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This article presents new data on the abundance and ways of dissolved trace elements (Si, Fe, F, Al, Sr, Br, B, Mn, Ba, Ti, Li, Rb, Mo, As, U, Th, W, Sc, Y, REE, and Hf) in thermomineral, surface, and ground waters of the northern Tien Shan (Issyk-Kul intermountain depression). It has been established that the trace element composition of thermomineral waters can serve as a marker of hydrogeological settings of water formation and flow: waters of sedimentary rocks of the intermountain artesian basin are enriched with Sr, Ba, Mn, B, Mo, and U, while the waters of rock massifs contain increased concentrations of F, Rb, W, and Sc. Thermodynamic calculations performed for certain trace elements in Visual-MINTEQ 3.1 and GWB 14 have made it possible to identify the water migration patterns of the surveyed water points. Calculation of the water migration coefficient has shown the dependence of the rate of microcomponent accumulation on the type of water-bearing strata and hydrogeological conditions of water formation. [ABSTRACT FROM AUTHOR]

A comparative analysis of the chemical composition of underground brines in sections of the Tunguska and Olenek artesian basins is accomplished. The paper examines the equilibrium degree of brines with host rock minerals: carbonate (dolomite, calcite, magnesite, strontianite), sulfate (gypsum and celestine), chloride (halite, sylvite) and some aluminosilicates (anorthite, albite, illite, montmorillonites, kaolinite, muscovite, and others). Origin of brines is discussed based on results of the calculation of genetic coefficients. The paper presents a schematic generalization of data on the chemical composition, mineral concentration, genesis, and abundance of brines in the studied subjects. [ABSTRACT FROM AUTHOR]

Analyses for 81 Kr and noble gases on groundwater from the deepest aquifer system of the Baltic Artesian Basin (BAB) were performed to determine groundwater ages and uncover the flow dynamics of the system on a timescale of several hundred thousand years. We find that the system is controlled by mixing of three distinct water masses: Interglacial or recent meteoric water (δ 18 O ≈ −10.4‰) with a poorly evolved chemical and noble gas signature, glacial meltwater (δ 18 O ⩽ −18‰) with elevated noble gas concentrations, and an old, high-salinity brine component (δ 18 O ⩾ −4.5‰, ⩾ 90 g Cl − /L) with strongly depleted atmospheric noble gas concentrations. The 81 Kr measurements are interpreted within this mixing framework to estimate the age of the end-members. Deconvoluted 81 Kr ages range from 300 ka to 1.3 Ma for interglacial or recent meteoric water and glacial meltwater. For the brine component, ages exceed the dating range of the ATTA-3 instrument of 1.3 Ma. The radiogenic noble gas components 4 He ∗ and 40 Ar ∗ are less conclusive but also support an age of > 1 Ma for the brine. Based on the chemical and noble gas concentrations and the dating results, we conclude that the brine originates from evaporated seawater that has been modified by later water–rock interaction. As the obtained tracer ages cover several glacial cycles, we discuss the impact of the glacial cycles on flow patterns in the studied aquifer system. [ABSTRACT FROM AUTHOR]

Mathematical simulation techniques have been used to study the subsurface water-lake system. The volume of the subsurface drain from the Syrdarya artesian basin (Kazakhstan) into the Aral Sea depression was computed subject to the geoinformation-mathematical model of its hydrogeological conditions. Since the surface and subsurface (underground) water are interconnected, their movement has been measured during the undisturbed period (1960), the epignostic (1961–2014) period, and for forecasting problems for 2044 under two water withdrawal options. The first forecast option assumes the same withdrawal volume of subsurface water level which existed at the end of 2014. The second forecast option envisages the model assignment (from the start of 2015) of the water withdrawal in the production volumes of the subsurface water approved by the National Reserves Committee of the Republic of Kazakhstan. The simulation results showed that the technogenic factors in the explored area have a significant impact on the movement of the subsurface and surface water. Reduction of the Syrdarya and Amudarya rivers flows, production of subsurface water with multiple water-intake and unowned self-flowing wellbores promoted the desiccation of the Aral Sea. The proposed mathematical simulation technique used to assess the subsurface drain proved its efficiency and can be used for surveying the similar subsurface water-lake systems. [ABSTRACT FROM PUBLISHER]

