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1.
A. N. Voronov 《Environmental Geology》2000,39(5):477-481
The Russian Federation has many aquifers and these possess a wide range of chemical compositions. In Russia about 300 mineral
water sources have been developed as spas and health resorts. More than 150 of them produce bottled mineral water. A brief
historical revue is given. The study of mineral waters in Russia began as far back as the reign of Peter the Great (1682–1725).
It has been prolonged by works of many Russian scientists.
The details of the chemical composition of the different types of Russian mineral waters and some geological aquifer peculiarities
are described. The most widely used classification of mineral waters in Russia is presented. The present condition of these
waters and the government standards laid down for their use are described. Examples of different mineral waters are given.
Received: 14 April 1998 / Accepted: 8 December 1998 相似文献
2.
Interstitial water and hydrochemistry of a mangrove forest and adjoining water system, south west coast of India 总被引:1,自引:0,他引:1
Eh, pH, salinity, total alkalinity, dissolved O2, NO2
–, PO4
–3, SiO2 and NH4
+ of waters from a mangrove forest, an estuary and a creek connecting the mangrove forest and the estuary have been measured.
Further, the chemistry of interstitial waters of surficial and core sediments from the mangrove forest have been analyzed
for the above parameters, except dissolved oxygen. To understand the flux of nutrients from the mangrove forest to the adjoining
estuary, creek waters were monitored during tidal phases. PO4
–3, SiO2 and NH4
+ were found to be at elevated levels in mangrove waters whereas NO2
– shows no variation compared to the estuary. Dissolved O2 is low in mangrove waters. PO4
–3, NH4
+ and SiO2 are several times higher in interstitial waters than in overlying waters. Several fold enrichment of PO4
–3, NH4
+ and, to some extent, SiO2 were measured in creek waters during ebbing relative to flooding, indicating that mangroves act as a perennial source for
the above nutrients.
Received: 26 May 1998 · Accepted: 21 July 1998 相似文献
3.
Thermal and mineral waters in north-eastern Slovenia 总被引:2,自引:0,他引:2
The Mura basin in north-eastern Slovenia is made up of two depressions, developed during the Late Neogene and Early Pliocene
all within a widespread system of Pannonian basins. Both depressions are characterized by the occurrence of thermal waters
of somewhat different hydrogeochemical character. Radgona depression is in the northern part of the basin and reaches depths
of about 2 km. Thermal waters are generally dominated by sodium-bicarbonate, not related to the age of an aquifer, its wallrock
composition, the type of porosity or total concentration of dissolved solids. Locally, sulphate-rich waters are encountered,
and they are related to the presence of gypsum in the rocks of pre-Tertiary basement. The adjacent Ljutomer depression is
over 4 km deep and comprises compartments with stagnant or semi-stagnant aquifers. Herein saline waters predominate, even
in the aquifers of carbonate composition and abundant CO2 gas. In shallower, unconsolidated, intergranular aquifers sodium-bicarbonate waters predominate. Thermal aquifers of this
type are very important to the economy of the region, but they are also subjected to overexploitation which is reflected in
time-dependent changes of dynamic pressures, temperature, conductance, salinity, pH and concentration of major ions, trace
elements, dissolved gasses, and total organic carbon. Mineral waters occur in shallow aquifers or springs in marginal areas
of the Radgona depression. Bicarbonate waters are dominated by calcium, or both calcium and sodium. Some mineral waters are
formed mainly by penetration of CO2 gas into shallow aquifers and consequent water–rock interaction. Composition of some mineral waters indicate their possible
evolution from thermal waters which have risen from central parts of the Radgona depression along deep-seated faults, and
have been modified by cooling and mixing processes.
Received: 30 November 1998 · Accepted: 22 March 1999 相似文献
4.
