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1.
Hydrochemical appraisal of groundwater and its suitability in the intensive agricultural area of Muzaffarnagar district,Uttar Pradesh,India 总被引:1,自引:0,他引:1
Muzaffarnagar is an economically rich district situated in the most fertile plains of two great rivers Ganga and Yamuna in
the Indo-gangetic plains, with agricultural land irrigated by both surface water as well as groundwater. An investigation
has been carried out to understand the hydrochemistry of the groundwater and its suitability for irrigation uses. Groundwater
in the study area is neutral to moderately alkaline in nature. Chemistry of groundwater suggests that alkaline earths (Ca + Mg)
significantly exceed the alkalis (Na + K) and weak acids exceed the strong acids (Cl + SO4), suggesting the dominance of carbonate weathering followed by silicate weathering. Majority of the groundwater samples (62%)
posses Ca–Mg–HCO3 type of hydrochemical species, followed by Ca–Na–Mg–HCO3, Na–Ca–Mg–HCO3, Ca–Mg–Na–HCO3–Cl and Na–Ca–HCO3–SO4 types. A positive high correlation (r
2 = 0.928) between Na and Cl suggests that the salinity of groundwater is due to intermixing of two or more groundwater bodies
with different hydrochemical compositions. Barring a few locations, most of the groundwater samples are suitable for irrigation
uses. Chemical fertilizers, sugar factories and anthropogenic activities are contributing to the sulphate and chloride concentrations
in the groundwater of the study area. Overexploitation of aquifers induced multi componential mixing of groundwater with agricultural
return flow waters is responsible for generating groundwater of various compositions in its lateral extent. 相似文献
2.
Hydrochemical evolution and water quality along the groundwater flow path in the Sandıklı plain, Afyon, Turkey 总被引:1,自引:0,他引:1
M. Afşin 《Environmental Geology》1997,31(3-4):221-230
An unconfined aquifer system suggests an open system in the study area. Hydrochemical evolution is related to the flow path
of groundwater. The groundwaters are divided into two hydrochemical facies in the study area, 1) Ca–Mg–HCO3 and 2) Ca–Mg–SO4HCO3. Facies 1 has shallow (young) waters which dominate in recharge areas during rapid flow conditions, whereas facies 2 may
show shallow and mixed waters which dominate intermediate or discharge areas during low flow conditions. Ionic concentrations,
TDS, EC and water quality are related to groundwater residence time and groundwater types. The groundwaters in the plain are
chemically potable and suitable for both domestic and agricultural purposes.
Received: 20 May 1996 · Accepted: 30 July 1996 相似文献
3.
Evaluation of hydrogeochemical processes in arsenic-contaminated alluvial aquifers in parts of Mid-Ganga Basin,Bihar, Eastern India 总被引:1,自引:1,他引:0
Dipankar Saha Sreehari S. Sarangam Shailendra N. Dwivedi Kuldeep G. Bhartariya 《Environmental Earth Sciences》2010,61(4):799-811
The study region covers 1,650 km2 of the Mid-Ganga Basin in Bihar, experiencing intensive groundwater draft. The area forms a part of the Gangetic alluvial
plain where high incidence of arsenic groundwater contamination (>50 μg/l) has recently been detected. Seventy-seven groundwater
samples have been collected and analysed for major ions, iron and arsenic. Arsenic contamination (max 620 μg/l) is confined
in hand pump zones (15–35 m) within the newer alluvium deposited during Middle Holocene to Recent age. The older alluvial
aquifers are arsenic-safe and recorded maximum concentration as 9 μg/l. Out of 12 hydrochemical facies identified, four have
been found arsenic-affected: Ca–HCO3, Mg–HCO3, Ca–Mg–HCO3 and Mg–Ca–HCO3. The geochemical evolution of groundwater, as investigated by graphical interpretation and statistical techniques (correlation,
principal component analysis) revealed that dissolution of detrital calcite, dolomite and infiltration of rainwater are the
major processes shaping the groundwater chemistry in the newer alluvium. Arsenic and iron showed strong positive correlation.
Rainfall infiltration, carrying organic matter from recently accumulated biomass from this flood-prone belt, plays a critical
role in releasing arsenic and iron present in the sediments. Geochemical evolution of groundwater in older alluvium follows
a different path, where cation-exchange has been identified as a significant process. 相似文献
4.