Although potential contamination of groundwater As is expected to occur in Xinjiang, P.R. China, few data are available for the regional distribution of groundwater As. In this study, the spatial distribution of groundwater As was investigated in the Chepaizi (CPZ-N) and Shihezi (SHZ-N) areas of northern Xinjiang, the Balikun-Yiwu Basin (BY-E) in eastern Xinjiang, and the Tarim (TRM-S) and Yanqi (YQ-S) basins in southern Xinjiang. Arsenic concentrations greater than 10 μg/L were found in 12% of analyzed groundwaters. All groundwater samples collected in CPZ-N had As concentrations greater than 10 μg/L (25–185 μg/L), 30% in SHZ-N (<0.25–49 μg/L), 2.7% in BY-E, and 6.1% in TRM-S and YQ-S. No high As groundwater (As >10 μg/L) was found in the eastern and southern TRM-S and YQ-S. Distribution of groundwater As showed a tremendous spatial variability, which greatly varied over a short distance horizontally. Arsenic concentration generally increased with increasing sampling depth. The spatial distribution of groundwater As would be regulated by As source and hydrogeochemical processes. Higher pH and/or lower ORP values were generally observed in high As groundwater (>10 μg/L) in comparison with low As groundwater (<10 μg/L). Arsenic mobility in SHZ-N and CPZ-N may result from As desorption under relatively high pH conditions, and more tentatively from reductive dissolution of Fe(III) oxides in BY-E and TRM-S. However, detailed mechanisms of As mobilization in these regions need further investigation. [ABSTRACT FROM AUTHOR]

Throughout the world, high artesian pressures in hydrothermal areas have led to the growth of tall spring towers that have their vents at their summits. The factors that control their development and formative precipitates are poorly understood because these springs, irrespective of location, are mostly inactive. Spring towers found at Shiqiang (Yunnan Province, China), which are up to 4 m high and 3 m in diameter, are formed largely of calcite and aragonite crystal bushes, euhedral calcite crystals and coated grains with alternating Fe-poor and Fe-rich zones, calcite rafts, and cements formed of various combinations of calcite, aragonite, strontianite, Mg-Si reticulate, needle fiber calcite, calcified and non-calcified microbes, diatoms, and insects. Collectively, the limestones that form the towers can be divided into (1) Group A that are friable, porous and form the cores of the towers and have δ 18 O SMOW values of + 15.7 to + 19.7‰ (average 17.8‰) and δ 13 C PDB values of + 5.1 to + 6.9‰ (average 5.9‰), and (2) Group B that are hard and well lithified and found largely around the vents and the tower sides, and have δ 18 O SMOW values of + 13.0 to + 22.0‰ (average 17.6‰) and δ 13 C PDB values of + 1.4 to + 3.6‰ (average 2.6‰). The precipitates and the isotopic values indicate that these were thermogene springs. Growth of the Shiqiang spring towers involved (1) Phase IA when precipitation of calcite and aragonite bushes formed the core of the tower and Phase IB when calcite, commonly Fe-rich, was precipitated locally, (2) Phase II that involved the precipitation of white cements, formed of calcite, aragonite, strontianite, and Mg-Si reticulate coatings in cavities amid the Phase I precipitates, and (3) Phase III, which formed probably after spring activity ceased, when needle-fiber calcite was precipitated and the mounds were invaded by microbes (some now calcified), diatoms, and insects. At various times during this complex history, pore waters mediated dissolution of the calcite and aragonite and sometimes partial alteration of the aragonite. The diverse array of precipitates, depositional fabrics and diagenetic changes clearly indicate that the composition of the spring water changed frequently. Growth of the spring towers at Shiqiang continued until there was insufficient artesian pressure to lift the water above the top of the tower vent. [ABSTRACT FROM AUTHOR]

A new data set of δ2H and δ18O in the groundwater from the central part of the Baltic Artesian Basin is presented. The hydrogeological section is subdivided into stagnation, slow exchange and active exchange zones. Na–Ca–Cl brine found at the deepest part – the stagnation zone – is characterized by δ18O values above −5 ‰ and δ2H values approaching −40 ‰ with respect to Vienna Standard Mean Ocean Water. The slow exchange zone where waters of mostly intermediate salinity reside is characterized by δ18O values around −11.7 ‰ and δ2H values around −85.3 ‰. Mean δ18O and δ2H values of the fresh groundwater in the active water exchange zone are −11.1 and −79.9 ‰, respectively. Characteristically, the groundwater in the active and slow exchange zone is isotopically more depleted compared with the precipitation values observed, and the depletion increases with depth down to the level where strongly enriched brines are encountered. [ABSTRACT FROM PUBLISHER]

Copyright of Hydrogeology Journal is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrogeology Journal is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Although it has been reported that flowing artesian wells could be topographically controlled, there is no quantitative research on artesian flow conditions in unconfined aquifers. In this study, the water table, which has a lower amplitude than the land surface, is damped from the topography and used as the boundary condition to obtain the analytical solution of hydraulic head of a unit basin with a single flow system. The term artesian head is defined to characterize the condition of flowing artesian wells. The zone with positive artesian head is called artesian zone while with negative artesian head is nonartesian zone. The maximum artesian head and the size of artesian zones are found to increase with the damping factor and the anisotropy ratio, and decrease with the ratio of basin width to depth and the depth-decay exponent of hydraulic conductivity. Moreover, the artesian head increases with depth nearby the valley and decreases with depth near by the divide, and the variation rates are influenced by the decay exponent and the anisotropy ratio. Finally, the distribution of flowing artesian wells and the artesian head measurements in different depths of a borehole in a small catchment in the Ordos Plateau, Northwestern China is used to illustrate the theoretical findings. The change in artesian head with depth was used to estimate the anisotropy ratio and the decay exponent. This study opens up a new door to analyze basin-scale groundwater flow. [ABSTRACT FROM AUTHOR]