Keith Harries 《Geoforum》2006,37(3):404-416
A salient characteristic of the geography of crime in the US is the presence of extremely sharp geographic variations. These variations may be significant indicators of local environmental inequalities and may have implications for fear of crime and crime contagion, and may also be indicators of potential or actual neighborhood instability. Such micro-level variations are not generally apparent on small scale maps of urban crime. Previously, micro-level analysis of this gradient phenomenon has been inhibited by the confluence of large volumes of data over large areas, a plethora of possible boundaries that might be used for the purpose of data aggregation, and practical difficulties in the identification of gradients in the context of small units of analysis. The present study attempts to identify steep crime gradients and to characterize the physical and social circumstances under which they occur. Analysis was based on 97,880 geocodable incidents reported in 2000 in Baltimore County, Maryland. Crime densities were calculated for 5324 census blocks that experienced at least one crime incident. A steep gradient for the purpose of this research was the juxtaposition of blocks in the highest and lowest quintiles in terms of crime density. Using residential and commercial land uses as a filter, some 259 blocks satisfied the gradient criterion. Further analysis linked these blocks to their parent block groups for the purpose of identifying their social attributes. In addition, six clusters of blocks were investigated in the field. A typology of adjacencies identified six categories. 相似文献
5.
Waters from five cenotes that are currently being used for aquatic recreational activities and that lie along the Cancun–Tulum
touristic corridor, Mexico, were evaluated hydrochemically to determine whether the cenotes may be considered as potential
drinking-water sources. Several parameters exceed the Mexican Drinking Water Standards (MDWS), but since they do not pose
a significant health threat, four of the five cenotes may be used as drinking-water sources. The common contaminants in the
Yucatan Peninsula, fecal coliforms and nitrate, are in most cases below the MDWS (0–460 MPN/100 ml and 0.31–1.18 mg/L, respectively).
Although these four cenotes meet the MDWS, a careful groundwater management policy needs to be developed to avoid contamination
(fecal and nitrates) and salt-water intrusion.
Received, October 1996 Revised, June 1997; March 1998 Accepted, July 1997 相似文献
6.
Two karst areas within Permian and Triassic carbonate rocks of the Codru Moma Mountains in the northwestern part of Romania
yield thermal waters. Major karst springs occur where groundwater flow is intercepted by hydraulic barriers, which also results
in the movement of water from deeper levels. At Moneasa, thermal groundwater rises along faults and fractures associated with
a thrust, and at Vascau Town, water rises along faults marginal to the Beius Basin. Geochemistry suggests that the thermal
component of the Moneasa groundwaters is derived from dolomites and that at least a proportion of the Vascau thermal waters
originates from deeply buried Permian sandstones.
Received, August 1999 / Revised, March 2000 / Accepted, March 2000 相似文献
7.
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
8.
M. H. Abdullah M. B. Mokhtar S. H. J. Tahir A. B. T. Awaluddin 《Environmental Geology》1997,29(1-2):112-117
Sipadan Island is a small oceanic island with limited storage of fresh groundwater. A study was carried out to determine
the effect of tidal change on the groundwater quality of such an island using temperature, dissolved oxygen content, conductivity,
salinity, and pH values as indicators. Overall, the results indicated that the groundwater quality changes with tides, but
the trends of fluctuation differs between the observed parameters. It was found that the percentages of changes during the
period of study were 0.8% (temperature), 53% (dissolved oxygen), 61% (conductivity), 58% (salinity), and 1.7% (pH) at the
centre of the island; and 0.9% (temperature), 33% (dissolved oxygen), 40% (conductivity), 42% (salinity), and 9% (pH) at a
station 120 m from the coast, based on 2.9-m and 2.8-m tidal ranges at each station.
Received: 5 July 1995 · Accepted: 6 November 1995 相似文献
9.
J. Pacheco Luis Marín Armando Cabrera Birgit Steinich Oscar Escolero 《Environmental Geology》2001,40(6):708-715
The nitrate concentration in 12 water-supply wells were monitored for the period April 1992 to March 1993. Each water-supply
well was sampled once a month. The nitrate concentrations in the 12 wells ranged from 7 to 156 mg/l. Two water-supply wells
(Chacsinkin and Peto) showed concentrations that reached 3.5 times the maximum permissible limit for the Drinking Water Standard
(45 mg/l). A third water-supply well (Akil) exceeds the norm for 7 out of 12 months. The use of nitrogen-rich fertilizers
are responsible for high nitrate concentrations in groundwater in the southern part of Yucatan, Mexico where intensive agricultural
practices exist.
