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1.
The principles of hydrogeological zoning of the territory of Russia by the conditions of formation and the distribution of the natural resources of fresh groundwater are discussed. The delineation of the first- and second-order regions is shown to be based on the principles of general hydrogeologic zoning, whereas that of the third and fourth orders is shown to be based on the principles of special hydrogeologic zoning, which can account for the specific structural features of the hydrogeologic section of the zone of intense water exchange, different types of water-bearing rocks, the structure of the unsaturated zone, and, in a number of cases, the climatic and landscape features of the area. 相似文献
2.
The effect of climate on the present-day formation conditions of the regimes of annual and base runoff in Eastern Siberia
rivers and changes in those regimes are studied. The significant climate warming in Eastern Siberia in recent decades is shown
to be accompanied by not only an increase in air temperature and some increase in precipitation, but also by a considerable
changes in the annual and seasonal values of river and groundwater runoff. Hydrometeorological data are used to analyze variations
in the mean annual and mean base runoff over the entire observation period divided into subperiods of 1940–1969 and 1970–2005.
Plots, diagrams, and tables are constructed for the most representative gauges. The zoning of the territory by the runoff
formation conditions was carried out and new estimates were derived for total water resources and natural groundwater resources
for 1970–2005 with the construction of maps in ArcMap program. 相似文献
3.
A detailed hydrogeological zoning of the central part of the Minusinsk artesian basin is performed. Local basins confined to smaller plicated structures, as well as hydrogeological massifs of local scale, are recognized within large block structures. Direction of subsurface streams and their role in the formation of groundwater resources and composition are discussed. Forecast resources of fresh groundwater are estimated for every recognized structure. 相似文献
4.
Principles of regional estimation of infiltration groundwater recharge based on geohydrological models 总被引：1，自引：0，他引：1
Principles of estimation of infiltration groundwater recharge based on modeling the formation of water balance on the land
surface and in the vadose zone are considered. The application of such models for regional discharge evaluation involves zoning
of the territory by a set of meteorological, landscape, geological, soil, and hydrogeological factors. The reliability of
the obtained estimates of water balance components, including infiltration recharge, should be assessed by correlating the
calculated and measured river runoff characteristics for drainage basins within which the water-bearing section in the zone
of active water exchange is completely drained. The application of such approach is illustrated by calculations for southwestern
Moscow Artesian Basin. 相似文献
5.
The natural-climatic causes of changes in river runoff and seasonal recharge of groundwater in Don basin are considered. Joint
analysis is made of changes in the statistical characteristics of the series of air temperature and precipitation, mean annual
and dry-season-averaged runoff for both the entire observation period and of periods 1940–1969 and 1970–2000 with comparable
durations. The presence of statistically reliable ascending trends in air temperature, precipitation, and dry-season (groundwater)
runoff for period 1970–2005 is demonstrated. Climatic changes in Don basin also have their effect on the formation of extremely
low water in small and medium rivers, including cases of zero runoff. Zoning of the territory by runoff formation conditions
is carried out, and new estimates of natural groundwater resources in Don basin for period 1970–2000 are constructed. Appropriate
maps are compiled. 相似文献
6.
Urban subsurface space is considered to be a dynamic multicomponent system, which includes sandy-clayey soils, groundwater in different state, microbiota, gases, and underground facilities (either as foundations or as surrounding walls), or engineering structures (tunnels of different purpose, hazardous industrial-waste storages, etc.). Special attention is paid to the significance of hydrogeological studies, primarily, to the influence of hydrodynamic and physicochemical conditions and aquifer chemistry on soils, stress and strain state of the stratum, deformation of structures, and the formation of corrosiveness of subsurface medium. The main factors that govern groundwater composition within zones with different contamination level in megacity territory are analyzed. Results of studying the effect of various aquifers on the conditions of construction and operation of above-ground and subsurface structures are presented. Recommendations for assessing the hydrogeological conditions as a part of geotechnical survey are given. 相似文献
7.
The processes of formation and distribution of the resources of fresh groundwater and surface water in the territory of Crimea Peninsula are considered. Water availability in the natural–historic and administrative regions of the republic is characterized. The proportions between different categories of groundwater resources are shown with their role in water supply to Crimea taken into account. The presentday development of groundwater resources is analyzed and the possible increase in water consumption meeting geoecological requirements is substantiated. 相似文献
8.
Effect of climate changes on groundwater 总被引：1，自引：0，他引：1
V. S. Kovalevskii 《Water Resources》2007,34(2):140-152
Predictive estimates of anticipated changes in groundwater resources in the territory of Russia as applied to global climate warming by 1, 2, and 3–4°C at different scenarios of changes in the regional distribution of atmospheric precipitation are given. Potential environmental and socio-economic consequences of changes in hydrogeological conditions are considered. 相似文献
9.
