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1.
《Applied Geochemistry》2005,20(4):789-805
Mineralogical, hydrochemical and S isotope data were used to constrain hydrogeochemical processes that produce acid mine drainage from sulfidic waste at the historic Mount Morgan Au–Cu mine, and the factors controlling the concentration of SO4 and environmentally hazardous metals in the nearby Dee River in Queensland, Australia. Some highly contaminated acid waters, with metal contents up to hundreds of orders of magnitude greater than the Australia–New Zealand environmental standards, by-pass the water management system at the site and drain into the adjacent Dee River.Mine drainage precipitates at Mt. Morgan were classified into 4 major groups and were identified as hydrous sulfates and hydroxides of Fe and Al with various contents of other metals. These minerals contain adsorbed or mineralogically bound metals that are released into the water system after rainfall events. Sulfate in open pit water and collection sumps generally has a narrow range of S isotope compositions (δ34S = 1.8–3.7‰) that is comparable to the orebody sulfides and makes S isotopes useful for tracing SO4 back to its source. The higher δ34S values for No. 2 Mill Diesel sump may be attributed to a difference in the source. Dissolved SO4 in the river above the mine influence and 20 km downstream show distinctive heavier isotope compositions (δ34S = 5.4–6.8‰). The Dee River downstream of the mine is enriched in 34S (δ34S = 2.8–5.4‰) compared with mine drainage possibly as a result of bacterial SO4 reduction in the weir pools, and in the water bodies within the river channel. The SO4 and metals attenuate downstream by a combination of dilution with the receiving waters, SO4 reduction, and the precipitation of Fe and Al sulfates and hydroxides. It is suggested here that in subtropical Queensland, with distinct wet and dry seasons, temporary reducing environments in the river play an important role in S isotope systematics. 相似文献
2.
Agustín Gómez-Alvarez Diana Meza-Figueroa Arturo I. Villalba-Atondo Jesús Leobardo Valenzuela-García Jorge Ramírez-Hernández Javier Almendariz-Tapia 《Environmental Geology》2009,57(7):1469-1479
The San Pedro River (SPR) is located in northern Sonora (Mexico) and southeastern Arizona (USA). SPR is a transboundary river
that develops along the Sonora (Mexico) and Arizona (USA) border, and is considered the main source of water for a variety
of users (human settlements, agriculture, livestock, and industry). The SPR originates in the historic Cananea mining area,
which hosts some of the most important copper mineralizations in Mexico. Acid mine drainage derived from mine tailings is
currently reaching a tributary of the SPR near Cananea City, resulting in the contamination of the SPR with heavy metals and
sulfates in water and sediments. This study documents the accumulation and distribution of heavy metals in surface water along
a segment of the SPR from 1993 to 2005. Total concentrations of Cd, Cu, Fe, Mn, Pb, and Zn in surface waters are above maximum
permissible levels in sampling sites near mine tailing deposits. Nevertheless, a significant decrease in the Fe and SO4
2− in surface water (SO4
2−: 7,180–460.39 mg/L; Fe: 1,600–9.51 mg/L) as well as a gradual decrease in the heavy and transition metal content were observed
during the period from 1994 to 2005. Approximately 2.3 km downstream of the mine tailings, the heavy metal content of the
water drops quickly following an increase in pH values due to the discharging of wastewater into the river. The attenuation
of the heavy metal content in surface waters is related to stream sediment precipitation (accompanied by metal coprecipitation
and sorption) and water dilution. Determining the heavy metal concentration led to the conclusion that the Cananea mining
area and the San Pedro River are ecosystems that are impacted by the mining industry and by untreated wastewater discharges
arising from the city of Cananea (Sonora, Mexico). 相似文献
3.
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
4.
D. Ciszewski 《Environmental Geology》1997,29(1-2):50-57
The influence of sources of effluents on pollution of bottom sediments of the small Chechło River (23 km long, mean discharge
1.5 m3 s–1) in southern Poland was examined through analysis of heavy metals distribution in transverse and longitudinal cross sections.
Underground waters from a Pb–Zn mine cause very high concentrations of Zn, Cd, and Pb in both fractions investigated (<1 mm
and <0.063 mm) of sediments in the active channel zone, whereas sedimentation of huge amounts of suspended matter discharged
from oil refinery cause concentrations of heavy metals in fine fractions rather uniform in cross sections. In the lowest reach,
with relatively reduced contamination, the highest concentration both in fine and coarse fractions occurs close to the river
banks and in the deepest points of the channel. The lowest concentrations have been found at the points of strongest reworking
and accumulation of sandy material in the riverbed.
