共查询到20条相似文献，搜索用时 24 毫秒
1.
Abdelrahman Mohamed Abdelgawad Kunio Watanabe Mebruk Mohammed Shinji Takeuchi 《Environmental Earth Sciences》2010,60(3):449-462
High levels of fluoride concentration were observed in deep groundwater of the Mizunami area in Central Japan. Fluoride occurs
mainly due to the reaction between granitic basement rock and groundwater. Granites were collected, crushed to powder, and
then allowed to react with purified water for 80 days. Water–rock interaction results showed that the major factor affecting
fluoride concentration is the residence time of the groundwater. Coexisting ions have also some contribution toward fluoride
concentration. The groundwater residence time in the Mizunami area was estimated by applying results of water–rock interaction
to correspond with field data. A regression model relating fluoride concentration, residence time, and coexisting ions was
developed. The parameters of the regression model were determined using the genetic algorithms technique. Residence time was
estimated by extrapolating experimental data to correspond with filed data. Near the recharge area, residence times in the
potential fluoride source rock varied between 1 and 2,000 years, whereas near the discharge area residence times were in excess
of tens of thousands of years. The groundwater residence time was also estimated by the groundwater particle-tracking-flow
model. The estimates of groundwater residence time based on geochemical regression model were often larger than estimates
of groundwater residence time developed by particle-tracking analysis using a groundwater flow model. There were large uncertainties—on
the order of 10–10,000 years—in the estimates based on geochemical data. 相似文献
2.
Zhou Haiyan Zhou Xun Chai Rui Yu Lan Liu Chunhui Li Liangping 《Environmental Geology》2008,53(7):1483-1489
Thermal groundwater occurs in bedrock aquifers consisting of the dolomite of the Wumishan Group of the Jixianin System and
the Cambrian carbonate in the Xiaotangshan geothermal field near the northern margin of the North China Plain, China. The
hot water in the geothermal field of basin-type discharges partly in the form of the Xiaotangshan hot spring under natural
conditions. The hot water has TDS of less than 600 mg/L and is of Na·Ca-HCO3 type. The geothermal water receives recharge from precipitation in the mountain area with elevation of about 500 m above
sea level to the north of the spring. Thermal groundwater flows slowly south and southeast through a deep circulation with
a residence time of 224 years estimated with the Ra–Rn method. The Xiaotangshan hot spring dried up in the middle of the 1980s
owing to the increasing withdrawal of the hot water in the geothermal field in the past decades. The water level of the geothermal
system still falls continually at an annual average rate of about 2 m, although water temperature changes very little, indicating
that the recharge of such a geothermal system of basin-type is limited. Over-exploitation has a dramatic impact on the geothermal
system, and reduction in exploitation and reinjection are required for the sustainable usage of the hot water. 相似文献
3.
The supraregional GIS-supported stochastical model, WEKU, for the determination of groundwater residence times in the upper
aquifers of large groundwater provinces is presented. Using a two-dimensional analytical model of groundwater flow, groundwater
residence times are determined within two extreme cases. In the first case, maximal groundwater residence times are calculated,
representing the part of groundwater, that is drained by the main surface water of a groundwater catchment area. In the second
case, minimal groundwater residence times for drainage into the nearest surface water are determined. Using explicit distribution
functions of the input parameters, mean values as well as potential ranges of variations of the groundwater residence times
are derived. The WEKU model has been used for the determination of groundwater residence times throughout Germany. The model
results – mean values and deviations of the groundwater velocity and the maximal and minimal groundwater residence times in
the upper aquifers – are presented by general maps and discussed in detail. It is shown that the groundwater residence times
in the upper aquifer vary regionally, differentiated between less than 1 year and more than 2000 years. Using this information,
the time scales can be specified, until measures to remediate polluted groundwater resources may lead to a substantial groundwater
quality improvement in the different groundwater provinces of Germany. With respect to its supraregional scale of application,
the WEKU model may serve as a useful tool for the supraregional groundwater management on a state, federal or international
level.