Using chlorofluorocarbons (CFCs) and tritium to improve conceptual model of groundwater flow in the South Coast Aquifers of Laizhou Bay,China 总被引：1，自引：0，他引：1
The southern coastal plain of Laizhou Bay, which is the area most seriously affected by salt water intrusion in north China, is a large alluvial depression, which represents one of the most important hydrogeological units in the coastal region of northern China. Chlorofluorocarbons (CFCs, including CFC‐11, CFC‐12 and CFC‐113) and tritium were used together for dating groundwater up to 50 years old in the study area. There are two cones of depression, caused by intensive over‐exploitation of fresh groundwater in the south and brine water in the north. The assigned CFC apparent ages for shallow groundwater range from 8 a to >50 a. A binary mixing model based on CFC‐113 and CFC‐12 concentrations in groundwater was used to estimate fractions of young and pre‐modern water in shallow aquifers and to identify groundwater mixing processes during saltwater intrusion. Discordance between concentrations of different CFC compounds indicate that shallow groundwater around the Changyi cone of depression is vulnerable to contamination. Pumping activities, CFC contamination, mixing and/or a large unsaturated zone thickness (e.g. >20 m) may be reasons for some groundwater containing CFCs without tritium. Saline intrusion mainly occurs because of large head gradients between fresh groundwater in the south and saline water bodies in the north, forming a wedge of saline water below/within fresh aquifer layers. Both CFC and tritium dates indicate that the majority of the saline water is from >50 a, with little or no modern seawater component. Based on the distribution of CFC apparent ages, tritium contents plus chemical and physical data, a conceptual model of groundwater flow along the investigated Changyi‐Xiaying transect has been developed to describe the hydrogeological processes. Three regimes are identified from south to north: (i) fresh groundwater zone, with a mixing fraction of 0.80–0.65 ‘young’ water calculated with the CFC binary mixing model (groundwater ages <34 a) and 1.9–7.8TU of tritium; (ii) mixing zone characterized by a mixing fraction of 0.05–0.65 young groundwater (ages of 23–44 a), accompanied by local vertical recharge and upward leakage of older groundwater; and (iii) salt water zone, mostly comprising waters with ages beyond the dating range of both CFCs and tritium. Some shallow groundwater in the north of the Changyi groundwater depression belongs to the >50a water group (iii), indicating slow velocity of groundwater circulation and possible drawing in of saline or deep groundwater that is tracer‐free. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
10.
Kuskovskii V. S. Kashevarov A. A. Rasskazov N. M. Rybakova S. T. 《Water Resources》2001,28(3):257-265
The hydrogeological conditions of the Kuznetsk Coal Basin (Kuzbass) region are considered. Estimates of the safe yield and natural groundwater resources for this region are given. Better-quality groundwater are shown to be available for public water supply to some localities in Kuzbass. The applicability of mathematical modeling to forecasting the changes in the hydrogeological conditions caused by flooding of unprofitable mines is discussed. 相似文献
11.
Caroline C. Mather David J. Nash Shawan Dogramaci Pauline F. Grierson Grzegorz Skrzypek 《地球表面变化过程与地形》2019,44(14):2752-2770
Groundwater dolocretes may exert an important geomorphic control on landscape evolution within sub-humid to arid regions. However, the geomorphic and hydrogeological settings of dolocrete remain poorly described. The hydrochemical conditions of dolomite precipitation in groundwater environments are also not well known. Classic models of dolocrete formation explain dolomite precipitation from highly evolved groundwaters at the terminus of major drainage but do not explain dolocrete distributed in regionally elevated landscapes, upgradient of major drainage. This study investigated the mineralogy, micromorphology and stable carbon and oxygen isotope compositions of three dolocrete profiles within a regionally elevated sub-basin of the Hamersley Ranges in the Pilbara region of northwest Australia. We sought to establish the environmental and hydrochemical conditions and present a model for dolocrete formation. We found that dolocrete formed within zones of emerging groundwater under saline-evaporitic conditions within internally draining sub-basins, most likely during the Late Miocene and Pliocene. Saline-evaporitic conditions were indicated by: (i) the mineralogy, dominated by dolomite, palygorskite and smectite; (ii) desiccation features and the presence of phreatic and vadose cements, indicative of a shallow fluctuating water table, and; (iii) dolomite δ18O values (median = –5.88 ‰). Dolomite precipitation was promoted by evaporation and carbon dioxide degassing from shallow magnesium (Mg)-rich groundwater. These factors appear to have been the major drivers of dolocrete development without a requirement for significant down-dip hydrochemical modification. Primary dolomite precipitation was possible due to the presence of microbial extracellular polymeric substances (EPS). EPS provided negatively charged nucleation sites, which bound Mg2+, overcoming kinetic effects. High microbial activity within groundwater systems suggest these processes may be important for dolocrete formation worldwide and that groundwater dolocretes may be more pervasive in landscapes than currently recognized. © 2019 John Wiley & Sons, Ltd. © 2019 John Wiley & Sons, Ltd. 相似文献
12.