Received: 14 December 1999 · Accepted: 2 May 2000 相似文献
10.
Thermomineral waters of Ca-chloride composition: review of diagnostics and of brine evolution 总被引:1,自引:0,他引:1
E. Rosenthal 《Environmental Geology》1997,32(4):245-250
Ca-chloride waters are defined as those in which Q=rCa/r(SO4+HCO3)>1, rNa/rCl<0.80, rMg/rCa<0.5 and wCl/wBr<286 (r=meq l–1 and w=mg l–1). Throughout the last 50 years, different models for the formation of such waters have been suggested. These models include:
(1) filtration through semipermeable membranes under conditions of highly compacted argillaceous sediments, (2) deaquation
of seawater by evaporation and/or by freezing followed by dolomitization, (3) hydrolysis of plagioclase and biotites in igneous
metamorphic rock masses, (4) radiolytic modification of residual metamorphic fluids, and (5) dissolution of chalks followed
by ion exchange on smectites. The better understanding of processes and of natural environments leading to the evolution and
natural occurrence of such brines, is imperative for the prospection and further sustained exploitation of such waters.
Received: 11 October 1996 · Accepted: 24 February 1997 相似文献
11.
For the fibrous zeolites natrolite, Na2[Al2Si3O10]·2H2O, mesolite, Na2Ca2[Al2Si3O10]3·8H2O, and scolecite, Ca[Al2Si3O10]·3H2O, with topologically identical aluminosilicate framework structures, accurate single-crystal X-ray diffraction data have
been analyzed by least-squares refinements using generalized scattering factor (GSF) models. The final agreement indices were
R(F ) = 0.0061, 0.0165, and 0.0073, respectively. Ensuing calculations of static deformation [Δρ(r)], and total, [ρ(r)], model electron density distributions served to study chemical bonding, in particular by topological electron density analyses
yielding bond critical point (bcp) properties and in situ cation electronegativities. The results for 32 SiO, 24 AlO, 14 CaO,
and 12 NaO unique bonds are compiled and analyzed in terms of both mean values and correlations between bond lengths, bonded
oxygen radii, bcp densities, curvatures at the bcps, and electronegativities. Comparison with recent literature data obtained
from both experimental electron density studies on minerals and model calculations for geometry-optimized molecules shows
that the majority of the present findings conforms well with chemical expectation and with the trends observed from molecular
modeling. For the SiO bond, the shared interaction is indicated to increase with decreasing bond length, whereas the AlO bond
is of distinctly more polar nature, as is the NaO bond compared to CaO. Also, the observed ranges of the Si and Al in situ
electronegativities and their mean electronegativities agree well with both Pauling's values and model calculation results,
and statistically significant correlations are obtained which are consistent with trends described for oxide and nitride molecules.
Received: 10 May 1999 / Revised, accepted: 14 September 1999 相似文献
12.
Proposed groundwater withdrawals in the San Luis Valley of Colorado may lower the water table in Great Sand Dunes National
Monument. In response, the National Park Service initiated a study that has produced a generalized conceptual model of the
hydrologic system in order to assess whether a lowering of the water table might decrease the surface flow of lower Medano
Creek. Based upon information obtained during the drilling of several boreholes, there appear to be five important hydrostratigraphic
units underlying lower Medano Creek within the upper 30 m of the ground surface: 1. a perched aquifer overlying an aquitard
located between about 5 and 6 m below the ground surface; 2. the aquitard itself; 3. an unconfined aquifer located between
the upper and lower aquitards; 4. an aquitard located between about 27 and 29 m below the ground surface; and 5. a confined
underlying the lower aquitard. Because the areal extent of the aquitards cannot be determined from the borehole data, a detailed
conceptual model of the hydrogeologic system underlying lower Medano Creek cannot be developed. However, a generalized conceptual
model can be envisioned that consists of a complex system of interlayered aquifers and leaky aquitards, with each aquifer
having a unique hydraulic head. Water levels in the perched aquifer rise rapidly to their annual maximum levels in response
to the arrival of the flow terminus of Medano Creek during the spring runoff event, and the location of the flow terminus
is directly dependent upon the discharge of the creek. Water levels in the deeper, non-perched aquifers do not appear to fluctuate
significantly in response to the arrival of the flow terminus, demonstrating that it is unlikely that the proposed groundwater
withdrawals will decrease the surface flow of lower Medano Creek.