Erik Espinosa María Aurora Armienta Olivia Cruz Alejandra Aguayo Nora Ceniceros 《Environmental Geology》2009,58(7):1467-1477
High arsenic (As) groundwater is widely distributed in northwestern Hetao Plain, an arid region with sluggish groundwater
flow. Observed As concentration in groundwater from wells ranges from 76 to 1,093 μg/l. Most water samples have high total
dissolved solids, with Cl and HCO3 as the dominant anions and Na as the dominant cation. The major hydrochemical types of most saline groundwaters are Na–Mg–Cl–HCO3 and Na–Mg–Cl. By contrast, fresh groundwaters generally belong to the Na–Mg–HCO3 type. High concentrations of arsenic in shallow aquifers are associated with strongly reducing conditions, as evidenced by
high concentrations of dissolved organic carbon, ammonium, as well as dissolved sulfide and Fe, dominance of arsenite, relatively
low concentrations of nitrate and sulfate, and occasionally high content of dissolved methane (CH4). High As groundwaters from different places at Hetao Plain experienced different redox processes. Fluoride is also present
in high As groundwater, ranging between 0.40 and 3.36 mg/l. Although fluorosis poses an additional health problem in the region,
it does not correlate well with As in spatial distribution. Geochemical analysis indicates that evapotranspiration is an important
process controlling the enrichment of Na and Cl, as well as trace elements such as As, B, and Br in groundwater.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
5.
The degradation of groundwater quality, which has been noted in the recent years, is closely connected to the intensification
of agriculture, the unreasonable use of chemical fertilizers and the excess consumption of large volumes of irrigation water.
In the hilly region of central Thessaly in Greece, which suffers the consequences of intense agricultural use, a hydrogeological
study is carried out, taking groundwater samples from springs and boreholes in the Neogene aquifers. The aim of this study
is the investigation of irrigation management, water quality and suitability for various uses (water supply, irrigation),
the degradation degree and the spatial distribution of pollutants using GIS. The following hydrochemical types prevail in
the groundwater of the study area: Ca–Mg–HCO3, Mg–Ca–Na–HCO3 and Na–HCO3. In the above shallow aquifers, especially high values of NO3
− (31.7–299.0), NH4
+ (0.12–1.11), NO2
− (0.018–0.109), PO4
3− (0.07–0.55), SO4
2− (47.5–146.5) and Cl− (24.8–146.5) are found, particularly near inhabited areas (values are in mg L−1). The water of shallow aquifers is considered unsuitable for human use due to their high polluting load, while the water
of the deeper aquifers is suitable for human consumption. Regarding water suitability for irrigation, the evaluation of SAR
(0.153–7.397) and EC (481–1,680 μS cm−1) resulted in classification category ‘C3S1’, indicating high salinity and low sodium water which can be used for irrigation
in most soils and crops with little to medium danger of development of exchangeable sodium and salinity. The statistical data
analysis, the factor analysis and the GIS application have brought out the vulnerable-problematic zones in chemical compounds
of nitrogen and phosphates. The groundwater quality degradation is localized and related exclusively to human activities.
Based on 2005 and 2008 estimates, the annual safe yield of the region’s aquifers were nearly 41.95 MCM. However, the existing
situation is that 6.37 MCM of water is over extracted from these aquifers. 相似文献
6.
The total amount of groundwater resources in the middle and upper Odra River basin is 5200×103 m3/d, or about 7.7% of the disposable groundwater resources of Poland. The average modulus of groundwater resources is about
1.4 L/s/km2. Of the 180 'Major Groundwater Basins' (MGWB) in Poland, 43 are partly or totally located within the study area. The MGWB
in southwestern Poland have an average modulus of groundwater resources about 2.28 L/s/km2 and thus have abundant water resources in comparison to MGWB from other parts of the country.
Several types of mineral waters occur in the middle and upper Odra River basin. These waters are concentrated especially in
the Sudety Mountains. Carbon-dioxide waters, with yields of 414 m3/h, are the most widespread of Sudetic mineral waters.
