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Estimating groundwater inflow and leakage outflow for an intermontane lake with a structurally complex geology: Georgetown Lake in Montana, USA | Estimation des flux d’eaux souterraines d’entrée et de sortie par fuite d’un lac de montagne en contexte géologique structural complexe : lac de Georgetown dans le Montana (Etats-Unis d’Amérique) Estimación de la afluencia y efluencia por filtración del agua subterránea en un lago intermontano con una geología estructuralmente compleja: Lago Georgetown en Montana, EEUU 利用结构上复杂的地质条件估算山间湖泊地下水流入量及渗漏流出量:美国蒙塔纳州乔治城湖 Estimando a afluência das águas subterrâneas e saída por escoamento para um lago entre montanhas com uma geologia estruturalmente complexa: Lago Georgetown em Montana, EUA Full text
2017
Shaw, Glenn D. | Mitchell, Katie L. | Gammons, Christopher H.
Stable isotopes of the water molecule (δ¹⁸O and δD) for groundwater, lake water, streams, and precipitation were coupled with physical flux measurements to investigate groundwater–lake interactions and to establish a water balance for a structurally complex lake. Georgetown Lake, a shallow high-latitude high-elevation lake, is located in southwestern Montana, USA. The lake is situated between two mountain ranges with highlands primarily to the east and south of the lake and a lower valley to the west. An annual water balance and (δ¹⁸O and δD) isotope balance were used to quantify annual groundwater inflows of 2.5 × 10⁷ m³/year and lake leakage outflows of 1.6 × 10⁷ m³/year. Roughly, 57% of total inflow to the lake is from groundwater, and 37% of total outflow at Georgetown Lake is groundwater. Stable isotopes of groundwater and springs around the lake and surrounding region show that the east side of the lake contains meteoric water recharged annually from higher mountain sources, and groundwater discharge to the lake occurs through this region. However, springs located in the lower western valley and some of the surrounding domestic wells west of the lake show isotopic enrichment indicative of strong to moderate evaporation similar to Georgetown Lake water. This indicates that some outflowing lake water recharges groundwater through the underlying west-dipping bedrock in the region.
Show more [+] Less [-]Challenges for creating a site-specific groundwater-use record for the Ozark Plateaus aquifer system (central USA) from 1900 to 2010 | Les défis pour créer un relevé d’utilisation des eaux souterraines pour le système aquifère des Plateaux Ozark (Centre des Etats-Unis d’Amérique) de 1900 à 2010 Desafíos para la creación de un registro específico de sitios de uso de agua subterránea para el sistema acuífero de Ozark Plateaus (EEUU central) de 1900 a 2010 创建1900年到2010年(美国中部)Ozark高原含水层系统特定场地地下水利用记录的挑战 Desafios para criação de um registro do uso das águas subterrâneas em um sítio específico para o sitema aquífero dos Platôs Ozark (EUA central) de 1900 a 2010 Full text
2017
Knierim, Katherine J. | Nottmeier, Anna M. | Worland, Scott | Westerman, Drew A. | Clark, Brian R.
Hydrologic budgets to determine groundwater availability are important tools for water-resource managers. One challenging component for developing hydrologic budgets is quantifying water use through time because historical and site-specific water-use data can be sparse or poorly documented. This research developed a groundwater-use record for the Ozark Plateaus aquifer system (central USA) from 1900 to 2010 that related county-level aggregated water-use data to site-specific well locations and aquifer units. A simple population-based linear model, constrained to 0 million liters per day in 1900, provided the best means to extrapolate groundwater-withdrawal rates pre-1950s when there was a paucity of water-use data. To disaggregate county-level data to individual wells across a regional aquifer system, a programmatic hierarchical process was developed, based on the level of confidence that a well pumped groundwater for a specific use during a specific year. Statistical models tested on a subset of the best-available site-specific water-use data provided a mechanism to bracket historic groundwater use, such that groundwater-withdrawal rates ranged, on average, plus or minus 38% from modeled values. Groundwater withdrawn for public supply and domestic use accounted for between 48 and 74% of total groundwater use since 1901, highlighting that groundwater provides an important drinking-water resource. The compilation, analysis, and spatial and temporal extrapolation of water-use data remain a challenging task for water scientists, but is of paramount importance to better quantify groundwater use and availability.