Received: 15 August 1995 · Accepted: 15 October 1995 相似文献
4.
A. Herch 《Environmental Geology》2000,39(5):437-447
The Aachen hot springs flow out from Upper Devonian limestones at the Variscan thrust front of the Rhenish Massif. Hydrogeochemical
analyses were used to determine the origin of the water and show that sodium, chloride, and sulfate originate from dissolving
evaporites that are influenced by meteoric groundwater. The circulation depths of the Aachen thermal water is estimated to
be >3500 m using SiO2–geothermometry and the regional geothermal gradient of about 30 °C/km. The deep circulation in Paleozoic sandstones, siltstones
and shales and a considerable residence time allow rock water reactions which explain the concentrations of Ba, Sr, F and
Si. While the thermal water rises into Upper Devonian limestones carbonates are dissolved. Cooler fresh water from the vicinity
contributes to the thermal aquifer depending on the pressure head of the springs. Sulfate reduction coupled with methane oxidation
can be observed as soon as the water temperature is below 65 °C.
Received: 21 September 1998 · Accepted: 19 May 1999 相似文献
5.
北京延庆县松山温泉的特征与成因 总被引：1，自引：0，他引：1
松山温泉位于北京市延庆县松山森林公园内,附近为燕山期花岗岩,岩体裂隙较发育。在该温泉附近施工的2个钻孔自流热水。温泉及其附近自流孔热水水温为32~42 ℃,主要阳离子为Na+、K+和Ca2+,主要阴离子为SO42-、HCO-3和Cl-,水化学类型为SO4-Na型;热水矿化度为0.548~0.566 g/L,pH值为9.14~9.21,H2SiO3含量为87.1~97.1 mg/L,F-含量为19.0~20.8 mg/L。氢、氧同位素资料表明,研究区地下热水来源于大气降水;估算的补给高程为1 256~1 351 m,补给区温度为4.4~8.8 ℃,热水年龄为14.19~48.95 a,地下热储温度为114~119 ℃,热水循环深度为2 236~2 274 m。松山温泉为花岗岩中地下水在山区获得大气降水入渗补给后,在经历深循环过程中获得深部热流加热后上升在山坡上出露形成的温泉。 相似文献
6.
Environmental isotopic and hydrochemical study of groundwater in the Ejina Basin,northwest China 总被引：5，自引：0，他引：5
The study investigates the groundwater evolution and its residence time in the Ejina Basin, northwest China according to isotope
and hydrochemical analyses results. The groundwater chemistry is mainly controlled by the dissolution of halite, Glauber’s
salt, gypsum, dolomite and calcite, also influenced by other processes such as evaporation, ion exchange, and deposition.
Based on tritium content in atmospheric precipitation and by adopting a model with exponential time distribution function,
the mean residence time of the unconfined aquifer groundwater with fairly high tritium activities (21–49 TU) is evaluated.
The results show that these groundwaters have low residence time (5–120 years) and are renewable. In contrast, the deep confined
groundwaters are tritium-free and radiocarbon values range from 18.3 to 26.7 pmc. According to the most commonly used 14C correction models, the radiocarbon groundwater ages were calculated which yield ages of approximately 4,087–9,364 years
BP. Isotopic signatures indicate formation of deep confined groundwaters in a colder and wetter climate during the late Pleistocene
and Holocene. It is suggested that long-term, rational water usage guide should be set up for the Heihe River Basin as a whole
to permit a considerable discharge to the Ejina Basin. 相似文献
7.
