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1.
This work present results of the hydrochemical and isotopic studies on groundwater samples from the study area. Chemical and
environmental isotope data are presented and discussed in terms of the origin of dissolved species and of groundwater. All
of the investigated groundwater are categorized into two chemical types: low and relatively high mineralized waters type.
Interpretation of chemical data, based on both thermodynamic calculations and stability diagrams, suggests that the chemical
evolution of groundwater is primarily controlled by water-rock interactions. Interpretation of 18O and 2H suggests that the recharge of the investigated groundwater may result from differents mechanisms 相似文献
2.
PHREEQC在研究地浸溶质迁移过程中的应用 总被引:6,自引:1,他引:5
应用地球化学模式PHREEQC,揭示地浸过程中溶质迁移的存在形式及各种形式之间的转化关系。通过计算饱和指数,确定溶质水解沉淀的水文地球化学条件临界值。 相似文献
3.
Helmut Kerndorff Stephan Kühn Thomas Minden Dagmar Orlikowski Thomas Struppe 《Environmental Geology》2008,55(2):291-301
The aim of this research project is to identify, characterize and quantify natural attenuation (NA) processes in groundwater
affected by emissions of abandoned waste disposal sites in Berlin-Kladow/Gatow, Germany. It is part of the funding priority
called KORA established by the Federal Ministry for Education and Research (BMBF) to explore the extent to which NA can be
used for remedial purposes for varied forms of soil and groundwater contamination. Information on the emission behaviour of
individual parameters is generated on the basis of hydrogeochemical comparison of 20 years old and new data. Using groundwater-modelling
and CFC-analysis, information on the transport and retention of pollutants in groundwater is compiled. The microbial colonization
of contaminated aquifers is characterized by molecular biological methods [polymerase chain reaction (PCR) and denaturing
gradient gel electrophoresis (DGGE)] to differentiate between contaminated and not contaminated zones. 相似文献
4.
Mohammad R. Al-Agha 《Environmental Geology》2005,47(7):898-906
Groundwater is a critical resource in Khanyounis city as it is the main source of water. The aquifer has deteriorated to a high degree, during the last two to three decades, in quality and quantity. More than 90% of the population get their drinking water from brackish water desalination plants. Fifteen domestic wells were sampled in 2002 to probe the hydrogeochemical components that influence the water quality. Na, K, Ca, Mg, Cl, SO4, NO3, and HCO3 were analyzed. The data were statistically treated and plotted on the Piper diagram. A hydrogeochemical numerical model for carbonate minerals was constructed using the PHREEQ package. The results show that the groundwater is polluted with Cl, from seawater, and NO3, sourced from fertilizers and sewage. The regression analysis shows that there are three groups of elements that are significantly and positively correlated. Na–Cl signature and plot show that seawater intrusion is advancing into the aquifer. The main hydrochemical facies of the aquifer (Na+K–Cl+SO4), represents 60% of the total wells. Whereas 32.3% of the wells are located in the no pair up and no pair down fields on the Piper diagram. Calcite, dolomite, and aragonite solubility were assessed in terms of the saturation index where they show positive values indicating supersaturation. The hydrogeochemical behavior is rather complicated and is affected by anthropogenic and natural parameters. 相似文献
5.
Medium-temperature thermal waters in the Mura basin occur in hydrogeological systems different in age, burial depth, temperature, porosity and permeability, and the presence of free carbon dioxide which penetrates through the fractures from pre-Tertiary basement. The waters commonly belong to sodium-bicarbonate hydrogeochemical facies, but may have significantly different amounts of total dissolved solids, including trace elements. Thermal waters occurring in low-permeable, well-compacted and moderately fractured Tertiary sediments older than Upper Pliocene are the richest in trace elements, although their abundance may be very variable from one aquifer to another. The ratios of major alkaline and alkaline earth elements (Na, K, Ca) and trace elements (Li, Rb, Cs, Ba, Sr) commonly show relative enrichment in highly mineralised waters with respect to the waters with lower mineralisation. Rare earth elements (REEs) and Y show only minor fractionation in the highly mineralised waters, whereas in the waters with lower mineralisation strong fractionation of heavy rare earth elements (HREEs) over light rare earth elements (LREEs) occurs, along with a pronounced positive europium anomaly. Positive Th/U ratios are commonly observed, although both actinide elements occur in the range of some hundredths of ppb to some ppb. Trace elements were particularly useful in the study of well cycling in two hydraulically interconnected geothermal wells in the town of Murska Sobota, which produce a mixture of low- and high-mineralised waters. 相似文献
6.