Received: 25 April 1995 · Accepted: 11 September 1995 相似文献
5.
Andrea I. Pasquini Stella M. Formica Gabriela A. Sacchi 《Environmental Earth Sciences》2012,65(2):453-467
Suquía River is a medium-sized hydrological system (basin area of ~7,700 km2) that supplies fresh water to Córdoba city, a town of ~1,500,000 inhabitants in central Argentina. This paper examines the
present-day hydrochemistry of Suquía River urban catchment analyzing its major and minor dissolved components, and the nutrients
variability by means of QUAL-2K modeling software. The Suquía River has bicarbonate-type waters upstream the city and sulfate-type
waters right downstream, whereas they exhibit a mixed-to-alkali-type cationic composition. The seasonal analysis of its major
dissolved constituents clearly showed a dilution process during the wet season (i.e. austral summer). In the last 20 years,
the Suquía River has modified its anionic composition, now showing higher relative concentrations of SO4
2− as a consequence of urban activities. However, trace elements dissolved concentrations do not evidence a strong pollution
effect. Nutrients [nitrogen species, total phosphorous (TP)] and related parameters, such as biochemical oxygen demand (BOD),
and dissolved oxygen (DO), evidence a clear influence of human activities. The QUAL-2K model was used to evaluate the spatial
behavior of selected nutrients and associated variables, (i.e. TP, N–NH4
+, N–NO3
−, DO, BOD). Nutrient concentrations are affected by point sources of contaminants, particularly domestic waste and sewage,
as well as by diffuse agricultural pollution. A calibrated QUAL-2K modeling exercise clearly shows the impact of the Córdoba
city’s municipal wastewater treatment plant on the Suquía River water quality. 相似文献
6.
The Sanggok mine used to be one of the largest lead-zinc mines in the Hwanggangri mining district, Republic of Korea. The
present study characterizes the heavy metal contamination in the abandoned Sanggok mine creek on the basis of physico-chemical
properties of various kinds of water samples (mine, surface and groundwater). Hydrochemistry of the water samples is characterized
by the relatively significant enrichment of Ca2+, HCO3
–, NO3
– and Cl– in the surface and groundwaters, whereas the mine water is relatively enriched in Ca2+, Mg2+, heavy metals, and HCO3
– and SO4
2–. The more polluted mine water has a lower pH and higher Eh, conductivity and TDS values. The concentrations of some toxic
elements (Al, As, Cd, Cu, Fe, Mn, Pb, Se, Sr, Pb and Zn) are tens to hundreds of times higher in the mine water than in the
unpolluted surface and groundwaters. However, most immobile toxic pollutants from the mine drainage were quickly removed from
the surface water by the precipitation of Al and Fe oxyhydroxides. Geochemical modeling showed that potentially toxic heavy
metals might exist largely in the forms of MSO4
2– and M2+ in the mine water. These metals in the surface and groundwaters could form M2+, CO3
2– and OH– complex ions. Computer simulation indicates that the saturation indices of albite, alunite, anhydrite, chlorite, fluorite,
gypsum, halloysite and strontianite in the water samples are undersaturated and have progressively evolved toward the saturation
condition. However, barite, calcite, chalcedony, dolomite, gibbsite, illite and quartz were in equilibrium, and only clay
minerals were supersaturated. Ground and mine waters seemed to be in equilibrium with kaolinite field, but some surface water
were in equilibrium with gibbsite and seceded from the stability field of quartz. This indicates that surface water samples
in reaction with carbonate rocks would first equilibrate with carbonate minerals, then gibbsite to kaolinite. Investigations
on water quality and environmental improvement of the severely polluted Sanggok creek, as well as remediation methods on the
possible future pollution of the groundwater by the acid mine drainage from the abandoned metal mines, are urgently required.
Received: 4 February 2000 · Accepted: 9 May 2000 相似文献
7.