浅析开采条件下地下热水资源的演变 总被引：16，自引：1，他引：16
地下热水的分布可以分为埋藏型(或盆地型)和出露型(或温泉型).埋藏型分布于沉积盆地深处,热储层规模大,有较大的储存资源,但补给资源极为有限或缺乏,开采地下热水主要是消耗储存资源,可导致热水系统水位持续下降.出露型多见于山区,地下热水以温泉的方式出露地表,其储存资源和补给资源均有限,在温泉附近开采热水可导致温泉流量减小直至干涸,热水系统水位、水温也会持续下降.在某些特定条件下在温泉附近打成的自流孔可使地下热水资源量有所增加.温泉的自封闭作用可使其流量减少. 相似文献
8.
青海贵德县扎仓温泉特征及其开发利用 总被引：1，自引：1，他引：0
扎仓温泉位于青海省贵德县扎仓寺村,其开发利用至今已有600多年的历史。温泉出露于断裂带交汇部位,地下热水矿化度为1 310~1 390 mg/L, 水化学类型属于SO4·Cl-Na型。研究结果表明,温泉的补给来源为大气降水,温泉水年龄约165 a。利用SiO2温标法计算出热储温度为136 ℃,估算热水循环深度为1 385 m。温泉的天然放热量大于1.23×1014J/a,扎仓沟地区的地热资源量达2.07×1014J以上。热水宜直接用于供暖、洗浴、温室种植和养殖等。该地热田深部尚有地热能潜力。 相似文献
9.
In the periods 1980–1986 and 1990–2007 many boreholes were sunk during hydrogeological investigations in the center of the
Karlovy Vary (Carlsbad) hot spring system. The extent and the depths reached were the greatest in the history of the geological
investigation of the discharge area of the thermal system. The results of the drilling program enabled a detailed study of
the rocks, groundwater and spring sedimentation in the area as well as the preparation of new proposals for changes in the
spring-protection zones. The spring sedimentation consists of world-renowned hot spring travertine, with a wide range of morphological
varieties of different origins and of different ages. The oldest U-series age data (230 ± 14 ka BP) have been obtained for
travertine relicts located 22 m above the present-day bottom of the narrow valley of the Teplá River. Five other travertine
deposits, partly overlapping in space and time were identified on the bottom and slopes of the valley. They were formed by
gradual growth, by river erosion and since the fourteenth century by human activities. 相似文献
10.
Radon measurements in soil and groundwater (springs, thermal springs and handpumps) were made in a variety of lithological
units including major thrusts between Mandi and Manali in Himachal Himalaya. Analysis of radon data in light of lithological
controls and influence of deep-seated thrusts has been made to elucidate the causative factors for anomalous emanation of
radon. The lithological types include banded gneisses, schists, quartzite, granite, phyllites, volcanics and mylonites. The
low-grade metasedimentries of Shali and Dharamsala generally show low and narrow range of radon concentration in water (5.6–13.4 Bq/l)
as well as in soil (1.8–3.2 kBq/m3) except for the samples related to thrusts. On the other hand, sheared and deformed rocks of Chail and Jutogh show moderate
radon content (average 5.03 kBq/m3, range 2.9–11.1 kBq/m3) in soil. However, the groundwater radon concentration shows wide variation in different types of sources (2.1–80.8 Bq/l).
The quartzite and volcanic rocks of Rampur formation in this area present as a window separated by Chail thrust. Radon emanations
on these rock types are relatively high (6.3–68.1 Bq/l in water and 5.5–15.9 kBq/m3 in soil) and are exceptionally high in samples that are related to uranium mineralization, deep-seated thrusts and hot springs
(13.5–653.5 Bq/l). It is generally observed that anomalous high radon content is associated with mineralization, deeper source
and tectonic discontinuities. Whereas it is obvious that subsurface radioactive mineralization would facilitate enhanced radon
production, however, thrust plains provide easy pathways for escape of gases from the deeper sources. Shallow and deep sources
of the groundwater have contrasting radon content particularly in the deformed and metamorphosed rocks of Jutogh and Chail.
Shallow groundwater sources, mainly handpumps, have lower radon concentration due to limited superficial water circulation,
whereas deeper sources, mainly perennial springs, show higher radon content because of larger opportunity for water–rock interaction. 相似文献
11.