Multivariate statistical analysis of geochemical data as indicative of the hydrogeochemical evolution of groundwater in a sedimentary rock aquifer system 总被引:14,自引:0,他引:14
Vincent Cloutier Ren Lefebvre Ren Therrien Martine M. Savard 《Journal of Hydrology》2008,353(3-4):294-313
The study of groundwater hydrogeochemistry of the Paleozoic Basses-Laurentides sedimentary rock aquifer system in Québec produced a large geochemical dataset. Groundwater samples were collected at 153 sites over a 1500 km2 study area and analyzed for major and minor ions. The large number of data can lead to difficulties in the integration, interpretation and representation of the results. Two multivariate statistical methods, hierarchical cluster analysis (HCA) and principal components analysis (PCA), were applied to a subgroup of the dataset to evaluate their usefulness to classify the groundwater samples, and to identify geochemical processes controlling groundwater geochemistry. This subgroup consisted of 144 samples and 14 parameters (Ca2+, Mg2+, Na+, K+, , Cl−, , Fe2+, Mn2+, Br−, Sr2+, F−, Ba2+, HS−). Seven geochemically distinct clusters, C1–C7, resulted from the HCA. Samples from clusters C3, C4, C6 and C7 are mostly located in preferential recharge areas. The majority of these samples have Ca–Mg–HCO3 recharge groundwater (C3, C6, C7) and Na–HCO3 evolved groundwater (C4). Samples from the other three clusters (C1, C2, C5) are characteristic of an aquifer system under confined conditions. The majority of these samples have Na–HCO3 evolved groundwater (C1, C5) and Na–Cl ancient groundwater that exhibits elevated concentrations in Br− (C2). In addition to recognizing the importance of hydrogeological conditions on groundwater geochemistry, the distribution of clusters also showed the importance of the geological formations on minor and trace elements, such as Fe2+, Mn2+, Sr2+, F− and Ba2+. The first five components of the PCA account for 78.3% of the total variance in the dataset. Component 1 is defined by highly positive loadings in Na+, Cl− and Br− and is related to groundwater mixing with Champlain Sea water and solute diffusion from the marine clay aquitard. The high positive loadings in Ca2+ and Mg2+ of component 2 suggest the importance of dissolution of carbonate rocks in this aquifer system. From their characteristic loadings, the first two components are defined as the “salinity” and “hardness” components, respectively. Components 3–5 are related to more local and geological effects. The integration of the HCA and the PCA, with conventional classification of groundwater types, as well as with the hydrogeological and geological contexts, allowed the division of the region into four main geochemical areas, providing an improved regional picture of the aquifer system dynamics and hydrogeochemical evolution of groundwater. The following factors were recognized as influencing the evolution of groundwater identified in every geochemical area: (1) geological characteristics including sedimentary rock type and till mineralogy; (2) hydrogeological characteristics represented by the level of confinement and the hydraulic gradient; and (3) the geological history including the latest glaciation and the Champlain Sea invasion. With its integrated approach, this hydrogeochemical study contributes to the characterization and understanding of complex groundwater flow systems, and provides an example of the long-term geochemical evolution of hydrogeological systems after a major perturbation, in this case seawater invasion. 相似文献
7.
四川盆地西部富钾卤水水文地球化学特征及其成因意义探讨 总被引:6,自引:0,他引:6
四川盆地西部宫钾卤水以深层卤水形式赋存于地下4000余m的中三叠统雷口坡组四段(T2l4)盐系的碳酸盐岩储层中。富钾卤水与海水不同浓缩阶段相比,其中含K+含量异常高,构成液态钾矿资源;Br-、I-、B(3+)、Li+等稀有组分也远超过综合利用工业品位,为优质化工原料水。富钾卤水为沉积变质和钾盐溶滤的复合成因,具有固夜态找钾的指示意义。本文为四川盆地固液态找钾提供了有价值的线索。 相似文献
8.
