On the development of a seismic source zonation model for seismic hazard assessment in western Saudi Arabia   总被引：1，自引：0，他引：1  

Hani M. Zahran  Vladimir Sokolov  M. John Roobol  Ian C. F. Stewart  Salah El-Hadidy Youssef  Mahmoud El-Hadidy 《Journal of Seismology》2016,20(3):747-769

A new seismic source model has been developed for the western part of the Arabian Peninsula, which has experienced considerable earthquake activity in the historical past and in recent times. The data used for the model include an up-to-date seismic catalog, results of recent studies of Cenozoic faulting in the area, aeromagnetic anomaly and gravity maps, geological maps, and miscellaneous information on volcanic activity. The model includes 18 zones ranging along the Red Sea and the Arabian Peninsula from the Gulf of Aqaba and the Dead Sea in the north to the Gulf of Aden in the south. The seismic source model developed in this study may be considered as one of the basic branches in a logic tree approach for seismic hazard assessment in Saudi Arabia and adjacent territories.  相似文献   

Re-evaluation and updating of the seismic hazard of Lebanon     

Carla Huijer  Mohamed Harajli  Salah Sadek 《Journal of Seismology》2016,20(1):233-250

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Road traffic nanoparticle characteristics:Sustainable environment and mobility     

Ines Belkacem  Ali Helali  Salah Khardi  Amani Chrouda  Khalifa Slimi 《地学前缘(英文版)》2022,(1):388-403

Human effects and environment impacts associated with nanoparticles generated from road traffic have recently attracted wide attention.Knowledge of the influencing variables on both number and mass of nanoparticles,sources,characteristics and limitations of advanced commercially accessible instruments for monitoring nanoparticles,are still scarce and not sufficient to make regulatory decision on solid particles smaller than 23 nm(SPN<23 nm).Given the harmful effects of nanoparticles on human health(i.e.visibility impairment,cardiac-rhythm disturbance,heart attacks,premature death,etc.),their control and assessment seem to be an absolute priority.In this overview,we classify and analyze the existing knowledge of nanoparticles in road traffic atmosphere,recent progress,and emerging priorities in research related to these topics.The major aspects of ongoing research in this field,and a brief discussion of the main sources of atmosphere nanoparticles are presented.The subsequent section focuses on the influencing parameters of nanoparticles including climate conditions,height above the road surface and distance between source(road traffic)and sampling site.The next section provides a comprehensive summary on sampling measurement methodologies and instrumental techniques.We also review the health and environment implications associated with particle exposure.Finally,an evaluation of the state of research related to nanoparticles together with highlights for future research activities are also presented.  相似文献   

Acidic Rocks as Aggregates in Concrete: Engineering Properties,Microstructures and Petrologic Characteristics     

A. I. M. Ismail  D. Sadek Ghabrial 《Geotechnical and Geological Engineering》2009,27(4):519-528

In this research, the possibility of replacing different portions of the normally used aggregate by acidic rocks was investigated. These rock types outcrop at the northern part of Eastern Desert, southwest Ras Gharib area where large quantities of good quality acidic rocks are available their. Portland cement concrete is a composite material made up of the hydrated cement matrix, fine aggregate and coarse aggregate. The scanning electron microscope equipped with an energy dispersive X-ray analysis system (EDX) has been applied to investigate several aspects of Portland cement concrete microstructure. The topics investigated so far include the influence of aggregate composition on the development of the cement paste-aggregate interface and the formation of calcium silicate hydrate CSH/calcium silicate aluminate CSA formation. The silicate gel coated the aggregates in the concrete paste and crystallized into well defined needle like shape, cotton shape as well as euhedral to subhedral crystals of silicate/alumiante and ettringite minerals with free lime librated from the hydrolysis process. The free lime can react again with the aggregates leading to the formation of cementing materials which increase strength and durability of the concrete paste by increasing the interfacial bonds between the used aggregates.  相似文献   

陶瓷工业中对产自花岗岩的长石原料的提纯方法研究     

Mohamed El-Omla  Salah Shata 《地质与资源》2008,17(3):235-240

花岗岩是陶瓷工业中所需长石原料的重要来源之一.由于花岗岩中云母和氧化铁的存在,其最终产品的质量受到影响（强度、硬度、密度降低）.本研究对浙江花岗岩采用两阶段分离方法,以提高花岗岩中长石的质量.第一阶段为重力分离,去除重矿物杂质;第二阶段为磁性分离,进一步减少铁含量.用机械方法对不同加工阶段的3种样品进行了成分测试：1）原料花岗岩;2）第一阶段处理的花岗岩;3）第二阶段处理的花岗岩.结果显示,最终处理后的样品较之原始花岗岩在显微硬度、强度、密度及裂隙坚韧性方面都有明显提高.  相似文献   

