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1.
The use of statistical techniques in studying the causes of geochemical variations in aquifers can provide important results
which cannot be derived in other ways. In this study, data from the Wadi Shueib catchment area in Jordan is evaluated, using
principle component factor and multivariate factor analysis in order to better understand the variablility in groundwater
chemistry and evaluate the sources of pollution and the susceptibility of these aquifers to the different sources of pollution.
This study clearly demonstrates that these statistical techniques can help determine the various mechanisms causing chemical
variation in the aquifers and the relative susceptibility of each aquifer to different types of pollution.
Received: 13 March 1996 · Accepted: 18 June 1996 相似文献
2.
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
3.
Analyses of 126 samples collected from 18 dug wells in the shallow basaltic aquifer over a period of 7 months have revealed
spatial as well as temporal changes in the chemical properties of groundwater. While the temporal changes have been attributed
to dilution and concentration phenomena governed by climatic factors, the spatial variations in the geochemical characteristics
of groundwater appeared to be related to pollution due to effluents from the Mula Sugar Factory. The cause of groundwater
pollution is the effluent carried by a stream flowing through the area. Fluctuations in the groundwater table, influent water
quality character of the stream, less capacity to accommodate large volume of effluent and occurrence of zero base flow (under
natural conditions) in the stream are the factors favoring infiltration of constituents of waste water into the underlying
weathered basaltic aquifer. Pollutants have entered into the shallow aquifer by downward percolation through the zone of aeration
to form a recharge mound at the water table and, further, lateral movement below the water table. The plume of polluted groundwater
has a lateral extent of a few meters in the upstream area and more than 400 m on either side of the stream in the downstream
part. The zone of polluted groundwater has an areal extent of more than 3.5 km2. Groundwater is the only source available for drinking and agricultural purposes. It is recommended that the base of the
lagoons and the stream used for release of plant effluent should be waterproofed for the protection of groundwater in the
Sonai area.
Received: 30 April 1997 · Accepted: 23 September 1997 相似文献
4.
Anthropogenic activities create various contaminated leachate, which can migrate downward from the vadose zone to groundwater,
transferring contaminants, including some hazardous ones.
When these various sources of contamination influence the groundwater aquifer simultaneously, the effects of contamination
are enhanced.
The major concern of this study has been to determine whether the shape of a groundwater chlorograph might be the result of
such deterministic effects as accumulation of one or more particular processes of groundwater contamination, and how this
might relate to specific hydrological situations.
This study proposes a classification of groundwater contamination on the basis of properties of the main components of groundwater
quality graphs and the corresponding hydrogeological/environmental situation.
The study further suggests that contamination of groundwater in any hydrogeological situation (e.g. sea water) may be graphically
expressed.
A variety of chlorographs and nitrographs, representative of various groundwater aquifers sampled from a number of wells throughout
Israel attest to this.
The study thus indicates that groundwater quality graphs may be considered as a complementary tool for groundwater quality
control and better understanding aquifer situations. 相似文献
5.
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
6.
Portman Bay presents elevated quantities of metals and heavy metals in the sediments and rocky outcrops. The calcitic skeletons
of the sea urchins that live there present elevated concentrations of Mn, Fe, Zn, and Pb (249, 273, 32, and 59 ppm) in comparison
with control zones (beach of La Vila) where the concentrations for these elements are 5, 7, 8, and 2 ppm, respectively. Two
species of sea urchins have been studied: Paracentrotus lividus and Arbacia lixula. The different compositions between the plates and the spines of their skeletons have also been studied.
Received: 20 November 1995 · Accepted: 25 January 1996 相似文献
7.
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
8.
Chemical data are used to clarify the hydrogeological regime in the Mafraq area in northern Jordan, as well as to determine
the status of water quality in the area. Groundwater from the shallow aquifer in the Mafraq area can be divided into two major
groups according to geographical locations and chemical compositions. Water in the basaltic eastern part of the study area
is characterized by the dominance of chloride, sulfate, sodium, and potassium, whereas waters in the limestone aquifers in
the west are dominated by the same cations but have higher concentrations of bicarbonate. Stable isotopes show that the shallow
aquifers contain a single water type which originated in a distinct climatic regime. This water type deviates from the Global
Meteoric Water Line (MWL), as well as from the eastern Mediterranean meteoric water line. The waters are poor in tritium,
and thus can be considered generally older than 50 years. Chemical mass balance models suggest that water is moving from the
west towards the north of the study area. This suggests that waters from the different basins are separated from each other.
Degradation of water quality can be attributed to agricultural fertilizers in most cases, although the waste-water treatment
plant at Khirbet es Samra is a contributor to pollution in the southwestern part of the study area.