The paper describes the indispensable functional relationship between large-scale hydrocarbon trap saturation and limited space overflow-injection hydrogeological processes outside the regional action of elision and artesian mechanisms. We propose a set of qualitative criteria and quantitative indicators of oil and gas potential, making it possible to minimize the risks of geological exploration and production and create individual forecast zones and priority areas of oil and gas accumulation. [ABSTRACT FROM AUTHOR]

The Pale di San Martino and Pale di San Lucano (referred to together as the 'Pale') are remnants of an originally more extensive carbonate platform in the Dolomite Mountains of northern Italy. The platforms are composed of Middle Triassic dolomites and limestones up to 1.6km thick. Limestones comprise 2-3% of the platform carbonates and are restricted to narrow corridors (tens to a few hundred metres wide, hundreds of metres long and high) within the dolomite. The mainly sucrosic dolomites of the Pale are interpreted as the result of recrystallization of a depositional, nearly stoichiometric Mg calcite under burial temperatures of ca. 40-70°C. The principal arguments are: The quantitative composition indicates that all platform carbonates are composed mainly of micritic crusts (45%; boundstone fabric prevails) and early cement (35%; microcrystalline, fibrous). The platform carbonates were probably mainly bacterial precipitates and tight at the sediment-water interface (porosities <5%, permeabilities in the micro-Darcy range)., The limestone-dolomite transitions (centimetres to decimetres wide) lack dolomite gradients. The lack of evidence for flowing fluids causing dolomitization suggests stagnant pore waters., The δ13C of average dolomite is 1.3‰ heavier than that of coeval limestone (666 analyses). The difference corresponds to a primary difference of 50mol% MgCO3 and is interpreted as the result of fractionation. It suggests a dolomite precursor of very high Mg calcite, whereas present-day limestone of the Pale was probably deposited as a basically Mg-free polymorph (aragonite and/or calcite)., The dolomite δ18O (+1 to −11‰ VPDB) values show a scatter over the platform thickness and preserve randomly distributed values around 0‰. The scatter is probably due to selective re-setting of δ18O near pore spaces and is mainly a sampling effect., The observation that 87Sr/86Sr ratios (77 analyses) of limestone and dolomite are either slightly higher or lower than Middle Triassic seawater, but almost never 'normal marine', suggests that the platform carbonates of the Pale were deposited from seawater contaminated with artesian freshwater. The limestone corridors are probably caused by artesian springs of somewhat higher than ambient depositional temperature, with low Mg calcite and/or aragonite deposited in or near fracture zones. The volumetrically subordinate cycle-cap dolomite is possibly a primary precipitate. [ABSTRACT FROM AUTHOR]

Artificial artesian wells have existed in the San Luis Valley of south central Colorado for over 100 years, and they are an important source of water for livestock and wildlife. When Great Sand Dunes National Park and Preserve (GRSA) expanded its boundaries in 2000, ten of these wells were within the new park boundary. Because the habitat surrounding the wells was so severely disturbed by cattle and wildlife trampling, the National Park Service capped the wells in 2010 to promote restoration of the areas to a more natural state. To study changes after well-capping, we compared the plant communities in 2011 and 2012. We measured and compared plant cover, species frequency, and species diversity at recently capped wells on GRSA, at flowing wells (i.e., with water) on adjacent private lands of The Nature Conservancy, and at reference sites. In general, there was little difference in percentage of plant cover and species diversity between well types. For percent cover, annual variation and distance from wellheads were the best predictors for the native and exotic plant species, respectively. Plant species composition varied by well type, with reference sites having the greatest frequency of native plants per site and capped well sites having the greatest frequency of exotic plants per site. For native plants, reference sites had the highest species diversity, while capped wells had the highest community evenness. Overall, our results suggest that in the short term, native plant populations have changed little after well-capping, but the frequency of exotic plants has increased at capped well sites relative to reference sites. [ABSTRACT FROM AUTHOR]

A series of thermodynamic simulations was carried out at varied physicochemical parameters within the framework of a single model experiment in a marginal part of an artesian basin. The transformation of the pore space is proved to be more significantly dependent on temperature than on the initial porosity of the rocks. The extent to which the water-rock system is open (or closed) plays a subordinate role in trans-forming the porosity of the rocks via indirectly controlling the leaching conditions of carbonate rocks. The filtration rate only insignificantly affects the saturation of the groundwaters at certain sites within the aquifer at given P- T parameters. In analyzing this criterion, the mineralogical composition of the host rocks plays the leading role. [ABSTRACT FROM AUTHOR]