Aquifer storage and recovery (ASR) is a valuable tool for managing variations in the supply and demand of freshwater, but system performance is highly dependent upon system-specific hydrogeological conditions including the salinity of the storage-zone native groundwater. ASR systems using storage zones containing saline (>10,000 mg/L of total dissolved solids) groundwater tend to have relatively low recovery efficiencies (REs). However, the drawbacks of low REs may be offset by lesser treatment requirements and may be of secondary importance where the stored water (e.g., excess reclaimed, surface, and storm waters) would otherwise go to waste and pose disposal costs. Density-dependent, solute-transport modeling results demonstrate that the RE of ASR systems using a saline storage zone is most strongly controlled by parameters controlling free convection (e.g., horizontal hydraulic conductivity) and mixing of recharged and native groundwater (e.g., dispersivity and aquifer heterogeneity). Preferred storage zone conditions are moderate hydraulic conductivities (5 to 20 m/d), low degrees of aquifer heterogeneity, and primary porosity-dominated siliclastic and limestones lithologies with effective porosities greater than 5%. Where hydrogeological conditions are less favorable, operational options are available to improve RE, such as preferential recovery from the top of the storage zone. Injection of large volumes of excess water currently not needed into saline aquifers could create valuable water resources that could be tapped in the future during times of greater need. 相似文献
13.
Dramatic decreases in groundwater quality have raised widespread concerns about water supplies and ecological crises in China. In this study, hydrochemistry, stable isotopes, and graphical and multivariate statistical methods are integrated to identify hydrogeochemical processes controlling groundwater quality in the Yuncheng Basin, China. Our results show that groundwater with 21 variables (pH, temperature-T, total dissolved solid, major-trace elements, and stable isotopes) is chemically classified into three distinct clusters: fresh water [C1], brackish-saline water [C2], and saline water [C3]. Groundwater salinization is identified as the prime process in controlling groundwater quality for shallow groundwater and deep groundwater in the lowland areas. Large-scale As, F, or B contaminations found in groundwater are closely related to groundwater salinization, agricultural activity, and the exploration of geothermal water in the area. With respect to the risk of contamination, groundwater in the basin is spatially divided into the following: shallow groundwater with a high risk located in the north side of the Salt Lake, shallow groundwater with a moderate risk, and deep groundwater with a low to moderate risk. Nationally, the increasing demand on groundwater is threatened by a range of environmental and health pressures, including salinization and contaminations of nitrate, As, F, or B. Our study indicates that natural water-rock interactions and hydrogeological conditions are significant factors controlling these contaminations. Systematic management and regulation of existing groundwater resources are required to prevent further deterioration of groundwater resources. Policies should be made and implemented to ensure “green” exploitation of geothermal water. 相似文献
14.
A two-dimensional finite element model for density dependent groundwater flow was calibrated to simulate sea water intrusion in Nauru Island in the Central Pacific Ocean. Nauru Island occupies an area of 22 km2 and supports a population of 8500. The island has been mined for its phosphate deposits and current reserves indicate that the mine has about eight years life remaining. The water supply of the island is about one third dependent on imported water which is also used as ballast on the phosphate ships. Imported water will not be available in the future, and a hydrogeological investigation shows that the island is underlain by a fresh water layer, less than 5 m thick. The freshwater layer overlies a thick transition zone of brackish water which in turn overlies sea water. Simulation of several management options shows that it is possible to substitute current importation of fresh water by careful extraction from the groundwater resources of the island. 相似文献
15.
Groundwater is the most important and valuable natural resources especially in coastal urban environment where surface water is insufficient to satisfy the water requirement. Puri city is located on the east coast of India where groundwater is the only source available to meet city water supply. As the city is situated on the sandy aquifer, quality of groundwater is deteriorating because of anthropogenic activities, lack of sewerage system, etc. The objective of the study was to assess the groundwater fluctuation during post‐monsoon and summer with respect to hydrogeological conditions, topography, and groundwater consumption pattern of the city. For this assessment and analysis, Geographic Information System (GIS) was used to visualize topography of the area through digital elevation model (DEM) and distribution of groundwater contours spatially and temporally. The probable areas prone to contamination were identified based on aquifer property and depths to water table below ground. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
16.
