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Geospatial and geostatistical approach for groundwater potential zone delineation 总被引:1,自引:0,他引:1 下载免费PDF全文
Javed Mallick Chander Kumar Singh Hussein Al‐Wadi Mohd Ahmed Atiqur Rahman Satyanarayan Shashtri Saumitra Mukherjee 《水文研究》2015,29(3):395-418
Over the past few decades, groundwater has become an essential commodity owing to increased demand as a result of growing population, industrialization, urbanization and so on. The water supply situation is expected to become more severe in the future because of continued unsustainable water use and projected change in hydrometeorological parameters due to climate change. This study is based on the integrated approach of remote sensing, geographical information system and multicriteria decision‐making techniques to determine the most important contributing factors that affect the groundwater resources and to delineate the groundwater potential zones. Ten thematic layers, namely, geomorphology, geology, soil, topographic elevation (digital elevation model), land use/land cover, drainage density, lineament density, proximity of surface water bodies, surface temperature and post‐monsoon groundwater depth, were considered for the present study. These thematic layers were selected for groundwater prospecting based on the literature; discussion with the experts of the Central Ground Water Board, Government of India; field observations; geophysical investigation; and multivariate techniques. The thematic layers and their features were assigned suitable weights on Saaty's scale according to their relative significance for groundwater occurrence. The assigned weights of the layers and their features were normalized by using the analytic hierarchy process and eigenvector method. Finally, the selected thematic maps were integrated using a weighted linear combination method to create the final groundwater potential zone map. The final output map shows different zones of groundwater potential, namely, very good (16%), good (35%), moderate (28%) low (17%) and very low (2.1%). The groundwater potential zone map was finally validated using the discharge and groundwater depth data from 28 and 98 pumping wells, respectively, which showed good correlation. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Shallow aquifer vulnerability has been assessed using GIS-based DRASTIC model by incorporating the major geological and hydrogeological factors that affect and control the groundwater contamination in a granitic terrain. It provides a relative indication of aquifer vulnerability to the contamination. Further, it has been cross-verified with hydrochemical signatures such as total dissolved solids (TDS), \(\hbox {Cl}^{-},\, \hbox {HCO}_{3}^{-},\, \hbox {SO}_{4}^{2-}\) and \(\hbox {Cl}^{-}/\hbox {HCO}_{3}^{-}\) molar ratios. The results show four zones of aquifer vulnerability (i.e., negligible, low, moderate and high) based on the variation of DRASTIC Vulnerability Index (DVI) between 39 and 132. About 57% area in the central part is found moderately and highly contaminated due to the 80 functional tannery disposals and is more prone to groundwater aquifer vulnerability. The high range values of TDS (2304–39,100 mg/l); \(\hbox {Na}^{+}\)(239– 6,046 mg/l) and \(\hbox {Cl}^{-}\) (532–13,652 mg/l) are well correlated with the observed high vulnerable zones. The values of \(\hbox {Cl}^{-}/\hbox {HCO}_{3}^{-}\) (molar ratios: 1.4–106.8) in the high vulnerable zone obviously indicate deterioration of the aquifer due to contamination. Further cumulative probability distributions of these parameters indicate several threshold values which are able to demarcate the diverse vulnerability zones in granitic terrain. 相似文献
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Ahmed H. Ahmed Shoji Arai Yaser M. Abdel-Aziz Moha Ikenne Abdellatif Rahimi 《Journal of African Earth Sciences》2009,55(1-2):92
The distribution of platinum-group elements (PGEs), together with spinel composition, of podiform chromitites and serpentinized peridotites were examined to elucidate the nature of the upper mantle of the Neoproterozoic Bou Azzer ophiolite, Anti-Atlas, Morocco. The mantle section is dominated by harzburgite with less abundant dunite. Chromitite pods are also found as small lenses not exceeding a few meters in size. Almost all primary silicates have been altered, and chromian spinel is the only primary mineral that survived alteration. Chromian spinel of chromitites is less affected by hydrothermal alteration than that of mantle peridotites. All chromitite samples of the Bou Azzer ophiolite display a steep negative slope of PGE spidergrams, being enriched in Os, Ir and Ru, and extremely depleted in Pt and Pd. Harzburgites and dunites usually have intermediate to low PGE contents showing more or less unfractionated PGE patterns with conspicuous positive anomalies of Ru and Rh. Two types of magnetite veins in serpentinized peridotite, type I (fibrous) and type II (octahedral), have relatively low PGE contents, displaying a generally positive slope from Os to Pd in the former type, and positive slope from Os to Rh then negative from Rh to Pd in the latter type. These magnetite patterns demonstrate their early and late hydrothermal origin, respectively. Chromian spinel composition of chromitites, dunites and harzburgites reflects their highly depleted nature with little variations; the Cr# is, on average, 0.71, 0.68 and 0.71, respectively. The TiO2 content is extremely low in chromian spinels, <0.10, of all rock types. The strong PGE fractionation of podiform chromitites and the high-Cr, low-Ti character of spinel of all rock types imply that the chromitites of the Bou Azzer ophiolite were formed either from a high-degree partial melting of primitive mantle, or from melting of already depleted mantle peridotites. This kind of melting is most easily accomplished in the supra-subduction zone environment, indicating a genetic link with supra-subduction zone magma, such as high-Mg andesite or arc tholeiite. This is a general feature in the Neoproterozoic upper mantle. 相似文献
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AbstractThe multi-layered Jeffara de Gabes aquifer system is greatly influenced by tectonics. This system is limited at the base and laterally by evaporite layers and has lateral contacts with the sebkhas (salt flats). The groundwater in this aquifer is characterized by high salinity (3–10 g L-1). Multivariate statistical analysis and a geochemical approach were applied to determine the influence of the evaporite layers and sebkhas on the hydrochemical quality of the Jeffara de Gabes aquifer, and to understand the processes governing its salinity. According to these methods, and based in part on the Sr2+/Ca2+ ratio, it is demonstrated that the strong salinity of the groundwater is due to interactions between water and the evaporite layers that act as a substratum of this aquifer, as well as saltwater intrusion from the sebkhas. Moreover, the medium- to poor-quality groundwaters are characterized by geochemical interactions: cationic exchange and the precipitation/dissolution process of minerals in the aquifer formations.Editeur Z.W. KundzewiczCitation Ben Alaya, M., Zemni, T., Mamou, A. et Zargouni, F., 2014. Acquisition de salinité et qualité des eaux d’une nappe profonde, Tunisie: approche statistique et géochimique. Hydrological Sciences Journal, 59 (2), 395–419. 相似文献
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Ahmed Mahmood 《国际地球制图》2013,28(2):91-101
In the case of a major disaster, information derived from satellite observation is not only highly useful, it may at times be indispensable because of the damage caused by the disaster to ground infrastructure. The International Charter ‘Space and Major Disasters’ (‘the Charter’) has been one of the primary sources of satellite data for the past 11 years to cover events like floods, fires, tsunamis, ocean storms, earthquakes, volcanic eruptions and oil spills. With the growing membership of the Charter, an increasingly large number of sensors are now available, which can be planned with the required temporal frequency and spectral range to cover a disaster event. Some of the type Charter activation cases are reported in this article to demonstrate the innovative use of multi-satellite imagery for disaster response. 相似文献
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Theoretical and Applied Climatology - Gridded precipitation products are becoming good alternative data sources for regions with limited weather gauging stations. In this study, four climate... 相似文献