The groundwater in the Cambrian–Vendian aquifer system with its δ 18 O water values of about − 22‰ (VSMOW) and a low radiocarbon concentration is of glacial origin from the Last Ice Age. Earlier surveys have highlighted a negative co-variance of sulphate and bicarbonate content in the groundwater of the Cambrian–Vendian aquifer system, whereas the most depleted dissolved inorganic carbon δ 13 C values have been measured mainly in groundwater samples with the lowest sulphate concentrations. In this paper we studied the origin of sulphate and the factors controlling the sulphur and carbon isotope geochemistry in the aquifer system. Direct sources of sulphate were not found, but relying upon δ 18 O SO 4 measurements we suggest that the sulphate originates from oxidation of sulphide minerals whereas the δ 34 S of the dissolved SO 4 2 − in the groundwater is more enriched than the δ 34 S of the surrounding rocks. We show that bacterial activity may have caused the enrichment of δ 34 S of sulphate. [ABSTRACT FROM AUTHOR]

Abstract: We report the observation of possible (hydraulic) open-system pingos (OSPs) at the mid latitudes ( S) in and around the Argyre impact-basin. OSPs are perennial (water)–ice cored mounds; they originate and evolve in periglacial and pro-glacial landscapes on Earth where intra- or sub-permafrost water under hydraulic/artesian pressure uplifts localised sections of surface or near-surface permafrost that then freezes in-situ. We invoke three lines of evidence in support of our analogue-based interpretation: (1) similarities of shape, size and summit traits between terrestrial OSPs and the Martian mounds; (2) clustered distribution and the slope-side location of the mounds, consistent with terrestrial permafrost-environments where OSPs are found; and, (3) spatially-associated landforms putatively indicative of periglacial and glacial processes on Mars that characterise OSP landscapes on Earth. This article presents five OSP candidate-locations and nests these mound locations within a new geological map of the Argyre impact-basin and margins. It also presents three periglacial hypotheses about the possible origin of the water required to develop the mounds. Alternative (non-periglacial) formation-hypotheses also are considered; however, we show that their robustness is not equal to that of the periglacial ones. [Copyright &y& Elsevier]

The paper presents control water jets and the lights for a fountain with PLC. Command can be synchronized with a musical background or with a generated sequence of control of jets and lights. [ABSTRACT FROM AUTHOR]

New data are given regarding to groundwater chemistry in the top hydrodynamic zone, including swamp waters, in West Siberian region. It was found that Fe is almost ubiquitous in the examined waters. Its maximal concentrations are typical of depths from a few to 200 m, where gley geochemical medium predominates and high concentrations of dissolved organic matter are recorded. Thermodynamic methods are used for the first time to calculate the equilibrium of different waters with minerals of water-bearing rocks. Groundwater are shown to be in equilibrium with Al and Fe hydroxides; Ca, Mg, Fe carbonates; and clay minerals, including ferruginous. The swamp waters are also in equilibrium with blue iron earth and apatite. The conclusion is made that the sources of Fe, as well as other chemical elements, are minerals of primary aluminum-silicate rocks, with which the waters are never in equilibrium, and which they actively dissolve. [ABSTRACT FROM AUTHOR]

Artesian springs are localized aquifer outlets that originate when pressurized ground water is allowed to rise to the surface. Computing artesian discharge directly is often subject to practical difficulties such as restricted accessibility, abundant vegetation or slow flow rates. These circumstances call for indirect approaches to quantify flow. This paper presents a method to estimate ground water discharge through an upwelling spring by means of a three-layer steady-state groundwater flow model. Model inputs include on-site measurements of vertical sediment permeability, sediment temperatures and hydraulic gradients. About 70 spring bed piezometers were used to carry out permeability tests within the spring sediments, as well as to quantify the hydraulic head at different depths below the discharge point. Sediment temperatures were measured at different depths and correlated to permeabilities in order to demonstrate the potential of temperature as a substitute for cumbersome slug tests. Results show that the spatial distribution of discharge through the spring bottom is highly heterogeneous, as sediment permeability varies by several orders of magnitude within centimetres. Sensitivity analyses imply that geostatistical interpolation is irrelevant to the results if field datasets come from a sufficiently high resolution of piezometric records. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Copyright of Hydrogeology Journal is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The work is dedicated to catagenetic transformations in sedimentary rocks with consideration of defluidization in clayey and evaporite sediments and analysis of salt tectonics and hydrogeology in the North Caspian depression. [ABSTRACT FROM AUTHOR]

