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1.
Sidali Kourdali Nabila Bounakous Abdellah Meknachi Bilal Zenati Ahmed Inal 《Ocean Science Journal》2020,55(4):521-536
Ocean Science Journal - Biological monitoring has become one of the most widely used approaches in aquatic monitoring. As a result, the effect of the xenobiotics entrained by the organic and... 相似文献
2.
Transport and deposition of suspended particles in saturated porous media: hydrodynamic effect 总被引:1,自引:1,他引:1
Nasre-Dine Ahfir Hua Qing Wang Ahmed Benamar Adbellah Alem Nicolas Massei Jean-Paul Dupont 《Hydrogeology Journal》2007,15(4):659-668
A laboratory study was undertaken to determine the transport and deposition rate of suspended particles in columns of saturated porous media (gravel and glass beads), where the porous media were subjected to steady-state flow. Silt particles with a mode of 14 μm diameter (used as the suspended particles) and fluorescein (as the conservative tracer) were injected into the columns in short pulses. The breakthrough curves were competently described with the analytical solution of a convection–dispersion equation with a first-order deposition rate. The experiments were performed using different flow rates. The suspended particle size distribution, the porous media, and the flow rates themselves were the main factors retained in this study to investigate the mechanisms governing the transport and deposition kinetics in detail. The results showed the existence of a flow rate, beyond which suspended particles travel faster than the conservative tracer. A decrease of the deposition rate of suspended particles beyond a critical flow velocity was also observed. Such behaviour led to consideration of the couple hydrodynamic-gravity forces at high flow rates. As the hydrodynamic force increases, particle deposition rates are reduced due to the effect of hydrodynamic forces inhibiting the deposition. 相似文献
3.
Abdelouhed Farah Ahmed Algouti Abdellah Algouti Mohammed Ifkirne Zouhair Ourhzif 《Natural Hazards》2022,111(2):1907-1929
Natural Hazards - The present work focuses on using remote sensing techniques and geographical information system (GIS) to automatically extract lineaments in the southeast of Morocco, which is one... 相似文献
4.
Omar Elahcene Abdelali Terfous Boualem Remini Abdellah Ghenaim Jean-Bernard Poulet 《水文科学杂志》2013,58(1):224-236
Abstract Suspended sediment dynamics influenced by rainstorms and factors controlling changes in suspended sediment concentrations, were investigated during hydrological events in a small scale, since small agricultural drainage basins can be considered as one of the most important sediment sources. Suspended sediment concentrations were measured during discharge waves in the years 1987–1990, 1992, 2000 and 2001. Positive and anti-clockwise hysteresis was observed at Rybárik basin. A procedure of isolating factors controlling suspended sediment concentrations and dynamics has given a more realistic view on production and transport of suspended sediment. It is confirmed that spatial and temporal variability of sediment availability and suspended sediment dilution by the baseflow, mainly in the case of two or more waves immediately following one after another, significantly control suspended sediment concentrations and dynamics. 相似文献
5.
Ghizlane?BouskriEmail author Mohammed?Elabbassi Abdellah?Ammar Driss?El Ouai Mimoun?Harnafi 《Arabian Journal of Geosciences》2016,9(15):666
The study of 1000-km seismic reflection profiles, along the Northern Moroccan margin, allowed browsing new imaging in detail about the regional geological structures and their functioning. To achieve this goal, we elaborated a high-resolution depth model and a global tectonic sketch. The influence of recent tectonic activity is manifested by normal and strike-slip faults, trending mainly 70° N and 125° N. In this segment, the Nekor strike-slip fault seems to be connected to a secondary major fault system that changes direction from 30° N to 70° N, and changing behavior to left-lateral strike-slip fault with normal component. Analysis of local seismic activity recorded from 1990 to 2014 with moderate magnitudes activity shows alignments in clear superposition with the detected active faults in seismic reflection lines. 相似文献
6.
Ferran Estrada Gemma Ercilla Christian Gorini Bel��n Alonso Juan Tom��s V��zquez Daniel Garc��a-Castellanos Carmen Juan Andr��s Maldonado Abdellah Ammar Mohammed Elabbassi 《Geo-Marine Letters》2011,31(5-6):361-376
The study of more than 500 single- and multichannel seismic records enabled the generation of a detailed palaeo-bathymetric map of the Messinian surface over most of the Alboran Basin, Western Mediterranean. This regional surface is characterized by several erosional features (channels, terraces and canyons) and topographic highs (structural, volcanic and diapiric in origin). The most prominent feature is the incised Zanclean Channel crossing the entire basin, its entrenchment having been associated with the opening of the Strait of Gibraltar and subsequent inflow of Atlantic waters. The incision depth of the channel is variable, suggesting local variations in the erosive capacity of the Atlantic inflow, conditioned mainly by the regional basin topography and the local presence of topographic highs. Adjacent to this channel along the Spanish and Moroccan margins, and near the Strait of Gibraltar, several submarine terraces developed at different depths suggest a pulsed flooding of the Alboran Basin. There could have been two major inflow phases of Atlantic water, one shortly before and another during the Zanclean flooding, the latter accompanied by periods of relative sea-level stillstands that enabled terrace development. Alternatively, these features were all generated during the main flooding evident and subsequent pulsed infilling of the basin. 相似文献
7.