Xueyan Jiang Zhigang Yu Teh-Lung Ku Xinglun Kang Wei Wei Hongtao Chen 《Estuaries and Coasts》2007,30(6):919-926
The Yellow River (Huanghe) is the second largest river in China and is known for its high turbidity. It also has remarkably
high levels of dissolved uranium (U) concentrations (up to 38 nmol 1-1). To examine the mixing behavior of dissolved U between river water and seawater, surface water samples were collected along
a salinity gradient from the Yellow River plume during September 2004 and were measured for dissolved U concentration,234U:238U activity ratio, phosphate (PO4
3–), and suspended particulate matter. Laboratory experiments were also conducted to simulate the mixing process in the Yellow
River plume using unfiltered Yellow River water and filtered seawater. The results showed a nonconservative behavior for dissolved
U at salinities < 20 with an addition of U to the plume waters estimated at about 1.4 X 105 mol yr–1. A similarity between variations in dissolved U and PO4
3– with salinity was also found. There are two major mechanisms, desorption from suspended sediments and diffusion from interstitial
waters of bottom sediments, that may cause the elevated concentrations of dissolved U and PO4
3– in mid-salinity waters. Mixing experiments indicate that desorption seems more responsible for the elevated dissolved U concentrations,
whereas diffusion influences more the enrichment of PO4
3–. 相似文献
8.
Effect of acid mine drainage on a karst basin: a case study on the high-As coal mining area in Guizhou province,China 总被引:2,自引:2,他引:0
Xiuzhen Tao Pan Wu Changyuan Tang Hong Liu Jing Sun 《Environmental Earth Sciences》2012,65(3):631-638
Acid mine drainage (AMD) is a common pollution in mining areas due to the oxidation of pyrite and associated sulfide minerals
at mines, tailings and mine dumps. Elevated metals (Fe, Mn, Al) and metalloids (As, Hg) in AMD would deteriorate the local aquatic
environment and influence the water supply. A carbonate basin with deposits of high-arsenic coal in Xingren County, southwestern
China, was chosen to study the behavior of As and other chemical constituents along a river receiving AMD. Heavy metals (Fe,
Mn) and major ions such as (Ca2+, Mg2+, Cl−, SO4
2−) in surface water, and As in sediment and surface water were analyzed. It was found that high concentrations of SO4
2− (1,324–7,560 mg/L) and Fe (369–1,472 mg/L) in surface water were mainly controlled by the interactions between water and
rocks such as the oxidation of pyrite in the local coal seams, precipitation and adsorption of iron minerals. Although ubiquitous
carbonate minerals in the bedrock and the riverbeds, low pH (<3) water was maintained until 2 km downstream from the AMD source
due to the Fe(hydro)oxide minerals coating on the surface of carbonate minerals to restrain the neutralization of acidic water.
Moreover, the formation of Fe(hydro)oxide precipitations absorbed As was dominated the attenuation of As from water to sediment.
Whereas, the dilution also played an important role in decrease of As in river water. 相似文献
9.
Hydrogeochemical and Stable Isotope Characteristics of the River Idrijca (Slovenia), the Boundary Watershed Between the Adriatic and Black Seas 总被引:1,自引:0,他引:1
The hydrogeochemical and isotope characteristics of the River Idrijca, Slovenia, where the world’s second largest mercury
(Hg) mine is located, were investigated. The River Idrijca, a typical steep mountain river, has an HCO3
−–Ca2+–Mg2+ chemical composition. Its Ca2+/Mg2+ molar ratio indicates that dolomite weathering prevails in the watershed. The River Idrijca and its tributaries are oversaturated
with respect to calcite and dolomite. The pCO2 pressure is up to 13 times over atmospheric pressure and represents a source of CO2 to the atmosphere. δ18O values in river water indicate primary control from precipitation and enrichment of the heavy oxygen isotope of infiltrating
water recharging the River Idrijca from its slopes. The δ13CDIC values range from −10.8 to −6.6‰ and are controlled by biogeochemical processes in terrestrial environments and in the stream:
(1) exchange with atmospheric CO2, (2) degradation of organic matter, (3) dissolution of carbonates, and (4) tributaries. The contributions of these inputs
were calculated according to steady state equations and are estimated to be—11%:19%:30%:61% in the autumn and 0%:26%:39%:35%
in the spring sampling seasons. 相似文献
10.