Show more [+] Less [-]A regional groundwater-flow model for sustainable groundwater-resource management in the south Asian megacity of Dhaka, Bangladesh | Ein regionales Grundwassermodell für ein nachhaltiges Grundwassermanagement in der südasiatischen Megacity von Dhaka, Bangladesch Modèle régional d’écoulement des eaux souterraines pour une gestion durable des ressources en eaux souterraines dans la mégapole de Dhaka du Sud de l’Asie, au Bangladesh Un modelo regional de flujo de agua subterránea para la gestión sostenible de los recursos de hídricos subterráneos en la megaciudad de Dhaka en el Asia meridional, Bangladesh 南亚特大城市孟加拉达卡地下水资源可持续管理的区域地下水流模型 Um modelo regional de fluxo de águas subterrâneas para a gestão sustentável dos recursos hídricos subterrâneos na megacidade do sul da Ásia de Daca, Bangladesh Full text
2017
Islam, Md Bayzidul | Firoz, A. B. M. | Foglia, Laura | Marandi, Andres | Khan, Abidur Rahman | Schüth, Christoph | Ribbe, Lars
The water resources that supply most of the megacities in the world are under increased pressure because of land transformation, population growth, rapid urbanization, and climate-change impacts. Dhaka, in Bangladesh, is one of the largest of 22 growing megacities in the world, and it depends on mainly groundwater for all kinds of water needs. The regional groundwater-flow model MODFLOW-2005 was used to simulate the interaction between aquifers and rivers in steady-state and transient conditions during the period 1981–2013, to assess the impact of development and climate change on the regional groundwater resources. Detailed hydro-stratigraphic units are described according to 150 lithology logs, and a three-dimensional model of the upper 400 m of the Greater Dhaka area was constructed. The results explain how the total abstraction (2.9 million m³/d) in the Dhaka megacity, which has caused regional cones of depression, is balanced by recharge and induced river leakage. The simulated outcome shows the general trend of groundwater flow in the sedimentary Holocene aquifers under a variety of hydrogeological conditions, which will assist in the future development of a rational and sustainable management approach.
Show more [+] Less [-]Geochemistry and hydrology of perched groundwater springs: assessing elevated uranium concentrations at Pigeon Spring relative to nearby Pigeon Mine, Arizona (USA) | Géochimie et hydrologie des émergences de nappes perchées : interprétation des fortes concentrations en uranium de la Source du Pigeon au regard de la proche Mine du Pigeon, Arizona (Etats-Unis d’Amérique) Hidrología y geoquímica de manantiales de agua subterránea colgada: análisis de las concentraciones elevadas de uranio en el Manantial Pigeon relacionado con las inmediaciones de la Mina Pigeon, Arizona (EEUU) 上层滞水泉的地球化学和水文状况:评价 (美国) 亚利桑那州Pigeon 矿附近Pigeon泉水中升高的铀含量摘要 Geoquímica e hidrologia de nascentes de aquíferos suspensos: avaliando concentrações elevadas de urânio na Nascente de Pigeon relativa à Mina de Pigeon nas proximidades, Arizona (EUA) Full text
2017
Beisner, Kimberly R. | Paretti, Nicholas V. | Tillman, Fred D. | Naftz, David L. | Bills, Donald J. | Walton-Day, Katie | Gallegos, Tanya J.
The processes that affect water chemistry as the water flows from recharge areas through breccia-pipe uranium deposits in the Grand Canyon region of the southwestern United States are not well understood. Pigeon Spring had elevated uranium in 1982 (44 μg/L), compared to other perched springs (2.7–18 μg/L), prior to mining operations at the nearby Pigeon Mine. Perched groundwater springs in an area around the Pigeon Mine were sampled between 2009 and 2015 and compared with material from the Pigeon Mine to better understand the geochemistry and hydrology of the area. Two general groups of perched groundwater springs were identified from this study; one group is characterized by calcium sulfate type water, low uranium activity ratio ²³⁴U/²³⁸U (UAR) values, and a mixture of water with some component of modern water, and the other group by calcium-magnesium sulfate type water, higher UAR values, and radiocarbon ages indicating recharge on the order of several thousand years ago. Multivariate statistical principal components analysis of Pigeon Mine and spring samples indicate Cu, Pb, As, Mn, and Cd concentrations distinguished mining-related leachates from perched groundwater springs. The groundwater potentiometric surface indicates that perched groundwater at Pigeon Mine would likely flow toward the northwest away from Pigeon Spring. The geochemical analysis of the water, sediment and rock samples collected from the Snake Gulch area indicate that the elevated uranium at Pigeon Spring is likely related to a natural source of uranium upgradient from the spring and not likely related to the Pigeon Mine.
