Geological evolution of Nile Valley,west Sohag,Upper Egypt: a geotechnical perception     

El-Sayed Sedek Abu Seif 《Arabian Journal of Geosciences》2015,8(12):11049-11072

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Fertile Lithospheric Mantle Beneath the North African Plate: Evidence from Gharyan Lherzolite Xenoliths (Northern West Libya)     

Mohamed M. Hamdy  Youngwoo Kil  Hassan Abu Arabia 《Petrology》2018,26(5):546-563

The late-stage basanite (～12–1 Ma) of the NNW-SSE extending Gharyan Cenozoic volcanics (Northern West Libya) contains numerous fresh lherzolite xenoliths. These xenoliths display magmatic protogranular and porphyroclastic textures. Chemistry of olivine (forsterite content –90–91, NiO = 0.26–0.39 wt %), orthopyroxene (Mg# = 0.91–0.92, Cr# = 0.03–0.07, Al₂O₃ = 3.64–4.43 wt %), clinopyroxene ((Wo_{45.59–48.61}, En_{45.89–48.80}, Fs_4.47–5.81), Mg# = 0.82–0.92, Al₂O₃ = 5.14–6.58 wt % and Cr₂O₃ = 0.5–0.95 wt %) and spinel (hercynite–picotite–Al-rich chromite spinels with Cr# = 0.08–0.11) refer to the fertile nature of Gharyan peridotites. Mantle source region was close to the primitive composition with low degrees of melting and depletion in melt (1.5% in average). However, it underwent metasomatism as illustrated by formation of secondary clinopyroxene (Wo_{37.96–44.77}, En_{47.44–54.18}, Fs_7.59–8.03) with high contents of Na₂O, and enrichment of the Al-spinel in TiO₂. The estimated pre-eruptive temperature ranges from 1066 to 837°C. Despite the Gharyan peridotite is similar to mantle components in many districts in Saharan belt of North Africa, it represents juvenile mantle source with minor refractory residues. This compositional heterogeneity is mainly attributed to the local effect of the interaction of the Gharyan mantle with the host basanite magma that may be related to the Cenozoic rifting of the Pan-African basement.  相似文献   

Hunza river watershed landslide and related features inventory mapping     

M. Farooq Ahmed  J. David Rogers  Muhammad Zubair Abu Bakar 《Environmental Earth Sciences》2016,75(6):523

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Subsurface profile interpretation of landslides,examples from Bashilo River watershed,Ethiopia     

Elamin H. Ismail  J. David Rogers  M. Farooq Ahmed  M. Zubair Abu Bakar 《Environmental Earth Sciences》2016,75(16):1153

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Development of calcrete of the Late Cretaceous carbonate platform,northern Jordan,and its tectonic implications     

Abdulkader M. Abed  Saja Abu Taha  Tasneem H. Hiasat  Abdalla Abu Hamad 《Arabian Journal of Geosciences》2016,9(11):587

A calcrete horizon, 3–10 m thick, is found exposed in northern Jordan in three localities, Rumman, Marsa’, and Wasfi At Tal forest (WTF). It is situated at the base of the dominantly limestone, Late Cenomanian Hummar Formation, separating it from the underlying marly Fuheis Formation. The calcrete horizon exhibits all the diagnostic features characteristic of calcrete, such as diagenetic pisoids; a mottled or clotted texture; circumgranular cracks around grains in a nodular texture; pendant or microstalactitic cement; meniscus cement; plant roots or rhizogenic structures, both longitudinal and transverse; exfoliation on boulder and cobbles; alagally laminated hard pans; and abundant dissolution of cracks and vugs. Consequently, it represents a subaerial erosional unconformity and type 1 sequence boundary (SB) that was not previously noticed. The Hummar Formation is considered as a third-order sequence with the SB at the base of the calcrete horizon, while the calcrete horizon itself forms the lowstand system tracts (LST). The transgressive systems tracts (TST) involve the lower two third of the Hummar Formation ending with peloidal grainstone representing the maximum flooding surface (MFSs). The rest of the formation is the falling highstand systems tracts (HST). The next SB is not seen due to a thick soil-covered gap. The calcrete horizon formed due to the formation of a paleohigh, in the study area, associated with the compression produced by the initial subduction of the Afro-Arabian Plate under the Eurasian Plate during the Late Cenomanian, slightly earlier than the previously known Turonian subduction and compression.  相似文献   