Wael R. Abdellah Haitham M. Ahmed Mohammed A. Hefni 《Geomechanics and Geoengineering》2019,14(1):41-51
Stope stability is a key factor for the success of a mining operation. To optimise ore productivity while maintaining stope stability, the mining block/stope must be extracted in stages. Ore dilution will occur if the stope is not properly excavated/blasted. This study examines stope stability during mining in three stages, where the height of each stage stope is 10 m. The paper also presents simulation analysis of a typical steeply dipping tabular orebody at 1200 m depth below the surface, which is common in many Canadian underground hard rock mines. Numerical modelling analysis was conducted using the finite element program, RS2D, where the non-linear elasto-plastic Mohr-Coulomb failure criterion was adopted. The rock reinforcement system (i.e. cable bolts) was modelled/installed in the stope footwall after each mining stage to strengthen access drifts and stabilise the rock mass around the stope that was disturbed by mining activity. Results are discussed in terms of depth of failure zones, total deformation and axial forces in cable bolts with respect to mining stage. 相似文献
8.
Bianca Alves de Souza Igor da Silva Rocha Paz Abdellah Ichiba Bernard Willinger Auguste Gires Jose Carlos Cesar Amorim 《水文科学杂志》2013,58(11):1619-1635
ABSTRACTThe spread of impervious surfaces in urban areas combined with the rise in the intensity of rainfall events as a result of climate change has led to dangerous increases in storm water flows. This paper discusses a new implementation of the fully distributed hydrological model Multi-Hydro (developed at École des Ponts ParisTech), when operating storage basins, and its ability to deal with high-resolution radar rainfall data. The peri-urban area of Massy (south of Paris, France) was selected as a case study for having six of these drainage facilities, used extensively in flood control. Two radar rainfall datasets with different spatiotemporal resolutions were used: Météo-France’s PANTHER rainfall product (C-band) and ENPC’s X-band DPSRI. The rainfall spatiotemporal variability was analysed statistically using Universal Multifractals (UM). Finally, to validate the application, the water level simulations were compared with local measurements in the Cora storage basin located next to the catchment’s single outlet. 相似文献
9.
Ahmed Benamar HuaQing Wang Nasre-dine Ahfir Abdellah Alem Nicolas Masséi Jean-Paul Dupont 《Comptes Rendus Geoscience》2005,337(5):497-504
We study in this paper the transport and deposition of suspended particles in saturated porous media. Some chromatographic short-pulse tests were performed in a laboratory column with a tracer and two types of suspended particles. A mathematical model was used to determine the hydrodispersive parameters and deposition rates from the breakthrough curves. The results show that the fitted parameters obtained vary with the flow rate and the characteristics of the suspended particles. We also observe, at high flow rates, that particles have a migration velocity higher than that of the conservative tracer. To cite this article: A. Benamar et al., C. R. Geoscience 337 (2005). 相似文献
10.
Georges Kesserwani Rabih Ghostine José Vazquez Robert Mosé Maher Abdallah Abdellah Ghenaim 《Advances in water resources》2008
The spectrum of this survey turns on the evaluation of various existing theoretical combining models, when invoked within the internal boundary condition management at a junction. Based on the assumption that: when the Froude number is low (i.e. the flow is subcritical), the energy equation at the junction can be approximated by the stages heads equality. Actual literature and many commercial packages rather use this concept for the treatment of the junction’s internal boundary handling because it is easy to implement and it avoids the solving of nonlinear equations. In the last decade, many nonlinear combining models, based on the momentum conservation through the junction, have been reported. However, using them to operate within the internal boundary condition treatment of an open-channel confluence has not yet been investigated. Hence, this research focuses on studying the practical aspect of several combining models, once applied within the junction’s internal boundary management. Therefore, the recent nonlinear models of Gurram, Hsu and Shabayek have been briefly detailed together with the traditional concept of assuming water stages equality at the junction. Subsequently, an experimental examination was performed according to available experiments as mean to pre-evaluate (separately at the junction) the four junction models in the steady state. Moreover, according to the latter inspection the attention was constrained to study the effect of high/low subcritical Froude number at the junction. Finally, two hypothetical hydraulic problems were defined and computed in order to exhibit the performance of these junction models when used to contend the junction’s internal boundary handling. The problems involved: (a) steady and transient flows; (b) high and low (subcritical) Froude number at the junction. Supported by the experimental and numerical investigations, it can be concluded that even while the Froude number spectrum is subcritical, precautions have to be taken when dealing with the concept of energy heads equality, notably for a Froude higher than 0.35 at the junction. 相似文献