A strong geochemical gradient was observed in the thick overburden aquifer of the Asa drainage basin. Different types of
groundwater occur at different (downslope) locations and groundwater table depths. The following sequence was noticed with
increasing distance downslope or with increasing groundwater table depth:
1. Ca–Mg–HCO3 water at about 390-m groundwater table elevations or upslope locations.
2. Ca–Mg–HCO3–Cl water at middle-slope locations or groundwater table elevations of about 350 m above sea level;
3. Ca–Mg–SO4–Cl water at downslope locations or groundwater table elevations of about 300 m above sea level.
In this basin, changes in the type of water are expected at about every 40–50 m depth from the surface. Statistical analysis
via the determination of the correlation coefficient (r) and regression analysis shows that about 80–99% of the variation in groundwater chemistry is accounted for by the topography,
using the model presented in this paper. The rate of change in the sequence will depend on the permeability of the aquifer,
which determines the rate of groundwater flow and the residence time, and the nature of recharge.
Received: 4 February 1997 · Accepted: 22 July 1997 相似文献
12.
Hydrogeochemical and isotopic composition of a low-temperature geothermal source in northwest Turkey: case study of Kirkgecit geothermal area 总被引：2，自引：1，他引：1
Chemical and isotopic compositions of three hot springs and one cold spring in the Kirkgecit geothermal field, located 15 km
southwest of Canakkale-Biga in the northwest of Turkey, were monitored five times during 2005 and 2007. The physico-chemical
characteristics of the hot springs are average discharge 3–3.5 L/s, surface temperature 45–52°C, pH 8.9–9.3, and electrical
conductivity (EC) 620–698 μS/cm. The cold spring has a temperature of 12–13°C, pH 7.5–8.3, and EC 653–675 μS/cm. The hot waters
are Na-SO4 type, whereas the cold water is Ca-HCO3 type. Chemical geothermometers suggest that the reservoir temperature is around 80–100°C. The isotopic data (oxygen-18, deuterium
and tritium) indicate that the thermal waters are formed by local recharge and deep circulation of meteoric waters. 相似文献
13.
Comparing groundwater recharge and base flow in the Bukmoongol small-forested watershed,Korea 总被引：1，自引：0，他引：1
E. A. Combalicer S. H. Lee S. Ahn D. Y. Kim S. Im 《Journal of Earth System Science》2008,117(5):553-566
Groundwater recharge and base flow using different investigated methods are simulated in the 15-ha Bukmoongol small-forested
watershed located at the southern part of Korea. The WHAT system, PART, RORA, PULSE, BFI, and RAP software are used to estimate
groundwater recharge or base flow and base flow index from the measured streamflow. Results show that about 15–31 per cent
of annual rainfall might be contributed for base flow. The watershed groundwater recharge proportions are computed to about
10–21 per cent during the wet period and 23–32 per cent for the remainder periods. Mean annual base flow indices vary from
0.25 to 0.76 estimated using different methods. However, the study found out that all methods were significantly correlated
with each other. The similarity of various methods is expressed as a weighted relationship provided by the matrix product
from the principal component analysis. Overall, the BFI and WHAT software appeared consistent in estimating recharge or base
flow, and base flow index under Korea’s conditions. The case study recommends the application of different models to other
watersheds as well as in low-lying areas where most observation groundwater wells are located with available streamflow data. 相似文献
14.
河北丰宁县的洪汤寺温泉出露于燕山期第四期的钾长花岗岩中,是由地下水接受大气降水入渗补给后向深处循环获得热量上升到地表后形成的。其TDS小于400mg/L,主要阳离子为Na+,主要阴离子为SO42-和HCO 3-,水化学类型属于SO4.HCO3—Na型水,特点为F-、偏硅酸以及氡含量高,分别为17.5mg/L、75.7mg/L和131.1 Bq/L。热水的同位素资料表明,洪汤寺温泉热水起源于大气降水,用氚法估算出的年龄在22a以上。利用地热温标估算地下热储温度范围为79～109℃。钻孔揭露后自流量增大,达11.6 L/s。 相似文献
15.