Water security has been recently defined as the capacity of a population on ensuring that they continue to have access to safe and properly sanitised potable water. Today, water security issues encompass increasing concerns arising from population growth, drought, climate change, oscillations between "El Nino" and "La Nina" effects, urbanisation, increasing salinity (e.g. the Arabian Gulf region), upstream pollution (for rivers), over-allocation of water licences by government agencies and over-utilisation of groundwater from artesian basins. All these distresses combined have resulted in a rapid decline in water security for many parts of the world, triggering off impacts of suffering to regions, states and countries, while tensions tend to exist between "upstream" and "downstream" users of water within individual jurisdictions (as throughout history, there has been much conflict over the use of water from rivers (such as the Nile, the Tigris and the Euphrates rivers)). In modern days, in many parts of the world, water security is mostly sought by implementing water desalination, pipelines between sources and users, water licences with different security levels and (sadly to say) war; while water allocation between competing users is increasingly determined by application of market-based pricing for either water licences or actual water. As water desalination is a crucial topic on the water security agenda worldwide, this paper shall examine interrelated issues concerning water management and water privatisation (global and in the Kingdom of Bahrain, with some focus on the preparedness of Kingdom of Bahrain for emergency situations), and shall briefly underline the countries and regions of the world that are suffering most from water stress (like North Africa, Middle East, Central Asia, China, Chile, South Africa and Australia). [ABSTRACT FROM AUTHOR]

1. The relative importance of contemporary and historical processes is a fundamental question in understanding patterns of biodiversity. We tested the hypothesis that species-sorting into different habitats (limnocrenes, rheocrenes, helocrenes), rather than history, would account for the greatest variation in macroinvertebrate diversity in desert artesian springs of The Bonneville Basin, U.S.A. These springs were isolated at the valley scale c. 9000 years ago by aridity and high salinity. Thus, the valley scale will account for the greatest variation in community composition if history and dispersal limitation are important, whereas niche-based sorting processes will be most important if habitat accounts for the greatest variation in community composition. 2. We identified 302 taxa from 280 sites and used a partial redundancy analysis, additive partitioning and classification strength (CS) to partition the variability in diversity among the springs. The valley scale accounted for more variation in community composition in limnocrene habitats (32.5%) than all other spatial and environmental variables combined. Valleys also accounted for 58% (additive partitioning) and 83% (CS) of the regional variation in diversity in analyses that included all three habitat types. That is, the average community similarity was 25% across the region, but increased to 41% within valleys. By contrast, habitat filtering did not account for significant variation in community composition in any of the analyses. Our study is one of the few suggesting the over-riding importance of neutral processes in determining patterns of diversity (history and dispersal limitation). 3. The 'expansion' hypothesis suggests that the youthful age of a region, combined with slow dispersal by a fauna dominated by generalists, will maximise the imprint of history. These communities appear to exist in a pre-equilibrial state, where the maximum carrying capacity has not been reached and niche space is plentiful. With time, we predict that local richness will increase while β-diversity decreases as species expand their distribution across the region. Consequently, the importance of niche-based processes may increase with time as the imprint of history fades. [ABSTRACT FROM AUTHOR]

Abstract: Evaporation losses from unconfined groundwater can form an important part of the water balance of arid zone groundwater systems. However, in artesian groundwater systems, the discrimination between artesian leakage and surface recharge contributions to the unconfined water table is required. We use hydrochemical analysis techniques and isotopic data to investigate the provenance of unconfined groundwater in zones of artesian discharge along the margin of the Great Artesian Basin (GAB) of Australia. Forward modelling of evapoconcentration and use of trilinear plots identified unconfined groundwater that was largely derived from fluvial recharge, compared to upwards artesian leakage, particularly in areas where the artesian groundwater had a Na-HCO3-Cl composition in contrast to the Na-Cl-SO4 composition more typical of arid zone meteoric recharge. Mixing models, combined with forward evapoconcentration models, confirmed that the contribution of artesian groundwater was minimal in areas of Na-Cl-SO4 unconfined groundwater underlain by Na-HCO3-Cl artesian groundwater. However, the evaporation modelling was still useful in identifying probable artesian versus meteoric contributions from Na-Cl-SO4 composition artesian groundwater Stable isotope data were consistent with the unconfined groundwater being evapoconcentrated from the artesian groundwater end-member and were unable to discriminate between contributions from fluvial recharge and artesian discharge. The hydrochemical analysis techniques can assist in water balance studies of aquifers with Na-HCO3-Cl composition groundwater discharging into semi-arid and arid environments, in addition to identifying areas of local fluvial recharge. [Copyright &y& Elsevier]