Multivariate and principal component statistical analysis of contamination in urban and agricultural soils from north Jordan   总被引：1，自引：0，他引：1  

S. R. Salman  Y. H. Abu Ruka'h 《Environmental Geology》1999,38(3):265-270

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Chitosan – A Sizing Agent in Fabric Production – Development and Ecological Evaluation     

Thomas Stegmaier  Werner Wunderlich  Tom Hager  Abu Bakr Siddique  J. Sarsour  Heinrich Planck 《洁净——土壤、空气、水》2008,36(3):279-286

Chitosan, a natural polymer, was investigated as a possible sizing agent in fabric production by appropriate modification in the textile industry. Based on recipe developments at a laboratory‐scale, the ecological and economical potential of mainly cotton yarns were demonstrated and developed. Subsequent tests within the scope of industrial production confirmed the findings of the basic developments. As an interesting alternative to the conventional sizing process involving the removal of the size after weaving, the use of appropriate processing technologies makes it possible to apply chitosan in the form of a sizing agent resistant to wash‐out processes. Therefore, the wash‐out process and the combined wastewater loading can be avoided and the properties of chitosan can be used beneficially in the later applications of the fabric. The traditional method of sizing and weaving developments as well as the analyses of material recycling showed the possibilities of using closed circuits in textile production involving sizing agent and water. It is possible that a chitosan‐specific enzyme suitable for production conditions, which facilitates the wash‐out process in combination with the biodegradation of the wastewater in a sewage plant, could be developed.  相似文献   

Untapped Economic Resource Potential of the Neoproterozoic to Early Paleozoic Volta Basin,Ghana: A Review     

Abu  Mahamuda  Sunkari  Emmanuel Daanoba  Şener  Mehmet 《Natural Resources Research》2019,28(4):1429-1445

Natural Resources Research - The ~?115,000 km2 Volta Basin of Ghana is one of the most studied geological terrains. However, unlike the Birimian and Tarkwaian which have been...  相似文献   

南海中尺度涡温盐结构的季节特征及形成机制   总被引：2，自引：0，他引：2  

祖永灿  孙双文  赵玮  李培良  刘宝超  方越  Samah Azizan Abu 《海洋学报(英文版)》2019,38(4):29-38

本文利用最新的涡旋数据集和ARMOR3D数据，研究了南海中尺度涡温盐结构的季节特征及形成机制。合成分析的结果表明，在冬季，涡旋引起温度异常的水平分布在50米以浅表现为类似偶极型分布，而在50m以深则趋向于中心对称分布；在夏季，温度异常的水平分布均表现为中心对称的特征。涡旋引起盐度异常的水平分布也具有类似的季节特征，但是偶极型中的不对称性相对较弱。在垂向上，涡旋所致的温度异常表现为单层结构，而盐度异常则为三层结构。进一步的分析表明，涡旋所致温盐异常的垂向分布特征与背景温盐的垂向分层有关；而在50m以浅，温盐异常的水平分布的不对称特征主要由背景温盐场的水平平流所致。  相似文献   

Correction to: Perceived and actual risks of drought: household and expert views from the lower Teesta River Basin of northern Bangladesh     

Salam  Roquia  Ghose  Bonosri  Shill  Badhon Kumar  Islam  Md. Aminul  Islam  Abu Reza Md. Towfiqul  Sattar  Md. Abdus  Alam  G. M. Monirul  Ahmed  Bayes 《Natural Hazards》2021,108(3):2589-2589

Natural Hazards - A correction to this paper has been published: https://doi.org/10.1007/s11069-021-04825-3  相似文献