Received: 27 December 1995 · Accepted: 20 February 1996 相似文献
13.
A field study was conducted to assess variations in physico-chemical characteristics of water of the springs located within
the boundary of a Central Himalayan town where the springwater is used for drinking purposes. Monitoring of 12 springs was
carried out for three seasons (winter, summer and monsoon). The results indicate direct influence of unplanned sewage disposal
on the springwater quality as reflected by significant regional variations in the concentration of nitrates, chlorides, sulfates,
sulfides and electrical conductivity. Population density varies within the town from 3110 to 14 137 persons/km–2 and has direct relationship with water quality. Springs located in the densely populated area had higher concentrations of
all these compounds. Concentrations of nitrates up to 60 ppm were observed in some springs, making water unsuitable for human
consumption. No significant changes were observed in springwater quality during different seasons.
Received: 3 February 1995 · Accepted: 27 February 1996 相似文献
14.
Aquifers in the arid alluvial basins of the southwestern U.S. are recharged predominantly by infiltration from streams and
playas within the basins and by water entering along the margins of the basins. The Tucson basin of southeastern Arizona is
such a basin. The Santa Catalina Mountains form the northern boundary of this basin and receive more than twice as much precipitation
(ca. 700 mm/year) as does the basin itself (ca. 300 mm/year). In this study environmental isotopes were employed to investigate
the migration of precipitation basinward through shallow joints and fractures. Water samples were obtained from springs and
runoff in the Santa Catalina Mountains and from wells in the foothills of the Santa Catalina Mountains. Stable isotopes (δD
and δ18O) and thermonuclear-bomb-produced tritium enabled qualitative characterization of flow paths and flow velocities. Stable-isotope
measurements show no direct altitude effect. Tritium values indicate that although a few springs and wells discharge pre-bomb
water, most springs discharge waters from the 1960s or later.
Received, February 1997 · Revised, September 1997 · Accepted, September 1997 相似文献
15.
Humboldt, Arago, and the temperature of groundwater 总被引:1,自引:0,他引:1
Stanley N. Davis 《Hydrogeology Journal》1999,7(5):501-503
16.
Duke U. Ophori 《Hydrogeology Journal》1998,6(2):193-203
Flow of groundwater with variable density and viscosity was simulated at the Atikokan Research Area (ARA) in northwestern
Ontario, Canada. An empirical viscosity–concentration equation was modified to include total-dissolved-solids (TDS) data from
the ARA. The resulting equation was used successfully to estimate reasonably accurate viscosity values over the expected range
of temperature and concentration, in comparison with experimental values derived for sodium chloride solutions. A three-dimensional
finite-element code, MOTIF, developed by Atomic Energy of Canada Limited, was used in the simulations. The inclusion of the
effects of depth-increasing temperature and TDS-dependent fluid-density distribution, while maintaining only a temperature-dependent
viscosity relationship in a simulation, resulted in a more penetrative flow against expected buoyancy effects (i.e., the physics
of the system was not honored). Accounting for concentration in the viscosity equation caused water to be less penetrative
and more in accordance with the expected physics of the system. A conclusion is that fluid concentration should be considered
simultaneously in calculating the density and viscosity of a fluid during modeling of variable-density flow in areas underlain
by fluids with high TDS. Results of simulations suggest that both flow directions and magnitudes should be employed simultaneously
during the calibration of a model. Large-scale groundwater movement in the ARA may be analyzed with carefully selected vertical
no-flow boundaries. By incorporating the geothermal temperature gradient, groundwater recharge increases by 12%; thus, this
gradient plays a significant role in groundwater flow at the ARA. Variability in the fluid concentration at the ARA neither
decreases nor increases recharge into the groundwater system. The hypothesis that an isolated continuous regional flow system
may exist at depth in the ARA is not supported by these simulations.
Received, September 1996 Revised, September 1997, February 1998 Accepted, February 1998 相似文献
17.