The Neolithic site KS043, excavated by the Institut français d'archéologie orientale (IFAO), is situated in the southern basin of the Kharga Oasis (Egypt). It is one of the very few stratified prehistoric sites of the eastern Sahara. The archaeological remains were found near artesian springs that provided water for pastoralists during the dry Middle Holocene. In situ settlement features provided well-preserved material (charcoal, ashy sediment, ostrich eggshell) sufficient to perform radiocarbon dating in the IFAO laboratory in Cairo by the conventional liquid scintillation method. In 2 cases, ostrich eggshell and charcoal within the same in situ context gave significantly different results of, respectively, 600 and 1200 yr younger dates for the ostrich eggshells. The strong discrepancy is here highlighted for the first time and we suggest that it may be linked with postdepositional phenomena in the vicinity of the artesian springs. A thorough review of 14C dates available for the Holocene in eastern Sahara shows that ostrich eggshells have been widely used. They seem slightly more prone to be discarded than other material but were never the object of a particular study in this context. Bayesian modeling shows that the Neolithic occupation at site KS043 spans a range from 5000 to 3950 cal BC (and concentrated around 4600-4350 cal BC). Characteristic flint tools and pottery relate this occupation to the end of the Neolithic and show links with the Tasian culture, confirming the timing of the presence of this cultural complex in the desert before its appearance in the Nile Valley. [ABSTRACT FROM AUTHOR]

Studying results of the groundwater isotope composition in the Neogene-Quaternary and Mesozoic sediments of the Azov-Kuban and Eastern Pre-Caucasian artesian basins have shown in the Pliocene sediments a rather wide distribution of 'relict' groundwater, formed because of melting of the Late Pleistocene Caucasian glaciers, as well as of groundwater formed due to its mixing with the meteogenic waters of the subsequent Holocene infiltration cycles. Also, the areas are revealed in the Lower-Miocene sediments where meteogenic waters are mixed with sedimentation waters, while in the Mesozoic formations-the areas where into the sedimentation waters wedge-shaped meteogenic waters of Pleistocene and Holocene infiltration periods are intruded. [ABSTRACT FROM AUTHOR]

We have proposed the classification of nanoparticles in natural waters by the mechanism of the formation and chemical composition. We have obtained data according to the dimensional spectrum and the content of microelements aluminosilicate particles of artesian waters. [ABSTRACT FROM AUTHOR]

Copyright of Hydrogeology Journal is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the potential climatic and anthropogenic-induced changes in the spring discharge volumes of Comal Springs, the artesian spring in Edwards Aquifer (EA), Texas. The study uses methods including the examination of the impact of pumping on discharge characteristics and the demonstration of flow teleconnections. It concludes that the correlation for spring, summer, and fall seasons is statistically significant in terms of discharge variability.

Abstract: We tested two methods for dating groundwaters that cannot be reliably measured by 36Cl dating alone, one based on groundwater flow velocity plus distance along a flow path and the other based on 4He accumulation rates calibrated with 36Cl dates. We sampled groundwaters along six inferred regional groundwater flow paths in the Great Artesian Basin (GAB) of Australia. We selected three groundwater paths where the decrease in 36Cl was largely controlled by cosmogenic 36Cl radioactive decay without a significant increase in chloride concentration. The extrapolated groundwater velocities were 0.133±0.018 m/y to 0.433±0.140 m/y. The estimated residence time of 1.06×106 y at the discharge area around Lake Eyre was comparable to the estimate of (1–2.2)×106 y in previous studies. On the other hand, our estimated 4He accumulation rates for the selected three groundwater flow paths (1.85±0.31×10−11 to 1.51±0.63×10−10 ccSTP/cm3∙y) were approximately 2–15 times lower than previously reported rates for the central GAB. Our estimated rate of 1.51×10−10 ccSTP/cm3∙y−1 in the western GAB is compatible with previous estimates based on 81Kr ages. The groundwater residence time estimated from the 4He accumulation rate was approximately 7×105 y near the discharge area at Lake Eyre. Finally, both estimations were mutually compatible with a 30% error. [Copyright &y& Elsevier]

DNA, as the signature of life, has been extensively studied in a wide range of environments. While DNA analysis has become central to work on natural gene exchange, forensic analyses, soil bioremediation, genetically modified organisms, exobiology, and palaeontology, fundamental questions about DNA resistance to degradation remain. This paper investigated on the presence of plant DNA in groundwater and artesian fountain (groundwater-fed) samples, which relates to the movement and persistence of DNA in the environment. The study was performed in the groundwater and in the fountains, which are considered as a traditional artesian drinking water in Geneva Champagne Basin. DNA from water samples was extracted, analysed and quantified. Plant gene sequences were detected using PCR amplification based on 18S rRNA gene primers specific for eukaryotes. Physicochemical parameters of water samples including temperature, pH, conductivity, organic matter, dissolved organic carbon (DOC) and total organic carbon (TOC) were measured throughout the study. The results revealed that important quantities of plant DNA can be found in the groundwater. PCR amplification based on 18S rDNA, cloning, RFLP analysis and sequencing demonstrated the presence of plant DNA including Vitis rupestris, Vitis berlandieri, Polygonum sp. Soltis, Boopis graminea, and Sinapis alba in the water samples. Our observations support the notion of plant DNA release, long-term persistence and movement in the unsaturated medium as well as in groundwater aquifers. [Copyright &y& Elsevier]