The fresh waters of the crystalline basement have a low mineralization, commonly less than 100 mg/L; they are a HCO3–Ca–Mg or SO4–Ca–Mg type of water. Various hydrochemical compositions characterize the groundwater in sedimentary rocks. The shallow aquifers
are under risk of atmospheric pollution and anthropogenic effects. To prevent the degradation of groundwater resources in
the middle and upper Odra River basin, Critical Protection Areas have been designated within the MGWB.
Received, January 1995 Revised, May 1996, August 1997 Accepted, August 1997 相似文献
7.
Recharge source and hydrogeochemical evolution of shallow groundwater in a complex alluvial fan system,southwest of North China Plain 总被引:4,自引:0,他引:4
Fadong Li Guoying Pan Changyuan Tang Qiuying Zhang Jingjie Yu 《Environmental Geology》2008,55(5):1109-1122
Many cities around the world are developed at alluvial fans. With economic and industrial development and increase in population,
quality and quantity of groundwater are often damaged by over-exploitation in these areas. In order to realistically assess
these groundwater resources and their sustainability, it is vital to understand the recharge sources and hydrogeochemical
evolution of groundwater in alluvial fans. In March 2006, groundwater and surface water were sampled for major element analysis
and stable isotope (oxygen-18 and deuterium) compositions in Xinxiang, which is located at a complex alluvial fan system composed
of a mountainous area, Taihang Mt. alluvial fan and Yellow River alluvial fan. In the Taihang mountainous area, the groundwater
was recharged by precipitation and was characterized by Ca–HCO3 type water with depleted δ18O and δD (mean value of −8.8‰ δ18O). Along the flow path from the mountainous area to Taihang Mt. alluvial fan, the groundwater became geochemically complex
(Ca–Na–Mg–HCO3–Cl–SO4 type), and heavier δ18O and δD were observed (around −8‰ δ18O). Before the surface water with mean δ18O of −8.7‰ recharged to groundwater, it underwent isotopic enrichment in Taihang Mt. alluvial fan. Chemical mixture and ion
exchange are expected to be responsible for the chemical evolution of groundwater in Yellow River alluvial fan. Transferred
water from the Yellow River is the main source of the groundwater in the Yellow River alluvial fan in the south of the study
area, and stable isotopic compositions of the groundwater (mean value of −8.8‰ δ18O) were similar to those of transferred water (−8.9‰), increasing from the southern boundary of the study area to the distal
end of the fan. The groundwater underwent chemical evolution from Ca–HCO3, Na–HCO3, to Na–SO4. A conceptual model, integrating stiff diagrams, is used to describe the spatial variation of recharge sources, chemical
evolution, and groundwater flow paths in the complex alluvial fan aquifer system. 相似文献
8.
The sea level rise has its own-bearing on the coastal recession and hydro-environmental degradation of the River Nile Delta.
Attempts are made here to use remote sensing to detect the coastal recession in some selected parts and delineating the chemistry
of groundwater aquifers and surface water, which lie along south-mid-northern and coastal zone of the Nile Delta. Eight water
samples from groundwater monitoring wells and 13 water samples from surface water were collected and analyzed for various
hydrochemical parameters. The groundwater samples are classified into five hydrochemical facies on Hill-Piper trilinear diagram
based on the dominance of different cations and anions: facies 1: Ca–Mg–Na–HCO3–Cl–SO4 type I; facies 2: Na–Cl–HCO3 type II; facies 3: Na–Ca–Mg–Cl type III, facies 4: Ca–Na–Mg–Cl–HCO3 type IV and facies 5: Na–Mg–Cl type V. The hydrochemical facies showed that the majority of samples were enriched in sodium,
bicarbonate and chloride types and, which reflected that the sea water and tidal channel play a major role in controlling
the groundwater chemical composition in the Quaternary shallow aquifers, with a severe degradation going north of Nile Delta.