Received: 20 August 1997 · Accepted: 3 February 1998 相似文献
9.
An approach to studying heavy metal pollution caused by modern city development in Nanjing, China 总被引:8,自引:0,他引:8
Nanjing is currently one of the fastest developing regions in terms of construction and economy in China. Heavy metal pollution
is becoming more serious with the expansion of production and life scales. Four environmental units (highway, refinery, rubbish
dumps associated with human daily life, and shoal of the Yangtse River) were selected from the region according to the geneses
of the pollution to study and evaluate the distribution and mechanism of the contamination, the speciations of the polluting
elements, and the geneses of the pollution in the soils and sediments. The purposes of the study are to understand generally
the current situation and the cause of the pollution, and to provide a scientific basis to prevent and solve the pollution
problem. At the same time, it would be helpful to probe the effective way of studying heavy metal pollution resulting from
the development of modern cities and to accumulate data. It is indicated by the study that the heavy metals contained in the
soil of the environmental unit of the highway are Pb, Co and Cr; in the soil of the refinery Cr, V, Pb, Ni, and Co; in the
soil of the rubbish plot Co, Cu, and Sb; in the sediments of the shoal Pb, Co, Cu, and Ni. Fe-Mn oxide is given the first
place to the speciations in polluting heavy metals transmitted by air. Carbonate is more in speciations of polluting heavy
metals transmitted by water than in speciations of the metals transmitted by air. In the ten elements studied, Pb is most
directly poisonous to the plants in the region; Co and Cu are the next, and Ni is the least. Heavy metal pollution has been
occurring in the soils and sediments of the region and the situation will worsen if some effective measures are not taken.
Received: 18 October 1997 · Accepted: 3 February 1998 相似文献
10.
A proposed new diagram for geochemical classification of natural waters and interpretation of chemical data 总被引:14,自引:1,他引:13
D. K. Chadha 《Hydrogeology Journal》1999,7(5):431-439
A new hydrochemical diagram is proposed for classification of natural waters and identification of hydrochemical processes.
The proposed diagram differs from the Piper and expanded Durov diagrams in that the two equilateral triangles are omitted,
and the shape of the main study field is different. In addition, the proposed diagram can be constructed on most spreadsheet
software packages. The proposed diagram is constructed by plotting the difference in milliequivalent percentage between alkaline
earths and alkali metals, expressed as percentage reacting values, on the X axis; and the difference in milliequivalent percentage
between weak acidic anions and strong acidic anions, also expressed as percentage reacting values, on the Y axis. The milliequivalent
percentage differences from the X and Y co-ordinates are extended further into the main study sub-fields of the proposed diagram,
which defines the overall character of water. Examples of hydrochemical analyses of groundwater are given from Karnataka,
India, for each of the three types of diagrams, illustrating the applicability of the proposed diagram in four case histories
having different hydrogeochemical aspects. A comparison indicates that the proposed new diagram satisfies the basic requirement
for a suitable classification of natural waters, and it also can be effectively used for studies of hydrochemical processes.
Received, April 1998 / Revised, February 1999 / Accepted, April 1999 相似文献
11.
The Dawu well field, one of the largest in China, supplies most of the water for the Zibo City urban area in Shandong Province.
The field yields 522,400–535,400 m3/d from an aquifer in fractured karstic Middle Ordovician carbonate rocks. Much of the recharge to the aquifer is leakage
of surface water from Zihe Stream, the major drainage in the area. Installation of the Taihe Reservoir in 1972 severely reduced
the downstream flow in Zihe Stream, resulting in a marked reduction in the water table in the Dawu field. Since 1994, following
the installation of a recharge station on Zihe Stream upstream from the well field that injects water from the Taihe Reservoir
into the stream, the groundwater resources of the field have recovered. An average of 61.2×103 m3/d of groundwater, mostly from the Ordovician aquifer, is pumped from the Heiwang iron mine, an open pit in the bed of Zihe
Stream below the Taihe Reservoir. A stepwise regression equation, used to evaluate the role of discharge from the reservoir
into the stream, confirms that reservoir water is one of the major sources of groundwater in the mine.
Received, May 1998 / Revised, May 1999 / Accepted, June 1999 相似文献
12.
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
13.