James H. Wiersma Ronald D. Stieglitz Dewayne L. Cecil Glenn M. Metzler 《Environmental Geology》1986,8(1-2):99-104
Door County, Wisconsin, is a region of karst topography underlain by Silurian dolomite bedrock. Numerous sinkholes intercept
much of the surface runoff and act as sites for direct groundwater recharge. The clay-rich and impermeable Upper Ordovician
Maquoketa formation separates the dolomite aquifer from the deeper aquifers and appears to be a factor in groundwater circulation
and karst formation Thin glacial drift and Quaternary materials overlie the dolomite and are hydrologically connected with
it
The interactions of surface and groundwater, and the role of solution features in water interchange were studied in a small
drainage basin. This basin contains several large sinkholes and a nearby spring complex Mapping identified many additional
sinks and swallets in surface drainage routes Water flowing into two sinks was traced and found to have a residence time of
several hours. Water flowing into sinkholes and from the spring was sampled to identify the quality and seasonal trends in
composition of the shallow groundwater Water quality parameters monitored include magnesium, sodium, potassium, chloride,
phosphorous, nitrate and ammonia, nitrogen, alkalinity, pH, turbidity, and specific conductance. Nitrate levels were found
to increase 5 to 6 times during periods when there was zero input through sinkhole recharge sites. Nitrate levels approached
the 10 mg/l NO3
−-N limit set by the U.S. Public Health Service for drinking water
In this basin sandy soils are most susceptible to sink development, whereas clay-rich soils have a lesser number of sinks.
It appears, however, that a network of bedrock solution features exists under all soils The loss of soil into sinkholes has
impacted groundwater quality and reduced agricultural productivity through a reduction in tillable acreage and water retention
capacity. 相似文献
16.
Changes in hydraulic heads with space and time and evolution of the location of fresh water–salt water interface are important
for groundwater development in coastal aquifers. Measurements of piezometric heads at 11 well clusters consisting of three
piezometric wells of different depths with a 5-day interval for 15 months show that the piezometric heads at nearly all the
wells near the northwestern coast in Beihai decrease with increasing depth and increase with increasing distance from the
coast. Changes in piezometric heads at the wells during the measurement period were caused by seasonal precipitation and induced
by the tide. The depth of the sharp interface between fresh water–salt water can be estimated based on measurements of piezometric
heads at a piezometric well tapping at a point in the salt water zone below the interface and measurements of the water table
at the same well. The calculations of the interface for well H5 range from 40 to 80 m below sea level in the measurement period,
which are believed to be more reasonable than those estimated with the Ghyben–Herzberg relation.
An erratum to this article can be found at 相似文献
17.
The distribution of several minor and trace elements mainly in fresh (dominating TDS 160–400 mg/l) groundwater of Latvia have
been investigated by the Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) technique. An evaluation of results of about
700 analyses leads to the conclusion that concentrations of these elements is influenced by: pH–Eh conditions, groundwater
residence time and diffuse contamination, whereas the role of water-bearing sediments is of secondary importance. Most trace
elements are characterised by low mobility under alkaline and reducing conditions; concentrations in confined aquifers are
much smaller than the Maximum Permissible Values for drinking water. The strongest anomalies of REE, Al and P were found in
shallow groundwater around the former agrochemical storehouses. 相似文献
18.