Sustainable use of groundwater in the hydrothermal area of Viterbo (Central Italy) was analyzed. In this area, multipurposes utilization of groundwater coexists: several thermal springs and wells supply spas and public pools, cold and fresh water is used for irrigation and drinking-water. Starting from theoretical concepts, a management plan has been developed to ensure groundwater sustainability in response to the increased demand of withdrawal from thermal wells, by integrating previous hydrogeological studies, new investigations and a new finite-difference model. The most stringent constraints considered are: to maintain the quality of thermal and fresh waters, to limit the effects on the hydraulic equilibrium existing between overlapping aquifers, to ensure a significant flow to the natural thermal springs and the quality and flow rate of the spring used for drinking purposes. The practical approach included identification of the maximum pumping rate from the wells of the spas, analysis of the response time of the system under development and drafting of a safeguard and monitoring plan. The case examined takes into account the complexity of the task in defining practical measures for groundwater management on the basis of theoretical concepts of its sustainable use. A participative approach among the different water decision-makers and adaptive management in the use of groundwater resources with different quality represent the key points to overcome conflicts between different users, with the awareness of the ineludible uncertainties of the hydrogeological model. 相似文献
17.
The effect of meteorological, landscape, geological-pedological, and hydrogeological factors on the formation of total water
balance and infiltration recharge of groundwater. The results of analysis of calculated mean annual and within-year values
of water balance elements on land surface and in the vadose zone were used to identify some regularities, governing the resulting
input of moisture to groundwater table at different depth of its occurrence (infiltration). 相似文献
18.
Nelson Attandoh Sandow Mark Yidana Aliou Abdul‐Samed Patrick Asamoah Sakyi Bruce Banoeng‐Yakubo Prosper M. Nude 《水文研究》2013,27(11):1664-1676
Groundwater resources play a pivotal role in the rural water delivery system in Ghana. The hydrogeological system of Middle Voltaian terrain was simulated using available data on hydraulic heads and boundary conditions. The objective was to characterize the general groundwater flow pattern and provide local estimates of the distribution of hydraulic conductivity and recharge fields. The results suggest a predominant NE–SW flow direction, which ties in with the general regional structural trend and indicates that the hydrogeological conditions of the rocks are controlled by structural entities created in the wake of fracturing and/or weathering of the rocks whose primary permeabilities are considerably reduced because of high compaction and low‐grade metamorphism. Calibrated hydraulic conductivities range between 1.90 and 10.81 m/d. The spatial distribution appears to reflect the intensity of fracturing and/or weathering of the rock and the proportion of the clay fraction of the weathered zone. Vertical groundwater recharge has been estimated to range between 0.3% and 4.1% of the annual rainfall. This recharge rate is quite low and reflects the imperviousness of the thick overburden because of high clay content in some places and high compaction in others. Despite this apparently low recharge rate, groundwater resources potential in the area appear to be high, and increased abstraction from existing abstraction wells by up to 50% does not appear to register significant effects on groundwater budgets at the simulated recharge rates. This suggests that the well yields are much lower than the potential of the aquifer system. The apparently low yields might be associated with poor well development and the choice of inappropriate well completion materials. This study recommends a monitoring system to be developed for a much more regional groundwater flow simulation under transient conditions. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
19.
Hydraulic subsurface measurements and hydrodynamic modelling as indicators for groundwater flow systems in the Rotondo granite,Central Alps (Switzerland) 
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下载免费PDF全文 Regional groundwater flow in high mountainous terrain is governed by a multitude of factors such as geology, topography, recharge conditions, structural elements such as fracturation and regional fault zones as well as man‐made underground structures. By means of a numerical groundwater flow model, we consider the impact of deep underground tunnels and of an idealized major fault zone on the groundwater flow systems within the fractured Rotondo granite. The position of the free groundwater table as response to the above subsurface structures and, in particular, with regard to the influence of spatial distributed groundwater recharge rates is addressed. The model results show significant unsaturated zones below the mountain ridges in the study area with a thickness of up to several hundred metres. The subsurface galleries are shown to have a strong effect on the head distribution in the model domain, causing locally a reversal of natural head gradients. With respect to the position of the catchment areas to the tunnel and the corresponding type of recharge source for the tunnel inflows (i.e. glaciers or recent precipitation), as well as water table elevation, the influence of spatial distributed recharge rates is compared to uniform recharge rates. Water table elevations below the well exposed high‐relief mountain ridges are observed to be more sensitive to changes in groundwater recharge rates and permeability than below ridges with less topographic relief. In the conceptual framework of the numerical simulations, the model fault zone has less influence on the groundwater table position, but more importantly acts as fast flow path for recharge from glaciated areas towards the subsurface galleries. This is in agreement with a previous study, where the imprint of glacial recharge was observed in the environmental isotope composition of groundwater sampled in the subsurface galleries. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献