Also, the relationship between the dissolved chloride (Cl, mmol/l), as a variable, and other major ion combinations (in mmol/l)
were considered as another criterion for chemical classification system. The low and medium chloride groundwater occurs in
southern and mid Nile Delta (Classes A and B), whereas the high and very high chloride (classes D and C) almost covers the
northern parts of the Nile Delta indicating the severe effect of sea water intrusion. Other facets of hydro-environmental
degradation are reflected through monitoring the soil degradation process within the last two decades in the northern part
of Nile Delta. Land degradation was assessed by adopting new approach through the integration of GLASOD/FAO approach and Remote
Sensing/GIS techniques. The main types of human induced soil degradation observed in the studied area are salinity, alkalinity
(sodicity), compaction and water logging. On the other hand, water erosion because of sea rise is assessed. Multi-dates satellite
data from Landsat TM and ETM+ images dated 1983 and 2003 were used to detect the changes of shoreline during the last two
decades. The obtained results showed that, the eroded areas were determined as 568.20 acre; meanwhile the accreted areas were
detected as 494.61 acre during the 20-year period. 相似文献
9.
Chemical characteristics of groundwater in parts of mountainous region, Alvand, Hamadan, Iran 总被引:5,自引:0,他引:5
Mohsen Jalali 《Environmental Geology》2006,51(3):433-446
Eighty-seven groundwater samples have been collected from a mountainous region (Alvand, Iran) for hydrochemical investigations to understand the sources of dissolved ions and assess the chemical quality of the groundwater. Most water quality parameters are within World Health Organization acceptable limits set for drinking water. The least mineralized water is found closest to the main recharge zones and the salinity of water increased towards the north of the basin. The most prevalent water type is Ca–HCO3 followed by water types Ca–NO3, Ca–Cl, Ca–SO4 and Mg–HCO3. The Ca–NO3 water type is associated with high nitrate pollution. Agricultural and industrial activities were associated with elevated level of NO3−. Mineral dissolution/weathering of evaporites dominates the major element hydrochemistry of the area. Chemical properties of groundwater in Alvand region are controlled both by natural geochemical processes and anthropogenic activities. 相似文献
10.
Galip Yuce 《Environmental Geology》2007,51(5):857-868
The aim of this study was to determine geochemical properties of groundwater and thermal water in the Misli Basin and to assess
thermal water intrusion into shallow groundwater due to over-extraction. According to isotope and hydrochemical analyses results,
sampled waters can be divided into three groups: cold, thermal, and mixed waters. Only a few waters reach water–rock chemical
equilibrium. Thermal waters in the area are characterized by Na+–Cl−–HCO3−, while the cold waters by CaHCO3 facies. On the basis of isotope results, thermal waters in the Misli basin are meteoric origin. In particular, δ18O and δ2H values of shallow groundwater vary from −10.2 to −12.2‰ and −71.2 to −82‰, while those of thermal waters range from −7.8
to −10.1‰ and from −67 to −74‰, respectively. The tritium values of shallow groundwater having short circulation as young
waters coming from wells that range from 30 to 70 m in depth vary from 10 to 14 TU. The average tritium activity of groundwater
in depths more than 100 m is 1.59 ± 1.16, which indicates long circulation. The rapid infiltration of the precipitation, the
recycling of the evaporated irrigation water, the influence of thermal fluids and the heterogeneity of the aquifer make it
difficult to determine groundwater quality changes in the Misli Basin. Obtained results show that further lowering of the
groundwater table by over-consumption will cause further intrusion of thermal water which resulted in high mineral content
into the fresh groundwater aquifer. Because of this phenomenon, the concentrations of some chemical components which impairs
water quality in terms of irrigation purposes in shallow groundwaters, such as Na+, B, and Cl−, are highy probably expected to increase in time. 相似文献
11.
Hydrogeological and mixing process of waters in aquifers in arid regions: a case study in San Luis Potosi Valley,Mexico 总被引:1,自引:0,他引:1
J. A. Ramos-Leal V. J. Martínez-Ruiz J. R. Rangel-Mendez M. C. Alfaro de la Torre 《Environmental Geology》2007,53(2):325-337
The climatic conditions of arid regions are characterized by high temperatures, low precipitation and high evapotranspiration
rates that can explain the reduced recharge of aquifers. Thus, in these regions, there are some problems related to the groundwater
quality and recharge that makes worse the problem of groundwater supply. A model, taking into account ternary mixtures, is
presented and applied to a case study: the aquifer of San Luis Potosi valley located in the highlands of the central part
of Mexico. In this valley, four hydrochemical facies were identified that correspond to the Ca–Na + K–HCO3, Na + K–Ca–HCO3, Ca–HCO3 and Ca–SO4 types. From this characterization, it was found out that the recharge area (known as Bledos Graben) is located at the SE
of the valley; the deep water flow comes from there (Villa de Reyes and Alvarez Range) to the center of the valley. Mixture
fractions were obtained by using chlorides and fluorides as conservative elements, from which it was possible to quantify
the contribution of each member to the groundwater quality. According to these results, the contributions to the water extracted
from this aquifer are as follows: shallow flows 50%, deep flows from Villa de Reyes 27%, and flows coming from the Alvarez
Ranges about 15%. 相似文献
12.