为研究四川省康定市二道桥地区地下热水稳定同位素特征和热储温度,对二道桥地区5个温泉(井)即二道桥温泉(SC107、SC107-2)、康巴人家温泉(SC107-3)、自流热水井(SC107-4)、自喷热水井(SC107-5)进行调查和分析。研究区温泉的分布及出露主要受雅拉沟断裂和雅拉河谷控制。温泉水温33.2~46 ℃,为中低温温泉,pH为6~6.5。水样的氢氧稳定同位素特征表明研究区地下热水的补给来源为大气降水。利用氢氧稳定同位素高程效应及温度效应估算区内地下热水补给区高程为3 000~4 500 m,补给区温度为-3.5~-0.3 ℃,表明地下热水有一部分补给源自附近山区的冰雪融水。Na-K-Mg三角图显示研究区热水均为未成熟水,不宜用阳离子地热温标计算热储温度。应用SiO2地热温标、多矿物饱和指数法以及用固定铝方法对部分温泉多矿物平衡图进行修正,得出研究区地下热水的热储温度为65~75 ℃。研究区温泉在东部跑马山以及西部农戈山附近接受大气降水补给,降水沿着大雪山—农戈山断裂和跑马山断裂下渗,地下水经历深循环,在此过程中获得大地热流加热,最终在雅拉河谷雅拉沟断裂附近出露成泉。 相似文献
19.
Kelly Addy Arthur Gold Barbara Nowicki James McKenna Mark Stolt Peter Groffman 《Estuaries and Coasts》2005,28(6):896-908
Coastal waters are severely threatened by nitrogen (N) loading from direct groundwater discharge. The subterranean estuary,
the mixing zone of fresh groundwater and sea water in a coastal aquifer, has a high potential to remove substantial N. A network
of piezometers was used to characterize the denitrification capacity and groundwater flow paths in the subterranean estuary
below a Rhode Island fringing salt marsh.15N-enriched nitrate was injected into the subterranean estuary (in situ push-pull method) to evaluate the denitrification capacity
of the saturated zone at multiple depths (125–300 cm) below different zones (upland-marsh transition zone, high marsh, and
low marsh). From the upland to low marsh, the water table became shallower, groundwater dissolved oxygen decreased, and groundwater
pH, soil organic carbon, and total root biomass increased. As groundwater approached the high and low marsh, the hydraulic
gradient increased and deep groundwater upwelled. In the warm season (groundwater temperature >12 °C), elevated groundwater
denitrification capacity within each zone was observed. The warm season low marsh groundwater denitrification capacity was
significantly higher than all other zones and depths. In the cool season (groundwater temperature <10.5 °C), elevated groundwater
denitrification capacity was only found in the low marsh. Additions of dissolved organic carbon did not alter groundwater
denitrification capacity suggesting that an alternative electron donor, possibly transported by tidal inundation from the
root zone, may be limiting. Combining flow paths with denitrification capacity and saturated porewater residence time, we
estimated that as much as 29–60 mg N could be removed from 11 of water flowing through the subterranean estuary below the
low marsh, arguing for the significance of subterranean estuaries in annual watershed scale N budgets. 相似文献
20.
Recharge rate estimation in the Mountain karst aquifer system of Figeh spring, Syria 总被引：3，自引：1，他引：2
A. Al-Charideh 《Environmental Earth Sciences》2012,65(4):1169-1178
Figeh watershed spring is one of the important groundwater aquifer, which is considered a major source for drinking waters
of Damascus city and countryside. The origin identification and recharge estimates of groundwater are significant components
of sustainable groundwater development in this Mountain karst aquifer of Figeh spring. During the period 2001–2009, monthly
groundwater and precipitation samples were taken and the isotopic compositions of δ18O, δ2H, and chloride contents were analyzed to identify groundwater origins and to estimate recharge rates. The δ18O, δ2H of the groundwater show that the groundwater recharge is of meteoric origin. The chloride mass balance (CMB) method was
used to quantify recharge rates of groundwater in the Mountain karst aquifer of Figeh spring. The recharge rate varies from
192 to 826 mm/year, which corresponds to 43 and 67% of the total annual rainfall. Recharge rates estimated by CMB were compared
with values obtained from other methods and were found to be in good agreement. This study can be used to develop effective
programs for groundwater management and development. 相似文献