Ayşen Davraz M. Tahir Nalbantçılar Simge Varol İsmail Önden 《Chemie der Erde / Geochemistry》2022,82(2):125867
A conceptual model with water samples from ten geothermal fields (?smil, Ilg?n (Çavu?cugöl), Tuzlukçu-Ak?ehir, Seydi?ehir and Kavakköy, Hüyük, Ere?li-Akhüyük, Kad?nhan?, Cihanbeyli, Karap?nar and Bey?ehir) in the province of Konya defined the geothermal system. Carbonates, quartzite and marbles of Paleozoic metamorphics are the reservoir rocks and the heating sources are igneous rock intrusions and geothermal gradient. The variable thermal water (CaMgHCO3, CaSO4, NaSO4, CaHCO3, CaNaHCO3, NaCl and CaNaClHCO3) had EC and temperature between 177.8 and 56,100 μS/cm and between 18.3 and 44 °C, respectively. Ca2+ in geothermal fluids are associated with marble and carbonate rocks and the high chloride shows direct connection with deep geothermal system, and prolonged contact with evaporite rocks. Sulphate originates from dissolution of and oxidation of sulphate and sulphur-bearing minerals. The high As, B, F and Mn concentration in some thermal water samples were determined as 85 μg/l, 148.56 mg/l, 3.01 mg/l and 208.13 mg/l, respectively. Reservoir temperatures computed by Na/K geothermometers were between 85.37–158.89 °C for Ak?ehir thermal waters and 58.78–90.45 °C for Ere?li thermal waters. The maximum reservoir temperature of other geothermal waters was 75 °C by the silica geothermometers. 相似文献
9.
A study on the hydrogeology and hydrogeochemistry of groundwater from different depths in a coastal aquifer: Annamalai Nagar,Tamilnadu, India 总被引:3,自引:0,他引:3
S. Chidambaram G. Senthil Kumar M. V. Prasanna A. John Peter AL. Ramanthan K. Srinivasamoorthy 《Environmental Geology》2009,57(1):59-73
Chemical characterization of groundwater is essential to bring out its nature and utility. Samples from shallow and deep ground
water of the same location were collected and studied for their geochemical characteristics following standard procedures
(APHA 1998). Sediment samples from different depths were collected and analysed for minerals using FTIR and SEM. Resisitivity logging
was carried out in the bore well to understand the variations in depth to fresh water potential. The shallow ground water
is dominated by Na–Cl–HCO3–SO4 and deeper groundwater by Na–HCO3–SO4–Cl types. It is observed that there is a significant ionic variation with depth. The ionic strength of the deeper samples
is lesser than in the shallower samples. Wide pH variations in the shallow water samples are due to ion exchange process.
Thermodynamic stability plot was used to identify the state of stability. It is inferred that there is no major significant
difference in the thermodynamic state of stability in the shallow and the deeper aquifers as the aquifer matrix for the shallow
and deeper aquifers are almost similar. Saturation index of Gibbsite, Kaolinite, Calcite, Dolomite and anhydrite, were studied
for shallow and deep aquifers, to identify the difference in hydro chemical signatures. The Si/Al ratios of shallow samples
are less when compared with the deeper samples. Leaching of secondary salts was the chief mechanism controlling the ground
water chemistry of the region. 相似文献
10.
Identification of influencing factors for groundwater quality variation using multivariate analysis 总被引:1,自引:0,他引:1
This paper reports the results of multivariate analysis on the major-ions data present in groundwater collected in a hydrogeochemical
survey of a hard rock terrain in Andhra Pradesh, India. The use of factor analysis is proposed, as a first step, for identifying
the processes influencing the hydrogeochemical variations in groundwater. As a result of the application factor analysis,
three factors were obtained, which explained characterization of groundwater quality and identified the sources for the presence
of ions and its variations in concentrations and their geochemical processes. The natural dissolution of existing rocks of
granites and granitic gneisses is the common influencing source for its hydrogeochemical character in the study area, but
at some localized zones, the human-influenced sources of agricultural, industrial and urbanization are the dominating factors.
The spatial and seasonal variation of the hydrogeochemical processes associated with the factor variables in the groundwater
quality of the study area were analysed and evaluated. 相似文献