Stable Carbon Isotope Biogeochemistry and Anthropogenic Impacts on Karst Ground Water, Zunyi, Southwest China 总被引:2,自引:0,他引:2
Si-Liang Li Cong-Qiang Liu Yun-Chao Lang Faxiang Tao Zhiqi Zhao Zhihua Zhou 《Aquatic Geochemistry》2008,14(3):211-221
Natural and anthropogenic impacts on karst ground water, Zunyi, Southwest China, are discussed using the stable isotope composition
of dissolved inorganic carbon and particulate organic carbon, together with carbon species contents and water chemistry. The
waters can be mainly characterized as HCO3–Ca type, HCO3 · SO4–Ca type, or HCO3 · SO4–Ca · Mg type, according to mass balance considerations. It is found that the average δ13CDIC values of ground waters are higher in winter (low-flow season) than in summer (high-flow season). Lower contents of dissolved
inorganic carbon (DIC) and lower values of δ13CDIC in summer than in winter, indicate that local rain events in summer and a longer residence time of water in winter play an
important role in the evolution of ground water carbon in karst flow systems; therefore, soil CO2 makes a larger contribution to the DIC in summer than in winter. The range of δ13CDIC values indicate that dissolved inorganic carbon is mainly controlled by the rate of carbonate dissolution. The concentrations
of dissolved organic carbon and particulate organic carbon in most ground water samples are lower than 2.0 mg C L−1 and 0.5 mg C L−1, respectively, but some waters have slightly higher contents of organic carbon. The waters with high organic carbon contents
are generally located in the urban area where lower δ13CDIC values suggest that urbanization has had an effect on the ground water biogeochemistry and might threaten the water quality. 相似文献
11.
Environmental geochemistry and quality assessment of mine water of Jharia coalfield,India 总被引:1,自引:0,他引:1
Abhay Kumar Singh M. K. Mahato B. Neogi B. K. Tewary A. Sinha 《Environmental Earth Sciences》2012,65(1):49-65
A long mining history and unscientific exploitation of Jharia coalfield caused many environmental problems including water
resource depletion and contamination. A geochemical study of mine water in the Jharia coalfield has been undertaken to assess
its quality and suitability for domestic, industrial and irrigation uses. For this purpose, 92 mine water samples collected
from different mining areas of Jharia coalfield were analysed for pH, electrical conductivity (EC), major cations (Ca2+, Mg2+, Na+, K+), anions (F−, Cl−, HCO3
−, SO4
2−, NO3
−), dissolved silica (H4SiO4) and trace metals. The pH of the analysed mine water samples varied from 6.2 to 8.6, indicating mildly acidic to alkaline
nature. Concentration of TDS varied from 437 to 1,593 mg L−1 and spatial differences in TDS values reflect the variation in lithology, surface activities and hydrological regime prevailing
in the region. SO4
2− and HCO3
− are dominant in the anion and Mg2+ and Ca2+ in the cation chemistry of mine water. High concentrations of SO4
2− in the mine water of the area are attributed to the oxidative weathering of pyrites. Ca–Mg–SO4 and Ca–Mg–HCO3 are the dominant hydrochemical facies. The drinking water quality assessment indicates that number of mine water samples
have high TDS, total hardness and SO4
2− concentrations and needs treatment before its utilization. Concentrations of some trace metals (Fe, Mn, Ni, Pb) were also
found to be above the desirable levels recommended for drinking water. The mine water is good to permissible quality and suitable
for irrigation in most cases. However, higher salinity, residual sodium carbonate and Mg-ratio restrict its suitability for
irrigation at some sites. 相似文献
12.
Interaction of acid mine drainage with waters and sediments at the Corona stream, Lousal mine (Iberian Pyrite Belt, Southern Portugal) 总被引:1,自引:0,他引:1
E. Ferreira da Silva C. Patinha P. Reis E. Cardoso Fonseca J. X. Matos J. Barrosinho J. M. Santos Oliveira 《Environmental Geology》2006,50(7):1001-1013
This study investigates the geochemical characteristics of the acid mine drainage discharged from the abandoned mine adits and tailing piles in the vicinity of the Lousal mine and evaluates the extent of pollution on water and on the stream sediments of the Corona stream. Atmospheric precipitation interacting with sulphide minerals in exposed tailings produces runoff water with pH values as low as 1.9–2.9 and high concentrations of
(9,249–20,700 mg l−1), Fe (959–4,830 mg l−1) and Al (136–624 mg l−1). The acidic effluents and mixed stream water carry elevated Cu, Pb, Zn, Cd and As concentrations that exceed the water quality standards. However, the severity of contamination generally decreases 4 km downstream of the source due to mixing with fresh waters, which causes the dilution of dissolved toxic metals and neutralization of acidity. Some natural attenuation of the contaminants also occurs due to the general reduced solubility of most trace metals, which may be removed from solution, by either co-precipitation or adsorption to the iron and aluminium precipitates. 相似文献
13.