The artesian springs that are located on the edge of the Great Artesian Basin in arid South Australia support diverse assemblages of spiders. Domestic or feral stock have affected the vegetation and substrate of artesian springs, which are important water sources. The effects of stock on the spider communities of artesian springs were investigated with a descriptive survey, comparing springs with differing grazing histories, and with a field experiment that simulated the impacts of cattle presence with trampling and mowing treatments. In the survey, the abundance of spiders was associated with the dominant vegetation cover and with the history of grazing pressure. In the experiment, the abundance of web-building and ambush-hunting spiders declined following mowing and/or trampling treatments. The use of foraging guilds is likely to be a useful approach in using spider communities as bioindicators of environmental change. [ABSTRACT FROM AUTHOR]

Pollution of potable water with natural elements is an important issue for many towns of central Russia. Study of the chemical composition and hydrodynamics of groundwaters made it possible to establish some regularity in the influence of the anthropogenic load and exploitation regime of water intake (hereafter, intake) on their quality. It is shown that the quantitative prognosis of pollution of water wells should be based on the complex study of geochemical, hydrodynamic, and economic conditions of water consumption. Solution of the problem concerning the quality of groundwater within natural-technogenic hydrogeochemical anomalies requires an integrated strategy of measures aimed at adaptation of the water consumption to limits of natural stability in the water basin and to reduction of the emission of technogenic toxic substances and greenhouse gases. It is recommended to carry out complex geochemical studies of the aquifer in order to predict the possible groundwater pollution by natural pollutants. The study is based on the results of analysis of 5000 samples carried out at the Chemical-Analytical Center of the Taifun Scientific-Industrial Enterprise of the Russian Hydrometeorological Center and the Vodokanal Small Enterprise (Obninsk). [ABSTRACT FROM AUTHOR]

Water levels in the karstic San Andres limestone aquifer of the Roswell Artesian Basin, New Mexico, display significant variations on a variety of time scales. Large seasonal fluctuations in hydraulic head are directly related to the irrigation cycle in the Artesian Basin, lower in summer months and higher in winter when less irrigation occurs. Longer-term variations are the result of both human and climatic factors. Since the inception of irrigated farming more than a century ago, over-appropriation of water resources has caused water levels in the artesian aquifer to fall by as much as 70 m. The general decline in hydraulic head began to reverse in the mid-1980s due to a variety of conservation measures, combined with a period of elevated rainfall toward the end of the 20th Century. [ABSTRACT FROM AUTHOR]

Inquiries into the diminishing supply of artesian water within the Queensland aspect of the Great Artesian Basin began in 1939. These investigations produced a Queensland phenomenon without Australian precedent in terms of rationale, geographical diversity, and commitment of resources. In some regions, exposure of herds to fluoride emerged as an urgent issue because fluoride was perceived as an invasive, invisible, and odourless 'contaminant' in artesian water. This paper discusses the scientific background to, and management of, concerns over the consumption by stock of artesian water with a high concentration of natural bioavailable fluoride. The Queensland Department of Agriculture and Stock managed the problem by scientific investigation, methodical field study, and the application of research findings to animal husbandry. The practical solutions arrived at involved rotation of stock on an age-related basis to and from certain bore supplies, fencing young sheep away from the artesian supply, fencing young sheep near the bore-head, and limiting the use of supplements. [ABSTRACT FROM AUTHOR]

This paper presents the results of geomorphologic-hydro sedimentlogy study done in the hydrographic basin of the Aquidorobó torrent and its area of influence in the municipio of Poxoréu, southeast of the state of Mato Grosso, in the geomorphic unit know as «meseta de los acantilados». The torrent studied is affluent of the Poxoréu River in the San Lorenço basin. The geomorphic-sedimentlogy works were made in the municipio Poxoréu and are related to the open-pits of common wells and artesian wells in some houses, farmsteads and others built to get water for common use. In general, companies charged of building the wells make water chemical analysis to show the owners the quality of the resource and abilities for personal consumption and other uses. [ABSTRACT FROM AUTHOR]

Abstract: New data on the geochemistry and isotopic composition of chloride brines of the Siberian Platform are presented. The distribution of stable isotopes (2H, 18O, and 37Cl) in brines of the Tunguska, Angara-Lena, western part of the Yakutian and Olenek artesian basins and 87Sr/86Sr in brines of the western part of the Olenek artesian basin was studied in the context of the problem of genesis of highly mineralized groundwaters. Results of the study and comparative analysis of the geochemical and isotopic peculiarities of the Siberian Platform brines conform to the theory of brine formation through the interaction of connate waters with enclosing rocks. [Copyright &y& Elsevier]

