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Groundwater is an important water resource in the Helwan area, not only for drinking and agricultural purposes, but also because
several famous mineral springs have their origin in the fractured carbonate aquifer of the region. The area is heavily populated
with a high density of industrial activities which may pose a risk for groundwater and surface water resources. The groundwater
and surface water quality was investigated as a basis for more future investigations. The results revealed highly variable
water hydrochemistry. High values of chloride, sulphate, hardness and significant mineralization were detected under the industrial
and high-density urban areas. High nitrate contents in the groundwater recorded in the southern part of the study area are
probably due to irrigation and sewage infiltrations from the sewage treatment station. The presence of shale and marl intercalation
within the fissured and cavernous limestone aquifer promotes the exchange reactions and dissolution processes. The groundwater
type is sodium, sulphate, chloride reflecting more mineralized than surface water. The results also showed that water in the
study area (except the Nile water) is unsuitable for drinking purposes, but it can be used for irrigation and industrial purposes
with some restrictions. 相似文献
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Mabrouk SAMI Theodoros NTAFLOS Haroun A. MOHAMED Esam S. FARAHAT Christoph HAUZENBERGER Nasser M. MAHDY Khaled M. ABDELFADIL Douaa FATHY 《《地质学报》英文版》2020,94(3):763-776
A highly-fractionated garnet-bearing muscovite granite represents the marginal granitic facies of the Abu-Diab multiphase pluton in the Central Eastern Desert of Egypt. New electron microprobe analyses(EMPA) and laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS) data from garnets are reported, in order to constrain their origin and genesis. Garnet in the Abu-Diab host granite is euhedral to subhedral, generally homogeneous and, in rare cases, it shows weak zonation. The garnet contains appreciable amounts of MnO and FeO, with lesser amounts of MgO and CaO, yielding an end-member formula of Sps_(61–72)Alm_(25–35)Prp_(1–4)Adr_(0–1). Moreover, it is depleted in large ion lithophile elements(LILE) with lower values of Ba, Nb and Sr relative to the primitive mantle. Additionally, it contains high concentrations of HREE and Y and their REE pattern shows strong negative Eu anomalies. The garnet was crystallized under relatively low temperature(646°C–591°C) and pressure( 3 kbar) conditions. The textural and chemical features indicate that the garnet is magmatic in origin and is chemically similar to that from highly-fractionated A-type granite. It was probably formed at the expense of biotite in a highly-evolved MnO-rich magma and/or by hydroxyl complexing of Mn during the ascending fluid phases. 相似文献
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