Show more [+] Less [-]Stratigraphic and structural controls on groundwater flow in an outcropping fossil fan delta: the case of Sant Llorenç del Munt range (NE Spain) | Contrôles stratigraphiques et structuraux sur les écoulements d’eau souterraine dans un éventail deltaïque fossile: le cas du massif de Sant Llorenç del Munt (Nord-est. de l’Espagne) Controles estratigráficos y estructurales en el flujo de agua subterránea de un abanico deltaico fósil: el caso del macizo de Sant Llorenç del Munt (NE de España) 出露地表的化石扇形三角洲地层和构造对地下水流的影响:(西班牙东北部)Sant Llorenç del Munt range的研究案例 Controle estrutural e estratigráfico do fluxo das águas subterrâneas em um afloramento fóssil de um delta em leque: o caso de Sant Llorenç del Munt (NE Espanha) Full text
2017
Anglés, Marc | Folch, Albert | Oms, Oriol | Maestro, Eudald | Mas-Pla, Josep
Stratigraphic and structural controls on groundwater flow in an outcropping fossil fan delta: the case of Sant Llorenç del Munt range (NE Spain) | Contrôles stratigraphiques et structuraux sur les écoulements d’eau souterraine dans un éventail deltaïque fossile: le cas du massif de Sant Llorenç del Munt (Nord-est. de l’Espagne) Controles estratigráficos y estructurales en el flujo de agua subterránea de un abanico deltaico fósil: el caso del macizo de Sant Llorenç del Munt (NE de España) 出露地表的化石扇形三角洲地层和构造对地下水流的影响:(西班牙东北部)Sant Llorenç del Munt range的研究案例 Controle estrutural e estratigráfico do fluxo das águas subterrâneas em um afloramento fóssil de um delta em leque: o caso de Sant Llorenç del Munt (NE Espanha) Full text
2017
Anglés, Marc | Folch, Albert | Oms, Oriol | Maestro, Eudald | Mas-Pla, Josep
Hydrogeological models of mountain regions present the opportunity to understand the role of geological factors on groundwater resources. The effects of sedimentary facies and fracture distribution on groundwater flow and resource exploitation are studied in the ancient fan delta of Sant Llorenç de Munt (central Catalonia, Spain) by integrating geological field observations (using sequence stratigraphy methods) and hydrogeological data (pumping tests, hydrochemistry and environmental isotopes). A comprehensive analysis of data portrays the massif as a single unit, constituted by different compartments determined by specific layers and sets of fractures. Two distinct flow systems—local and regional—are identified based on pumping test analysis as well as hydrochemical and isotopic data. Drawdown curves derived from pumping tests indicate that the behavior of the saturated layers, whose main porosity is given by the fracture network, corresponds to a confined aquifer. Pumping tests also reflect a double porosity within the system and the occurrence of impervious boundaries that support a compartmentalized model for the whole aquifer system. Hydrochemical data and associated spatial evolution show the result of water–rock interaction along the flow lines. Concentration of magnesium, derived from dolomite dissolution, is a tracer of the flow-path along distinct stratigraphic units. Water stable isotopes indicate that evaporation (near a 5% loss) occurs in a thick unsaturated zone within the massif before infiltration reaches the water table. The hydrogeological analysis of this outcropping system provides a methodology for the conceptualization of groundwater flow in similar buried systems where logging and hydrogeological information are scarce.
Show more [+] Less [-]Stratigraphic and structural controls on groundwater flow in an outcropping fossil fan delta: the case of Sant Llorenç del Munt range (NE Spain) Full text
2017
Angles, Marc | Folch Sancho, Albert | Oms i Llobet, Oriol | Maestro i Maideu, Eudald | Mas Pla, Josep | Universitat Politècnica de Catalunya. Departament d'Enginyeria Civil i Ambiental | Universitat Politècnica de Catalunya. GHS - Grup d'Hidrologia Subterrània
The final publication is available at Springer via http://dx.doi.org/10.1007/s10040-017-1618-9 | Hydrogeological models of mountain regions present the opportunity to understand the role of geological factors on groundwater resources. The effects of sedimentary facies and fracture distribution on groundwater flow and resource exploitation are studied in the ancient fan delta of Sant Llorenç de Munt (central Catalonia, Spain) by integrating geological field observations (using sequence stratigraphy methods) and hydrogeological data (pumping tests, hydrochemistry and environmental isotopes). A comprehensive analysis of data portrays the massif as a single unit, constituted by different compartments determined by specific layers and sets of fractures. Two distinct flow systems—local and regional—are identified based on pumping test analysis as well as hydrochemical and isotopic data. Drawdown curves derived from pumping tests indicate that the behavior of the saturated layers, whose main porosity is given by the fracture network, corresponds to a confined aquifer. Pumping tests also reflect a double porosity within the system and the occurrence of impervious boundaries that support a compartmentalized model for the whole aquifer system. Hydrochemical data and associated spatial evolution show the result of water–rock interaction along the flow lines. Concentration of magnesium, derived from dolomite dissolution, is a tracer of the flow-path along distinct stratigraphic units. Water stable isotopes indicate that evaporation (near a 5% loss) occurs in a thick unsaturated zone within the massif before infiltration reaches the water table. The hydrogeological analysis of this outcropping system provides a methodology for the conceptualization of groundwater flow in similar buried systems where logging and hydrogeological information are scarce. | Peer Reviewed | Postprint (author's final draft)
Show more [+] Less [-]Insights and participatory actions driven by a socio-hydrogeological approach for groundwater management: the Grombalia Basin case study (Tunisia) | Aperçus et actions participatives guidées par une approche socio-hydrogéologique pour la gestion des ressources en eau: le cas d’étude du bassin de Grombalia (Tunisie) Perspectivas y acciones participativas impulsadas por un enfoque socio-hidrogeológico para la gestión del agua subterránea: estudio de caso de la Cuenca de Grombalia (Túnez) 地下水管理中一个社会-水文地质方法带动的深刻认识和参与性行动:(突尼斯)古兰巴利耶流域研究实例 Indagini e azioni partecipative realizzate tramite un approccio socio-idrogeologico per la gestione delle risorse idriche sotterranee: il caso dell’acquifero di Grombalia (Tunisia) Perspectivas e ações participativas conduzidas por uma abordagem socio-hidrogeológica para a gestão das águas subterrâneas: o estudo de caso da Bacia de Grombalia (Tunísia) Full text
2017
Tringali, C. | Re, V. | Siciliano, G. | Chkir, N. | Tuci, C. | Zouari, K.