Slovakia has many areas rich in thermal waters one of which is the Hornonitrianska kotlina depression. At four localities
three types of waters are found. The first belongs to the Ca–Mg–HCO3 type with T.D.S. 0.7 g/l, the second to the Ca–Mg–SO4 type with T.D.S. 1.37–2.01 g/l and the third to the Ca–Mg–SO4–HCO3 type with T.D.S. 0.97 g/l. Discharge at individual localities varies up to 30 l/s and temperatures of water reach 32.5–66.6 °C.
The waters are predominantly used for healing, rehabilitation purposes, recreation and heating.
Received: 8 March 1999 · Accepted: 7 June 1999 相似文献
18.
Hydrochemical evolution and environmental features of Salso River catchment, central Sicily (Italy) 总被引:2,自引:0,他引:2
A hydrogeochemical study of the Salso River highlighted the chemical and isotopic space-time evolution along its flow path
and the main contamination processes. Within the basin, three different hydrogeochemical facies have been individuated: (1)
Ca-Mg-HCO3, (2) Ca-Mg-SO4 and (3) Na-Cl. The first facies reflects the chemical composition of the groundwaters hosted in the carbonate reliefs that
belong to the Madonie Mountains. The second and the third facies are the result of the interaction processes between surface
waters and the gypsum and salty clays, respectively. Two pollution sources have been also located in the basin downstream
from the salt mine and downstream from a discharge area of wastewater from the town of Gangi. On the basis of the location
of natural and anthropogenic pollution sources, the waters available for drinking and irrigation use are also indicated.
Received: 16 July 1999 · Accepted: 22 December 1999 相似文献
19.
Tomás Morales-Juberías Martín Olazar Jose María Arandes Pedro Zafra Iñaki Antigüedad Félix Basauri 《Environmental Geology》1997,30(3-4):143-151
A model based on numerical solutions, which allows for solving the dispersion equation under variable recharge and velocity conditions, is developed to simulate solute transport in conduit flow aquifers during flow recession periods. As an example, the evolution of a tracer in the little known karst conduit that links the sinking stream of Oma valley to the Olalde spring is investigated in the karstic region of Santa Eufemia-Ereñozar (Basque Country, Spain). The model, with different hypothetical structures, allows for obtaining series of tracer breakthrough curves, which are fitted to experimental data using an optimization algorithm. These results, although they can be used to simulate the tracer evolution between the two points considered, do not allow for determining the internal structure and spatial disposition of contributions in the aquifer. 相似文献
20.
M. Ramakrishna Reddy N. Janardhana Raju Y. Venkatarami Reddy T. V. K. Reddy 《Environmental Geology》2000,39(3-4):342-352
Intensive application of surface water in command areas of irrigation projects is creating water logging problems, and the
increase of groundwater usage in agriculture, industry and domestic purposes (through indiscriminate sinking of wells) is
causing continuous depletion of water levels, drying up of wells and quality problems. Thus the protect aquifers to yield
water continuously at economical cost, the management of water resources is essential. Integrated geological, hydrological
(surface and groundwater) and geochemical aspects have been studied for the development and management of water resources
in drought-prone Cuddapah district. The main lithological units are crystallines, quartzites, shales and limestones. About
91 000 ha of land in the Cuddapah district is irrigated by canal water. A registered ayacut of about 47 000 ha is irrigated
by 1368 minor irrigation tanks. A total of 503 spring channels are identified in the entire district originating from the
rivers/streams, which has the capacity of irrigating about 8700 ha. The average seasonal rise in groundwater level is 7.32 m
in quartzites, 5.35 m in crystallines, 3.82 m in shales, 2.50 m in limestones and 2.11 m in alluvium. Large quantities of
groundwater are available in the mining areas which can be utilised and managed properly by the irrigation department/cultivators
for the irrigation practices. Groundwater assessment studies revealed that 584 million m3 of groundwater is available for future irrigation in the district. From the chemical analysis, the quality of groundwater
in various rock units is within the permissible limits for irrigation and domestic purposes, but at a few places the specific
conductance, chloride and fluoride contents are high. This may be due to untreated effluents, improper drainage system and/or
the application of fertilisers.
Received: 10 June 1998 · Accepted: 15 November 1998 相似文献