Lingfen Wang Fusheng Hu Lihe Yin Li Wan Qiusheng Yu 《Environmental Earth Sciences》2013,69(6):2037-2057
The Yinchuan plain is located in the arid climate zone of NW China. The western margin of the plain is the Helan mountain connecting a series of normal slip faults. The eastern margin of the plain connects with the Yellow River and adjacents with the Ordos platform. The south of the plain is bordered by the EN fault of the Niushou mountain. The bottom of the plain is the Carboniferous, Permian, or Ordovician rocks. Based on the analysis of groundwater hydrochemical and isotopic indicators, this study aims to identify the groundwater recharge and discharge in the Yinchuan plain, China. The hydrochemical types of the groundwater are HCO3–SO4 in the west, HCO3–Cl in the middle, and Cl–SO4 in the east. The hydrochemical types are HCO3–SO4 in the south, HCO3–Cl and SO4–HCO3 in the middle. The hydrochemical types are complex in the north, mainly SO4–HCO3 and Cl–SO4. Deuterium, 18O, and tritium values of groundwater indicate that groundwater recharge sources include precipitation, bedrock fissure water, and irrigation return water. Groundwater discharges include evaporation, abstraction, and discharge to surface water. According to the EW isotopic profile, the groundwater flow system (GFS) in the Yinchuan plain can be divided into local flow systems (LFS) and regional flow systems (RFS). Groundwater has lower TDS and higher tritium in the southern Yellow River alluvial plain and groundwater age ranges from 6 to 25 years. The range of groundwater renewal rates is from 11 to 15 % a?1. The depth of the water cycle is small, and groundwater circulates fast and has high renewal rates. Groundwater has higher TDS and lower tritium in the northern Yellow River alluvial plain. The range of groundwater age is from 45 to 57 years, and renewal rate is from 6 to 0.1 % a?1. The depth of the water cycle is larger. Groundwater circulates slowly and has low renewal rates. 相似文献
13.
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
14.
Kaveh Pazand Ardeshir Hezarkhani Yousef Ghanbari Nasrin Aghavali 《Environmental Earth Sciences》2012,65(3):871-879
The chemical analysis of 59 water wells in Meshkinshar area, Ardabil province NW of IRAN has been evaluated to determine the
hydrogeochemical processes and ion concentration background in the region. The dominated hydrochemical types are Na–SO4, Ca–HCO3, Na–HCO3 and Na–Cl in the whole area. Based on the total hardness, the groundwater is soft. According to electrical conductivity and
sodium adsorption ratio, the most dominant classes are C1–S1, C2–S1 and C3–S1. The major ion concentrations are below the
acceptable level for drinking water. The groundwater salinity hazard is medium to high but the Na hazard is low to medium
and in regard of irrigation water the quality is low to medium. So the drainage system is necessary to avoid the increase
of toxic salt concentrations. 相似文献
15.
Wilson Yetoh Fantong Hiroshi Satake Festus T. Aka Samuel N. Ayonghe Kazuyoshi Asai Ajit K. Mandal Andrew A. Ako 《Environmental Earth Sciences》2010,60(1):107-120
Unplanned exploitation of groundwater constitutes emerging water-related threats to MayoTsanaga River Basin. Shallow groundwater
from crystalline and detrital sediment aquifers, together with rain, dams, springs, and rivers were chemically and isotopically
investigated to appraise its evolution, recharge source and mechanisms, flow direction, and age which were used to evaluate
the groundwater susceptibility to contamination and the basin’s stage of salinization. The groundwater which is Ca–Na–HCO3 type is a chemically evolved equivalent of surface waters and rain water with Ca–Mg–Cl–SO4 chemistry. The monsoon rain recharged the groundwater preferentially at an average rate of 74 mm/year, while surface waters
recharge upon evaporation. Altitude effect of rain and springs show a similar variation of −0.4‰ for δ18O/100 m, but the springs which were recharged at 452, 679, and 773 m asl show enrichment of δ18O through evaporation by 0.8‰ corresponding to 3% of water loss during recharge. The groundwater which shows both local and
regional flow regimes gets older towards the basins` margin with coeval enrichment in F− and depletion in NO3
−. Incidentally, younger groundwaters are susceptible to anthropogenic contamination and older groundwaters are sinks of lithologenic
fluoride. The basins salinization is still at an early stage. 相似文献
16.