Hydrogeochemical processes in the groundwater environment of Heihe River Basin,northwest China 总被引:5,自引:0,他引:5
Zhu Gaofeng Su Yonghong Huang Chunlin Feng Qi Liu Zhiguang 《Environmental Earth Sciences》2010,60(1):139-153
The Heihe River Basin is a typical arid inland river basin for examining stress on groundwater resources in northwest China.
The basin is composed of large volumes of unconsolidated Quaternary sediments of widely differing grain size, and during the
past half century, rapid socio-economic development has created an increased demand for groundwater resources. Understanding
the hydrogeochemical processes of groundwater and water quality is important for sustainable development and effective management
of groundwater resources in the Heihe River basin. To this end, a total of 30 representative groundwater samples were collected
from different wells to monitor the water chemistry of various ions and its quality for irrigation. Chemical analysis shows
that water presents a large spatial variability of chemical facies (SO4
2−–HCO3−, SO4
2−–Cl−, and Cl−–SO4
2−) as groundwater flow from recharge area to discharge area. The ionic ratio indicates positive correlation between the flowing
pairs of parameters: Cl− and Na+(r = 0.95), SO4
2− and Na+ (r = 0.84), HCO3
− and Mg2+(r = 0.86), and SO4
2− and Ca2+ (r = 0.91). Dissolution of minerals, such as halite, gypsum, dolomite, silicate, and Mirabilite (Na2SO4·10H2O) in the sediments results in the Cl−, SO4
2−, HCO3
−, Na+, Ca2+ and Mg2+ content in the groundwater. Other reactions, such as evaporation, ion exchange, and deposition also influence the water composition.
The suitability of the groundwater for irrigation was assessed based on the US Salinity Laboratory salinity classification
and the Wilcox diagram. The results show that most of the groundwater samples are suitable for irrigation uses barring a few
locations in the dessert region in the northern sub-basin. 相似文献
14.
The Removal of Dissolved Metals by Hydroxysulphate Precipitates during Oxidation and Neutralization of Acid Mine Waters, Iberian Pyrite Belt 总被引:4,自引:0,他引:4
J. Sánchez España E. López Pamo E. Santofimia Pastor J. Reyes Andrés J. A. Martín Rubí 《Aquatic Geochemistry》2006,12(3):269-298
This study examines the removal of dissolved metals during the oxidation and neutralization of five acid mine drainage (AMD)
waters from La Zarza, Lomero, Esperanza, Corta Atalaya and Poderosa mines (Iberian Pyrite Belt, Huelva, Spain). These waters
were selected to cover the spectrum of pH (2.2–3.5) and chemical composition (e.g., 319–2,103 mg/L Fe; 2.85–33.3 g/L SO4=) of the IPB mine waters. The experiments were conducted in the laboratory to simulate the geochemical evolution previously
recognized in the field. This evolution includes two stages: (1) oxidation of dissolved Fe(II) followed by hydrolysis and
precipitation of Fe(III), and (2) progressive pH increase during mixing with fresh waters. Fe(III) precipitates at pH < 3.5
(stages 1 and 2) in the form of schwertmannite, whereas Al precipitates during stage 2 at pH 5.0 in the form of several hydroxysulphates
of variable composition (hydrobasaluminite, basaluminite, aluminite). During these stages, trace elements are totally or partially
sorbed and/or coprecipitated at different rates depending basically on pH, as well as on the activity of the SO4=
anion (which determines the speciation of metals). The general trend for the metals which are chiefly present as aqueous
free cations (Pb2+, Zn2+, Cu2+, Cd2+, Mn2+, Co2+, Ni2+) is a progressive sorption at increasing pH. On the other hand, As and V (mainly present as anionic species) are completely
scavenged during the oxidation stage at pH < 3.5. In waters with high activities (> 10−1) of the SO 4= ion, some elements like Al, Zn, Cd, Pb and U can also form anionic bisulphate complexes and be significantly sorbed at pH
< 5. The removal rates at pH 7.0 range from around 100% for As, V, Cu and U, and 60–80% for Pb, to less than 20% for Zn, Co,
Ni and Mn. These processes of metal removal represent a significant mechanism of natural attenuation in the IPB. 相似文献
15.