A limiting factor in developing artificial recharge of groundwater is clogging of the soil surface and consequent reduction
of infiltration rates. In order to evaluate the degree of improving infiltration rates by scraping away various amounts of
the upper soil materials, a study was conducted at three artificial recharge sites (Kohrouyeh, Bagh-Sorkh, and Kachak) in
Isfahan Province, central Iran. Five treatments (T1–T5) were considered. Infiltration was measured: T1, on deposited sediment
layer; T2, after removing the sediments; T3, scraping of sediments and 5 cm of soil; T4, scraping of sediments and 10 cm of
soil; and T5, removing sediments and 15 cm of soil. Initial soil-moisture content of the sites ranged from 1.0–2.87% for Kohrouyeh,
1.18–3.47% for Bagh-Sorkh, and 1.89–3.93% for Kachak. The main texture of the soils was sandy loam. Clay particles have penetrated
to a depth of more than 40 cm in some of the recharge basins. A significant increase in final infiltration rate of T5 as compared
to T1 treatment was observed for all recharge sites. The final infiltration rates of T1 and T5 treatments for Kohrouyeh, Bagh-Sorkh,
and Kachak sites were 0.35, 7.9; 1.22, 12.3; and 0.93, 6.2 cm/h, respectively. The differences between infiltration rates
of T2, T3, and T4 treatments were not statistically significant. It is concluded that on average, the infiltration capacity
of the untreated recharge facilities have reached 20.3% of the original values, and that scraping the top sediment layer and
15 cm of topsoil could restore 68.3% of the initial infiltration capacity.
Received, July 1998 / Revised, April 1999, May 1999 / Accepted, June 1999 相似文献
14.
Laser ablation ICP-MS analysis of tree rings provides a rapid and sensitive method for investigating element concentrations
and fluctuations in trees along time profiles. Time profiles obtained from pine and birch trees from a strongly polluted area
in northwest Russia and a slightly polluted area at the Norwegian-Russian border show that single trees behave rather individualistically
in terms of heavy metal contents as observed in the yearly growth rings. The obtained profiles can not be linked to the pollution
history of the area. No correlation between pollution levels of the soils and observed metal content in tree rings can be
established.
Received: 6 September 1996 / Accepted: 18 November 1996 相似文献
15.
A long-term study on the chemistry of percolating waters in a very large touristic karst cave (Grotta Gigante, northern Italy)
was carried out in order to define recharge zones, flowpaths, and possible anthropogenic contamination from the neighboring
area. On the basis of a multivaried analysis of the chemical parameters, a discrimination of the dripping points was attempted.
Percolation waters whose recharge zone is in the northernmost sector of the cave appeared permanently affected by the anthropic
settlements and agricultural activity on the ground surface.
Received: 28 April 1997 · Accepted: 3 February 1998 相似文献
16.
Application of remote-sensing data to groundwater exploration: A case study of the Cross River State, southeastern Nigeria 总被引:12,自引:2,他引:10
The Cross River State, Nigeria, is underlain by the Precambrian-age crystalline basement complex and by rocks of Cretaceous
to Tertiary age. The exploration for groundwater in this area requires a systematic technique in order to obtain optimum results,
but the non-availability of funds and facilities has made it extremely difficult to carry out site investigations prior to
the drilling of water wells. Therefore, the failure rate is as high as 80%. In order to delineate areas that are expected
to be suitable for future groundwater development, black and white radar imagery and aerial photographs were used to define
some hydrological and hydrogeological features in parts of the study area. Lineament and drainage patterns were analysed using
length density and frequency. Lineament-length density ranges from 0.04–1.52; lineament frequency is 0.11–5.09; drainage-length
density is 0.17–0.94, and the drainage frequency is 0.16–1.53. These range of values reflect the differences in the probability
of groundwater potentials. Results were then used to delineate areas of high, medium, and low groundwater potential. Study
results also indicate that correlations exist between lineament and drainage patterns, lithology, water temperature, water
conductivity, well yield, transmissivity, longitudinal conductance, and the occurrence of groundwater.
Received, August 1994 · Revised, March 1996, June 1996 · Accepted, October 1996 相似文献
17.
José M. Marques Paula M. M. Carreira Luís Aires-Barros Rui C. Graça 《Environmental Geology》2000,40(1-2):53-63
At the northern part of the Portuguese mainland, the upflow zone of several hot and cold HCO3/Na/CO2-rich mineral waters is mainly associated with important NNE–SSW faults. Several geochemical studies have been carried out
on thermal and non-thermal hydromineral manifestations that occur along or near these long tectonic alignments. The slight
chemical differences that exist between these meteoric hot and cold HCO3/Na/CO2-rich mineral waters seem to be mainly caused by CO2. δ13C(TIDC) values observed in these groundwaters range between –6.00 and –1.00‰ versus V-PDB (V denotes Vienna, the site of the International
Atomic Energy Agency; PDB originates from the CaCO3 of the rostrum of a Cretaceous belemnite, Belemnitella americana, collected in the Peedee formation of South Carolina, USA) indicating a deep-seated (mantle) origin for most of the CO2. Nevertheless, in the case of the heavier δ13C(TIDC) values, the contribution of metamorphic CO2 or the dissolution of carbonate rock levels at depth cannot be excluded. Concerning the hot waters, the lack of a positive
18O-shift should be attributed to water-rock interaction in a low temperature environment, rather than to the isotopic influence
of CO2 on the δ18O-value of the waters.