Sustainable groundwater management strategies in water-scarce countries need to guide future decision-making processes pragmatically, by simultaneously considering local needs, environmental problems and economic development. The socio-hydrogeological approach named ‘Bir Al-Nas’ has been tested in the Grombalia region (Cap Bon Peninsula, Tunisia), to evaluate the effectiveness of complementing hydrogeochemical and hydrogeological investigations with the social dimension of the issue at stake (which, in this case, is the identification of groundwater pollution sources). Within this approach, the social appraisal, performed through social network analysis and public engagement of water end-users, allowed hydrogeologists to get acquainted with the institutional dimension of local groundwater management, identifying issues, potential gaps (such as weak knowledge transfer among concerned stakeholders), and the key actors likely to support the implementation of the new science-based management practices resulting from the ongoing hydrogeological investigation. Results, hence, go beyond the specific relevance for the Grombaila basin, showing the effectiveness of the proposed approach and the importance of including social assessment in any given hydrogeological research aimed at supporting local development through groundwater protection measures.
Show more [+] Less [-]Integrating an artificial intelligence approach with k-means clustering to model groundwater salinity: the case of Gaza coastal aquifer (Palestine) | Intégration d’une approche d’intelligence artificielle avec des moyennes de k par bouquet pour modéliser la salinité de l’eau souterraine: cas de l’aquifère côtier de Gaza (Palestine) Integración de un enfoque de inteligencia artificial con el agrupamiento de k-medios para modelar la salinidad del agua subterránea: el caso del acuífero costero de Gaza (Palestina) دمج تقنية الذكاء الصناعي مع وسيلة التصنيف "k-means" لنمذجة ملوحة المياه الجوفية : الحالة الدراسية، خزان قطاع غزة الجوفي (فلسطين) 人工智能方法与k-均值聚类结合在一起模拟地下水盐度:(巴勒斯坦)加沙沿海含水层的实例 Integrando uma abordagem de inteligência artificial com clusterização por k-means para modelar a salinidade das águas subterrâneas: o caso de um aquífero costeiro de Gaza (Palestina) Full text
2017
Alagha, Jawad S. | Seyam, Mohammed | Md Said, Md Azlin | Mogheir, Yunes
Artificial intelligence (AI) techniques have increasingly become efficient alternative modeling tools in the water resources field, particularly when the modeled process is influenced by complex and interrelated variables. In this study, two AI techniques—artificial neural networks (ANNs) and support vector machine (SVM)—were employed to achieve deeper understanding of the salinization process (represented by chloride concentration) in complex coastal aquifers influenced by various salinity sources. Both models were trained using 11 years of groundwater quality data from 22 municipal wells in Khan Younis Governorate, Gaza, Palestine. Both techniques showed satisfactory prediction performance, where the mean absolute percentage error (MAPE) and correlation coefficient (R) for the test data set were, respectively, about 4.5 and 99.8% for the ANNs model, and 4.6 and 99.7% for SVM model. The performances of the developed models were further noticeably improved through preprocessing the wells data set using a k-means clustering method, then conducting AI techniques separately for each cluster. The developed models with clustered data were associated with higher performance, easiness and simplicity. They can be employed as an analytical tool to investigate the influence of input variables on coastal aquifer salinity, which is of great importance for understanding salinization processes, leading to more effective water-resources-related planning and decision making.
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