The Markanda river basin occupying an area of about 1547 km2 is a part of the alluvial deposits of the Indo- Gangetic plain near the Himalayan foothills in the northwest India. The region
is associated with active agricultural activities and makes significant contribution to the country’s agricultural products.
Assessment of groundwater quality for irrigation use and hydrochemical evolution of groundwater has been studied. Hydrochemical
analysis has been carried out based on concentrations of Ca2+, Mg2+, Na+, K+, Cl−, SO4
2−, CO3
2− and HCO3
−. Sodium adsorption ratio (SAR), percent sodium (%Na), permeability index (PI) and Trilinear diagram have been studied to
evaluate suitability of irrigation use. Hydrochemical evolution has been analyzed based on the Chebotarev sequence and expanded
Durov diagram. SAR, %Na and PI results indicate that the groundwater in the basin is suitable for irrigation use. Analysis
on Trilinear diagram reveals that hydrochemical facies are dominated by HCO3
−- Ca2+- Mg2+ facies indicating that the groundwater is associated with recharge waters percolating through sandstone and limestone rocks
which are exposed in the northern part of the basin. Studies based on Chebotarev anion sequence and expanded Durov diagram
indicate that the evolution of groundwater belongs to initial to intermediate stage indicating fresh water quality. Thus,
the present work reveals that groundwater in the Markanda basin is of good quality and is suitable for all uses including
interbasin water transfer in the region. 相似文献
17.
《Applied Geochemistry》2002,17(8):1047-1060
Due to the scarcity of water resources in semiarid sedimentary basins, hill reservoirs are often constructed to recharge groundwater and limit runoff induced water loss. The impact of such reservoirs on groundwater chemistry is investigated in the aquifers of the El Gouazine watershed, Central Tunisia. Three groundwater types are recognised, Ca–HCO3, Na–Cl and Ca–SO4. The strong similarity between host rock and groundwater chemistries indicates significant rock–water interaction. A flowpath, along which the chemical composition of the groundwater evolves, can be identified using the contrast in stable isotope signature between upstream and downstream groundwater. Shallow upstream groundwater is recharged by the infiltration of rainwater with the rate of recharge strongly linked to the permeability of the host lithology. Calcium and HCO3 are supplied to an alluvial aquifer from a more rapidly recharged limestone aquifer with the concentration of Ca and HCO3 ions decreasing by dilution. The alluvial aquifer is also enriched in Ca and SO4 during the downstream flow of groundwater through gypsiferous materials. There is evidence of mixing between meteoric groundwater and evaporated reservoir water. Below the reservoir and partly responsible for reservoir leakage is a sandy aquifer, formed by weathering and erosion of a sandstone host which also supplies water to the alluvial aquifer. 相似文献
18.