Chemical and Strontium Isotopic Compositions of the Hanjiang Basin Rivers in China: Anthropogenic Impacts and Chemical Weathering 总被引:1,自引:0,他引:1
The Hanjiang River, the largest tributaries of the Changjiang (Yangtze) River, is the water source area of the Middle Route
of China’s South-to-North Water Transfer Project. The chemical and strontium isotopic compositions of the river waters are
determined with the main purpose of understanding the contribution of chemical weathering processes and anthropogenic inputs
on river solutes, as well as the associated CO2 consumption in the carbonate-dominated basin. The major ion compositions of the Hanjiang River waters are characterized by
the dominance of Ca2+ and HCO3
−, followed by Mg2+ and SO4
2−. The increase in TDS and major anions (Cl−, NO3
−, and SO4
2−) concentrations from upstream to downstream is ascribed to both extensive influences from agriculture and domestic activities
over the Hanjiang basin. The chemical and Sr isotopic analyses indicate that three major weathering sources (dolomite, limestone,
and silicates) contribute to the total dissolved loads. The contributions of the different end-members to the dissolved load
are calculated with the mass balance approach. The calculated results show that the dissolved load is dominated by carbonates
weathering, the contribution of which accounts for about 79.4% for the Hanjiang River. The silicate weathering and anthropogenic
contributions are approximately 12.3 and 6.87%, respectively. The total TDS fluxes from chemical weathering calculated for
the water source area (the upper Hanjiang basin) and the whole Hanjiang basin are approximately 3.8 × 106 and 6.1 × 106 ton/year, respectively. The total chemical weathering (carbonate and silicate) rate for the Hanjiang basin is approximately
38.5 ton/km2/year or 18.6 mm/k year, which is higher than global mean values. The fluxes of CO2 consumption by carbonate and silicate weathering are estimated to be 56.4 × 109 and 12.9 × 109 mol/year, respectively. 相似文献
16.
Hydrogeochemical and isotopic investigation of the Bursa-Oylat thermal waters, Turkey 总被引:1,自引:1,他引:0
Suzan Pasvano?lu 《Environmental Earth Sciences》2011,64(4):1157-1167
The Oylat spa is located 80 km southeast of Bursa and 30 km south of Ineg?l in the Marmara region. With temperature of 40°C
and discharge of 45 l/s, the Oylat main spring is the most important hot water spring of the area. Southeast of the spa the
Forest Management spring has a temperature of 39.4°C and discharge of 2 l/s. The G?z spring 2 km north of the spa, which is
used for therapy of eye disease, and cold waters of the Saadet village springs with an acidic character are the further important
water sources of the area. EC values of Main spring and Forest Management hot spring (750–780 μS/cm) are lower than those
of Saadet and G?z spring waters (2,070–1,280 μS/cm) and ionic abundances are Ca > Na + K > Mg and SO4 > HCO3 > Cl. The Oylat and Sızı springs have low Na and K contents but high Ca and HCO3 concentrations. According to AIH classification, these are Ca–SO4–HCO3 waters. Based on the results of δ18O, 2H and 3H isotope analyses, the thermal waters have a meteoric origin. The meteoric water infiltrates along fractures and faults,
gets heated, and then returns to surface through hydrothermal conduits. Oylat waters do not have high reservoir temperatures.
They are deep, circulating recharge waters from higher enhanced elevations. δ13CDIC values of the Main spring and Forest Management hot spring are −6.31 and −4.45‰, respectively, indicating that δ13C is derived from dissolution of limestones. The neutral pH thermal waters are about +18.7‰ in δ34S while the sulfate in the cold waters is about +17‰ (practically identical to the value for the neutral pH thermal waters).
However, the G?z and Saadet springs (acid sulfate waters) have much lower δ34S values (~+4‰). 相似文献
17.