The major ion composition of Great Artesian Basin groundwater in the lower Namoi River valley is relatively homogeneous in chemical composition. Traditional graphical techniques have been combined with multivariate statistical methods to determine whether subtle differences in the chemical composition of these waters can be delineated. Hierarchical cluster analysis and principal components analysis were successful in delineating minor variations within the groundwaters of the study area that were not visually identified in the graphical techniques applied. Hydrochemical interpretation allowed geochemical processes to be identified in each statistically defined water type and illustrated how these groundwaters differ from one another. Three main geochemical processes were identified in the groundwaters: ion exchange, precipitation, and mixing between waters from different sources. Both statistical methods delineated an anomalous sample suspected of being influenced by magmatic CO2 input. The use of statistical methods to complement traditional graphical techniques for waters appearing homogeneous is emphasized for all investigations of this type. [ABSTRACT FROM AUTHOR]

The necessity of eliminating debris from a granite quarry has awakened an interest in applications of by-products, called “marginal arids”, in different fields, like construction and foundations for roadways, restoration, material for the manufacture of artificial rocks, and artesian products etc. Conclusions obtained from the results of tests carried out by X-ray diffraction of granite quarry by-products in Extremadura, Spain, submitted to different treatments, are established. Test pieces from two quarries are analyzed and compared generally and specifically, for commercial use. Finally, conclusions relating to essays in test pieces and mineral dynamics of marginal arid granite are exposed. [ABSTRACT FROM AUTHOR]

The development of gypsum maze caves under artesian conditions has been simulated. The numerical model simulations show that the evolution of maze caves in this type of setting requires structural preferences such as laterally extended fissure networks in a horizon of the gypsum layer. Without any structural preferences vertical shafts rather than maze caves are predicted to develop. The most important stage for the development of horizontal caves under artesian conditions is found to be the initial karstification period. During this period the structure of the mature conduit system is established. The solutional enlargement of conduits is spatially extended, total dissolution rates are higher than the later ones. [ABSTRACT FROM AUTHOR]

The formation of the fresh groundwater natural resources of the platform territories is analyzed. It is shown that within the artesian areas of platforms, the formation of the fresh groundwater natural resources is governed by the following main factors: the climatic conditions of the territory; the geological-structural features of the basin, substantially different in its peripheral and central parts; the structure of the zone of intense water exchange; the type of the water-bearing rocks and the character of the spatial variability of their hydraulic parameters; the aeration zone composition; the specific features of interaction between the groundwater and the hydrographic network and micro-relief of the territory. It is emphasized that the formation of the fresh groundwater natural resources within the hydrogeological massifs is governed not only by the physical-geographical conditions, but by the geological-structural factors as well. The formation and distribution of groundwater resources are governed by numerous natural and anthropogenic factors [11]. The combination of these factors and the significance of each factor are not constant but considerably vary in space, depending on the physical-geographical, geological, and hydrogeological conditions. [ABSTRACT FROM AUTHOR]

Artesian basins contain the largest mineral water resources of the world. There are several types of mineral therapeutic water: sulfate, chloride, radon-rich, iron-rich waters, etc. Artesian basins occupy very large areas in Russia. However, genesis of water and brines is still not very clear. This is one of the most important hydrogeological problems that is being attempted to solve for many years. Most of the Russian hydrogeologists traditionally consider that these waters are of sedimentary origin. However, higher concentrations of bromine, iodine, iron, radon and other balneologically active components can be of different origin, for example, of infiltration or juvenile water. As an example, two areas will be considered - West-Siberian basin and East-European artesian area.West-Siberian artesian basin has very distinct latitudinal and vertical zonation. Latitudinal zonation is caused by climate changes from north to south. As for the vertical zonation, mineralization and chemical composition change in the vertical cross-section and from the periphery to the center within the same aquifer. The main mineral water resources of West-Siberian artesian basin are concentrated in Mesozoic rocks. Brackish waters and low-saturated brines without specific components are used for medical purposes. The most well-known spa is Karachi, which exploits chloride-hydrocarbonate brackish water. Sodium chloride bromine and iodine-bromine waters are used at other health resorts. It is possible to organize extraction of iodine from brines of Tcherkashinsko-Tobolskoe occurrence in Tumen region.East-European artesian area occupies most of the Russian Platform. The most widespread types of mineral water within the Russian Platform are sodium-chloride and magnesium-sulfate waters and brines. Such well-known spas, like Moscow mineral waters, Krainka, Staraya Russa and many others, belong to this type. Resources of these waters are definitely connected with sedimentogenic processes. The upper hydrodynamic zone contains iron-rich, hydrogen sulfide, and sometimes radon-rich water. Their formation is caused by the interaction between waters of infiltration and sedimentary genesis, or between infiltration waters and host rocks. One of the examples is Polustrovo iron-rich water. There are industrially valuable waters containing bromine and iodine.The resources of therapeutic water of sedimentary basins allow to increase balneological potential of spas in Russia. [ABSTRACT FROM AUTHOR]