Received: 9 August 1999 · Accepted: 8 March 2000 相似文献
18.
Relation of streams, lakes, and wetlands to groundwater flow systems 总被引:14,自引:10,他引:14
Thomas C. Winter 《Hydrogeology Journal》1999,7(1):28-45
Surface-water bodies are integral parts of groundwater flow systems. Groundwater interacts with surface water in nearly all
landscapes, ranging from small streams, lakes, and wetlands in headwater areas to major river valleys and seacoasts. Although
it generally is assumed that topographically high areas are groundwater recharge areas and topographically low areas are groundwater
discharge areas, this is true primarily for regional flow systems. The superposition of local flow systems associated with
surface-water bodies on this regional framework results in complex interactions between groundwater and surface water in all
landscapes, regardless of regional topographic position. Hydrologic processes associated with the surface-water bodies themselves,
such as seasonally high surface-water levels and evaporation and transpiration of groundwater from around the perimeter of
surface-water bodies, are a major cause of the complex and seasonally dynamic groundwater flow fields associated with surface
water. These processes have been documented at research sites in glacial, dune, coastal, mantled karst, and riverine terrains.
Received, April 1998 · Revised, July 1998, August 1998 · Accepted, September 1998 相似文献
19.
Contributions of groundwater conditions to soil and water salinization 总被引:21,自引:2,他引:21
Salinization is the process whereby the concentration of dissolved salts in water and soil is increased due to natural or
human-induced processes. Water is lost through one or any combination of four main mechanisms: evaporation, evapotranspiration,
hydrolysis, and leakage between aquifers. Salinity increases from catchment divides to the valley floors and in the direction
of groundwater flow. Salinization is explained by two main chemical models developed by the authors: weathering and deposition.
These models are in agreement with the weathering and depositional geological processes that have formed soils and overburden
in the catchments. Five soil-change processes in arid and semi-arid climates are associated with waterlogging and water. In
all represented cases, groundwater is the main geological agent for transmitting, accumulating, and discharging salt. At a
small catchment scale in South and Western Australia, water is lost through evapotranspiration and hydrolysis. Saline groundwater
flows along the beds of the streams and is accumulated in paleochannels, which act as a salt repository, and finally discharges
in lakes, where most of the saline groundwater is concentrated. In the hummocky terrains of the Northern Great Plains Region,
Canada and USA, the localized recharge and discharge scenarios cause salinization to occur mainly in depressions, in conjunction
with the formation of saline soils and seepages. On a regional scale within closed basins, this process can create playas
or saline lakes. In the continental aquifers of the rift basins of Sudan, salinity increases along the groundwater flow path
and forms a saline zone at the distal end. The saline zone in each rift forms a closed ridge, which coincides with the closed
trough of the groundwater-level map. The saline body or bodies were formed by evaporation coupled with alkaline-earth carbonate
precipitation and dissolution of capillary salts.
Received, May 1998 · Revised, July 1998 · Accepted, September 1998 相似文献
20.
Groundwater pollution due to discharge of industrial effluents in Venkatapuram area, Visakhapatnam, Andhra Pradesh, India 总被引:1,自引:0,他引:1
Hindustan Polymers Limited was established in the Venkatapuram area in the northwestern part of Visakhapatnam urban agglomeration.
Untreated industrial effluent from the plant is discharged with total dissolved solids concentrations reaching up to 6500 mg/l.
The groundwater pollution was identified as early as 1981 and a hydrogeologic and water-quality database is available from
1981. The groundwater quality in the plant environs is found to be in the range of 3500–4500 mg/l. Major chemical constituents
of industrial-waste waters consist of Na, Cl, and SO4. Some characteristic parameters of the aquifer were estimated. The available hydrogeologic and hydrologic data was analyzed
to conceptualize the groundwater regime. A mathematical groundwater flow model was constructed to compute the hydraulic head
at the center of finite-difference grid. The computed head distribution and effective porosity of the formations were used
to calculate the groundwater flow velocity. The computed velocity field was ultimately used to prognose the pollutant migration
in groundwater accounting for the advection and dispersion processes in the mass transport model and for determining the time-dependent
pathlines of pollutant. Areal migration of pollutants from the source was predicted up to year 2002.
Received: 23 December 1996 · Accepted: 9 September 1997 相似文献