Acid mine drainage is a major source of water pollution in the Sarcheshmeh porphyry copper mine area. The concentrations of heavy metals and rare earth elements (REEs) in the host rocks, natural waters and acid mine drainage (AMD) associated with mining and tailing impoundments are determined. Contrary to the solid samples, AMDs and impacted stream waters are enriched in middle rare earth elements (MREEs) and heavy rare earth elements (HREEs) relative to light rare earth elements (LREEs). This behavior suggests that REE probably fractionate during sulfide oxidation and acid generation and subsequent transport, so that MREE and HREE are preferentially enriched. Speciation modeling predict that the dominant dissolved REE inorganic species are Ln3+, Ln(SO4)2−, LnSO4+, LnHCO32+, Ln(CO3)2− and LnCO3+. Compared to natural waters, Sarcheshmeh AMD is enriched in REEs and SO42−. High concentrations of SO42− lead to the formation of stable LnSO4+, thereby resulting in higher concentrations of REEs in AMD samples. The model indicates that LnSO4+ is the dissolved form of REE in acid waters, while carbonate and dicarbonate complexes are the most abundant dissolved REE species in alkaline waters. The speciation calculations indicate that other factors besides complexation of the REE's, such as release of MREE from dissolution and/or desorption processes in soluble salts and poorly crystalline iron oxyhydroxy sulfates as well as dissolution of host rock MREE-bearing minerals control the dissolved REE concentrations and, hence, the MREE-enriched patterns of acid mine waters. 相似文献
18.
On the basis of the hydrogeology of the Dousitu River drainage basin, the changes of water flow rate, δ18O and δD along the Dousitu River are discussed according to measured and analytical results. Changes of flow rate along the
Dousitu River agree well with groundwater level contours and the recharge and discharge of groundwater to the river. When
compared with other types of water in the area, it is obvious that the 18O and D of river waters have experienced evaporation. The changes of δ18O and δD along the Dousitu River are mainly caused by combined effects of groundwater recharge and river water evaporation.
The recharge of groundwater makes δ18O and δD of the river water decrease. Evaporation makes δ18O and δD of the river water increase. The evaporation fractions of the river water are calculated using the kinetic fractionation
theory. Results showed as much as 10–30% of water was evaporated in different segments of Dousitu River. 相似文献
19.
Badia Chulli Aysen Davraz Jalila Makni Mourad Bedir Hamed Ben Dhia 《Environmental Earth Sciences》2012,66(1):1-16
The Sfax Basin in eastern Tunisia is bounded to the east by the Mediterranean Sea. Thermal waters of the Sfax area have measured
temperatures of 23–36°C, and electrical conductivities of 3,200 and 14,980 μS/cm. Most of the thermal waters are characterized
as Na–Cl type although there are a few Na–SO4–Cl waters. They issue from Miocene units which are made up sands and sandstones interbedded with clay. The Quaternary sediments
cap the system. The heat source is high geothermal gradient which are determined downhole temperature measurements caused
by graben tectonics of the area. The results of mineral equilibrium modeling indicate that the thermal waters of the Sfax
Basin are undersaturated with respect to gypsum, anhydrite and fluorite, oversaturated with respect to kaolinite, dolomite,
calcite, microcline, quartz, chalcedony, and muscovite. Assessments from various chemical geothermometers, Na–K–Mg ternary
and mineral equilibrium diagrams suggest that the reservoir temperature of the Sfax area can reach up to 120°C. According
to δ18O and δ2H values, all thermal and cold groundwater is of meteoric origin. 相似文献
20.
The water and bed-sediment pollution status of the Padma River was determined by analysis of representative samples for selected
metals and ions. Water and bed-sediment samples were collected at a T-dam, Rajshahi, Bangladesh, for 7 months. Water and silt-metal
content analysis was performed using atomic absorption spectrophotometry or other analytical methods. The data showed the
variation of the metal ion-levels in water as follows: Ca 17.11–48.37 ppm, Na 17.51–20.09 ppm, K 1.00–3.60 ppm, Cr 2.80–7.00 ppm,
and SO4 4.17–5.48 ppm; in bed sediment, the levels were Cr 35–1050 ppm and Pb 12–48 ppm. The occurrence of Na, K and Ca was in the
normal range (US EPA permissible limit), but the levels of Cr in water were much higher than the permissible limit. The SO4 ion content was well below the pollution level. The concentration of Pb in the bed sediment was within the permissible limit
for the standard International Atomic Energy Agency (IAEA) Soil-5a, but the concentration of Cr in the bed sediment was significantly
higher than the permissible limit for the standard IAEA Soil-5a. Thus the Padma river water was polluted with Cr. The occurrence
of some ions showed a monthly variation.
Received: 19 August 1999 · Accepted: 12 October 1999 相似文献