water samples collected from the six reservoirs of Damodar River basin in pre- and post-monsoon, have been analysed, to study
the major ion chemistry and the weathering and geochemical processes controlling the water composition. Ca, Na and HCO3 dominate the chemical composition of the reservoir water. The seasonal data shows a minimum concentration of most of the
ions in post-monsoon and a maximum concentration in pre-monsoon seasons, reflecting the concentrating effects due to elevated
temperature and increased evaporation during the low water level period of the pre-monsoon season. Water chemistry of the
reservoirs strongly reflects the dominance of continental weathering aided by atmospheric and anthropogenic activities in
the catchment area. Higher concentration of SO4 and TDS in Panchet, Durgapur and Tenughat reservoirs indicate mining and anthropogenic impact on water quality. The high
contribution of (Ca+Mg) to the total cations, high concentration of dissolved silica, relatively high (Na+K)/TZ+ ratio (0.3) and low equivalent ratio of (Ca+Mg)/(Na+K) suggests combined influence of carbonate and silicate weathering.
Kaolinite is the possible mineral that is in equilibrium with the water, implying that the chemistry of reservoir water favours
kaolinite formation. The calculated values of SAR, RSC and sodium percentage indicate the ‘excellent to good quality’ of water
for irrigation uses. 相似文献
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Giorgio Pilla Elisa Sacchi Gianmaria Zuppi Giovanni Braga Gianfranco Ciancetti 《Hydrogeology Journal》2006,14(5):795-808
A multicriteria approach in studying hydrodynamics of a multilayer aquifer system has been used in the Lomellina region (Northern Italy). It involves the reconstruction of the hydrogeological framework coupled to the definition of the hydrochemical and isotopic features of the aquifers. A shallow phreatic aquifer, reaching depths of about 60–80 m from the surface, and deeper aquifers containing confined groundwater, were distinguished. Groundwater generally shows mineralisation decreasing with depth; dissolved ions depict calcium-bicarbonate hydrochemical facies and stable isotopes define the recharge mechanisms, the origin of groundwater, and the hydraulic confinement of deep aquifers. The phreatic aquifer is fed by local infiltration and by streams and irrigation channels. Tritium and Carbon-14 groundwater dating indicate long residence times (on the order of thousands of years) for confined aquifers. The confined aquifers show essentially passive hydrodynamic conditions and maintain a higher piezometric level than the phreatic aquifer. This inhibits the possibility of recent water penetrating far below the surface. The hydrogeological setting of the Lomellina region displays features which are common to other sectors of the Po plain. As a consequence, the results of this study, although conducted on a restricted area, are highly illustrative of groundwater hydrodynamics in large sedimentary aquifers. 相似文献
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随着地籍管理科技发展,铁路用地地籍管理在引入国家大地统一坐标系的测量技术手段的同时,为满足铁路用地线状分布特点和Et常管理的需要,仍然保留了独立坐标系统。而铁路运营设备的不断更新和技术装备的不断提高,铁路线路设备发生了较多拨移、变线或改道,作为确认铁路地界线位置的基准线,铁路线路的变化,对快速准确地查找铁路地界线产生了直接影响。为此,针对铁路用地参照坐标的变化情况及调整方法进行了深入调查研究,提出了可行性建议。 相似文献