Geochemical evolution of groundwater in carbonate aquifers in Taiyuan, northern China 总被引:4,自引:0,他引:4
Rui Ma Yanxin WangZiyong Sun Chunmiao ZhengTeng Ma Henning Prommer 《Applied Geochemistry》2011,26(5):884-897
Thirty-nine samples of both cold and thermal karst groundwater from Taiyuan, northern China were collected and analyzed with the aim of developing a better understanding of the geochemical processes that control the groundwater quality evolution in the region’s carbonate aquifers. The region’s karst groundwater system was divided into three geologically distinct sub-systems, namely, the Xishan Mountain karst groundwater subsystem (XMK), the Dongshan Mountain karst groundwater subsystem (DMK) and the Beishan Mountain karst groundwater subsystem (BMK). Hydrochemical properties of the karst groundwaters evolve from the recharge zones towards the cold water discharge zones and further towards the thermal water discharge zones. In the XMK and the DMK, the hydrochemical type of the groundwater evolves from HCO3-Ca·Mg in the recharge - flow-through zone, to HCO3·SO4-Ca·Mg/SO4·HCO3-Ca·Mg in the cold water discharge zone, and further to SO4-Ca·Mg in the thermal water discharge zone. By contrast, the water type changes from HCO3-Ca·Mg to HCO3·SO4-Ca·Mg in the BMK, with almost invariable TDS and temperatures all along from the recharge to the discharge zone. The concentrations of Sr, Si, Fe, F− and of some trace elements (Al, B, Li, Mn, Mo, Co, Ni) increase as groundwater temperature increases. Different hydrogeochemical processes occur in the three karst groundwater sub-systems. In the XMK and the DMK, the geochemical evolution of the groundwater is jointly controlled by carbonate dissolution/precipitation, gypsum dissolution and dedolomitization, while only calcite and dolomite dissolution/precipitation occurs in the BMK without dedolomitization. The hydrogeochemical data of the karst groundwaters were used to construct individual geochemical reaction models for each of the three different karst groundwater sub-systems. The modeling results confirm that dedolomization is the major process controlling hydrochemical changes in the XMK and the DMK. In the thermal groundwaters, the dissolution rates of fluorite, siderite and strontianite were found to exceed those of the cold karst groundwater systems, which can explain the higher concentrations of F−, Fe and Sr2+ that are found in these waters. 相似文献
19.
Groundwater in alluvial aquifers of the Wakatipu and Wanaka basins, Central Otago, New Zealand, has a composition expressed
in equivalent units of Ca2+≫Mg2+≅Na+>K+ for cations, and HCO3
–≫SO4
2->NO3
–≅Cl– for anions. Ca2+ and HCO3
– occur on a 1 : 1 equivalent basis and account for >80% of the ions in solution. However, some groundwater has increased proportions
of Na+ and SO4
2-, reflecting a different source for this water.
The rock material of the alluvial aquifers of both basins is derived from the erosion and weathering of metamorphic Otago
Schist (grey and green schists). Calcite is an accessory mineral in both the grey and green schists at <5% of the rock. Geological
mapping of both basins indicates that dissolution of calcite from the schist is the only likely mechanism for producing groundwater
with such a constant composition dominated by Ca2+ and HCO3
– on a 1 : 1 equivalent basis. Groundwater with higher proportions of Na+ and SO4
2- occurs near areas where the schist crops out at the surface, and this groundwater represents deeper and possibly older water
derived from basement fluids. Anomalously high K+ in the Wakatipu basin and high NO3
– concentrations in the Wanaka basin cannot be accounted for by interaction with basement lithologies, and these concentrations
probably represent the influence of anthropogenic sources on groundwater composition.
Received, June 1996 Revised, March 1997, July 1997 Accepted, July 1997 相似文献
20.
Large karstic springs in east-central Florida, USA were studied using multi-tracer and geochemical modeling techniques to better understand groundwater flow paths and mixing of shallow and deep groundwater. Spring water types included Ca–HCO3 (six), Na–Cl (four), and mixed (one). The evolution of water chemistry for Ca–HCO3 spring waters was modeled by reactions of rainwater with soil organic matter, calcite, and dolomite under oxic conditions. The Na–Cl and mixed-type springs were modeled by reactions of either rainwater or Upper Floridan aquifer water with soil organic matter, calcite, and dolomite under oxic conditions and mixed with varying proportions of saline Lower Floridan aquifer water, which represented 4–53% of the total spring discharge. Multiple-tracer data—chlorofluorocarbon CFC-113, tritium (3H), helium-3 (3Hetrit), sulfur hexafluoride (SF6)—for four Ca–HCO3 spring waters were consistent with binary mixing curves representing water recharged during 1980 or 1990 mixing with an older (recharged before 1940) tracer-free component. Young-water mixing fractions ranged from 0.3 to 0.7. Tracer concentration data for two Na–Cl spring waters appear to be consistent with binary mixtures of 1990 water with older water recharged in 1965 or 1975. Nitrate-N concentrations are inversely related to apparent ages of spring waters, which indicated that elevated nitrate-N concentrations were likely contributed from recent recharge.The online version of the original article can be found at 相似文献