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311.
Sattam Almadani Hussain Alfaifi Abdullah Al-Amri Mohamed Fnais Elkhedr Ibrahim Kamal Abdelrahman Mohammed Shehata Faisal Zaidi 《Arabian Journal of Geosciences》2017,10(6):139
This study was carried out in the Alwadeen area of Khamis Mushayt district of southwestern Saudi Arabia to evaluate the hydrochemical characteristics of the shallow hard rock aquifers. These hard rock aquifers mostly comprise granites and contain significant quantities of groundwater that complement the available groundwater from the unconsolidated alluvial sediments in the nearby wadis. The field investigation indicates two main fracture sets which intersect each other and are oriented in the west-northwest and east-west directions. The granitic rocks in the area are intruded by coarse-grained and quartz-rich monzogranite and pegmatite veins. Hydrogeologically, the fracture systems are important since they facilitate the groundwater storage and assume the transmissive function during times of groundwater abstraction. Given the fact that groundwater in the fractured rock aquifers generally occurs at shallow depths, it may be exposed to contamination from surface and/or near-surface sources, and it is therefore important to evaluate its quality. To this end, a hydrochemical analysis was carried out on six groundwater samples collected from the area. The hydrochemistry revealed that the groundwater is fairly fresh, and facies analysis reveals mixed Na-Cl and Ca-Mg-Cl-SO4 types. Overall, the results reveal that the groundwater is saturated with calcite and dolomite, but unsaturated with gypsum and halite. The degree of salinity increases in the direction of the groundwater flow due to increased rock-water interaction. 相似文献
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Ohne Zusammenfassung 相似文献
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316.
Physical and chemical characterization of spent oil shale (OS) from El-Lajjun area has been carried out and compared with
the original OS. The spent shale (SS) is subjected to leaching tests to detect the possibilities of heavy metals released
from it into the environment. Standard column leaching experiments have revealed no detectable release of heavy metals to
the percolating water. The effectiveness of the SS in removing Pb2+ from wastewater has been investigated. The SS is very efficient in removing most of Pb2+ where 1 m3 of SS has an efficiency to remove from 64 to 94% of Pb2+ from about 1,300 m3 wastewater sample containing 50 ppm Pb2+. The efficiency decreases substantially with increasing Pb2+ concentration in the wastewater. In real situations, where Pb2+ concentration is very low (i.e., less than 5 ppm), the efficiency of the SS is expected to be 100%. 相似文献
317.
Salam Roquia Islam Abu Reza Md. Towfiqul Shill Badhon Kumar Alam G. M. Monirul Hasanuzzaman Md. Hasan Md. Morshadul Ibrahim Sobhy M. Shouse Roger C. 《Natural Hazards》2021,106(1):529-529
Natural Hazards - The article was published with a spelling error in one of the co-author names. The correct spelling is reflected in this correction, and the original work has been updated to... 相似文献
318.
Syed Ibrahim Wahab Uddin Bhuwan Joshi Ramesh Chandra Arun Kumar Awasthi 《天文和天体物理学研究(英文版)》2021,(12):235-253
In this article,we compare the properties of two coronal mass ejections(CMEs)that show similar source region characteristics but different evolutionary behavior... 相似文献
319.
Metavolcanic rocks hosting base metal sulphide mineralization, and belonging to the Kid
Metamorphic Complex, are exposed in the Samra-Tarr area, Southern Sinai. The rocks consist of slightly
metamorphosed varicolored porphyritic lavas of rhyolite-to-andesite composition, and their equivalent
pyroclastics. Geochemically, these metavolcanics are classified as high-K calc-alkaline, metaluminous
andesites, trachyandesites, dacites, and rhyolites. The geochemical characteristics of these metavolcanics
strongly point to their derivation from continental crust in an active continental margin. The sulphide
mineralization in these metavolcanics occurs in two major ore zones, and is represented by four distinct
styles of mineralization. The mineralization occurs either as low-grade disseminations or as small
massive pockets. The associated hydrothermal alterations include carbonatization, silicification, sericitization
and argillic alterations. The base metal sulphide mineralization is epigenetic and was formed by
hydrothermal solutions associated with subduction-related volcanic activity. 相似文献
320.
Acta Geochimica - The present study deals with the detailed field geology, mineralogy, geochemistry, and spectrometric prospection of rare metals and radioactive minerals associated with granitic... 相似文献