A static axisymmetric anisotropic fluid solution in general relativity     

Salah Haggag 《Astrophysics and Space Science》1990,173(1):47-51

Einstein's interior field equations in general relativity are considered when spacetime is static and axisymmetric and the energy-momentum tensor represents an anisotropic fluid. After imposing a set of simplifying assumptions a two-parameter solution is derived and its properties are discussed. The solution is found to be physically reasonable in a certain range of the parameters in which case the metric could represent a core of anisotropic matter.  相似文献   

南京地质环境的基本特征和几个主要环境岩土工程问题   总被引：19，自引：2，他引：17  

罗国煜  张晓昭 《高校地质学报》1998,4(2):189-197

环境问题已成为全球热点,本文提出了关于人类社会面临的两类环境问题的概念,即污染和生态破坏及环境岩土工程问题,论述了南京市的地质环境特点,剖析了南京市的几个主要环境岩土工程问题。这对深化环境问题的认识,促进南京经济建设的发展,推动南京环境岩土工程问题瓣研究有积极意义。  相似文献   

Experimental Investigation of Frictional Behavior Between Cohesive Soils and Solid Materials Using Direct Shear Apparatus     

Marwa Feligha  Farid Hammoud  Mouloud Belachia  Mohamed Salah Nouaouria 《Geotechnical and Geological Engineering》2016,34(2):567-578

Soil shearing resistance is very important while designing various structures which have direct contact with soil, for example, sheet piles, piles, retaining walls, reinforced earth structures and shallow foundations. Even though designers use empirical values for their design, it is very important to obtain more accurate values for soil–solid materials shearing resistance. In this work, laboratory tests have been carried out to investigate the effect of roughness interface and texture models on friction angle between cohesive soils and steel, as well as abrasive paper material, using direct shear tests. All tests were carried out under consolidated drained shear conditions. The behavior at the soils–solid interface was found to vary according to surface roughness. It also seems that the type of material (steel or paper of abrasive) used does not have a major influence on the shear strength. As far as roughness is concerned, friction behavior is likely to be generally classified into three failure modes, namely full sliding at the interface, shear failure within the soil, and a mixed behavior where interface sliding and shear deformation of the soil specimen proceed simultaneously. However, for the second mode, the shear strength at the interface soil-rough solid materials steel was found to be lower than the shear strength of the soil, for a soil that is classified as high plasticity clay. Furthermore, it was found that the interfacial shear strength is independent of the texture surface for a given roughness.  相似文献   

A salt diapir-related Mississippi Valley-type deposit: the Bou Jaber Pb-Zn-Ba-F deposit,Tunisia: fluid inclusion and isotope study     

Salah Bouhlel  David L. Leach  Craig A. Johnson  Erin Marsh  Sihem Salmi-Laouar  David A. Banks 《Mineralium Deposita》2016,51(6):749-780

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Runoff and sediment yield modeling using SWAT model: case of Wadi Hatab basin,central Tunisia   总被引：1，自引：0，他引：1  

Narjes Chaâbane Ben Salah  Habib Abida 《Arabian Journal of Geosciences》2016,9(11):579

This study presents an application of the model Soil and Water Assessment Tool (SWAT) to simulate daily and monthly water flow and sediment fluxes in the Wadi Hatab watershed (2200 km²) located in central Tunisia. The study basin is characterized by a significant climatic contrast, abrupt topography, and soil fragility, resulting thereby in flash floods and important water erosion rates. This alarming situation requires urgent interventions in order to preserve water and soil resources, implying the need for a decision tool for proper integrated management of the watershed. The model was calibrated and validated based on a comparison of simulated and observed flow rates at the basin outlet (hydrometric station Khanguet Zazia), during the periods 1987–1988 and 1989–1990, respectively. The comparison was based not only on visual inspection of the agreement between observed and simulated time series, but also on statistical parameters. Indeed, for the daily time step application, the Nash—Sutcliffe efficiency (NSE) values were 0.52 and 0.61, and the coefficient of determination (R²) was 0.54 and 0.61 for calibration and validation, respectively. As for the monthly time-step application, the obtained NSE values were 0.67 and 0.89 while R² values were 0.83 and 0.87 for calibration and validation, respectively. This clearly shows the reasonably good agreement between simulated and observed flow rates. In terms of erosion, the model gave sediment yield values ??of 1.15 and 5.37 t/ha/year during the periods of calibration and validation, respectively.  相似文献