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Malika Kili Bouabid El Mansouri Jamal Chao Abderrahman Ait Fora 《Comptes Rendus Geoscience》2006,338(16):1194-1202
The Rharb basin is located in northwestern Morocco. It is a part of one of the most important hydrogeological basins of Morocco, and extends over some 4000 km2. The nature of its Plio-Quaternary sedimentary fill and its structural and palaeoenvironmental contexts are reflected by great variations in aerial and temporal facies distribution. This distribution, in turn, is a direct cause of the observed complexity in the geometry of potentially water-bearing beds. In the present work, we present an image of potential new hydrogeological reservoirs and define new structures that partially explain their architecture. To cite this article: M. Kili et al., C. R. Geoscience 338 (2006). 相似文献
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Amal Saidi Abdelfatah Tahiri Lahcen Ait Brahim Maraim Saidi 《Comptes Rendus Geoscience》2002,334(3):221-226
The fracturing analysis in the Permian basins of Jebilet and Rehamna (Hercynian Morocco) and the underlying terranes allowed us to suggest a model for their opening. Three tectonic episodes are distinguished: a transtensional episode NNE–SSW-trending (Permian I), occurring during the opening along sinistral wrench faults N70–110-trending, associated with synsedimentary normal faults; a transpressive episode ESE–WNW-trending (Permian II), initiating the closure, the normal faults playing back reverse faults and the N70 trending faults dextral wrench faults; a compressional episode NNW–SSE (post-Permian, ante-Triassic), accentuating the closure and the deformation and putting an end to the Tardi-Hercynian compressive movements. To cite this article: A. Saidi et al., C. R. Geoscience 334 (2002) 221–226. 相似文献
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Rachid Ait Akbour Jamaâ Douch Mohamed Hamdani Philippe Schmitz 《Comptes Rendus Geoscience》2002,334(13):981-985
To evaluate the risk of contaminant transport by mobile colloids, it is necessary to understand how colloids and associated pollutants behave during their migration through uncontaminated soil or groundwater. In this study, we investigated the influence of aggregation induced by Ca2+ and trace metals (Pb2+, Cu2+) concentrations on the transport of humic-coated kaolinite colloids through a natural quartz sand at pH=4. Adsorbed divalent cations reduce the colloids surface charge and thereby induce aggregation and deposition in porous media. To cite this article: R. Ait Akbour et al., C. R. Geoscience 334 (2002) 981–985. 相似文献
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W.A. Abderrahman M. Rasheeduddin I.M. Al-Harazin M. Esuflebbe B.S. Eqnaibi 《Hydrogeology Journal》1995,3(4):32-41
Insufficient attention has been given to management issues of groundwater in desertic aquifers, especially pumping policies and the proper design of well fields, i.e., the spatial distribution among wells and among well fields. In Saudi Arabia, many wells have been drilled in small areas, and in some parts of the Kingdom, groundwater pumping has increased drastically during the last two decades. Heavy pumping from large numbers of clustered wells in closely spaced well fields has resulted in unacceptable impacts on water levels and water quality in these areas. Numerical techniques were used to assess the impacts of this practice in parts of the Eastern Province. If the existing water-management policies and trend of increased pumping continue, a considerable additional drawdown will occur. Therefore, proper groundwater-management and conservation schemes need to be adopted. The approaches include optimization of well-field designs and well operations, and the implementation of effective irrigation-scheduling techniques. The implementation of a comprehensive irrigation water-management system in a large irrigation project has resulted in significant recovery of groundwater in the project area in the Eastern Province. RÉSUMÉ: Trop peu d'attention a été accordée aux questions de gestion des eaux dans les aquifères désertiques, particulièrement en ce qui concerne la règlementation des pompages et le groupement judicieux des puits, i.e., la répartition en surface des puits et des champs de puits. En Arabie Saoudite, de nombreux puits ont été forés sur des surfaces réduites, et, dans certaines parties du Royaume, le pompage des eaux s'est accru de façon spectaculaire dans les deux dernières déciennes. Un pompage important à partir d'un grand nombre de puits concentrés dans des ensembles rapprochés les uns des autres a eu des effets inacceptables sur le niveau et la qualité des eaux. Des techniques d'analyse numériques ont été employées pour évaluer les conséquences de ces modes de gestion dans certaines parties de la Province de L'Est. Si l'actuelle gestion des eaux se poursuit et le pompage continue de croître, il en résultera un abaissement considérable du niveau d'eau. Il est donc nécessaire d'adopter dans ces régions des méthodes de gestion et de conservation appropriées. Ces méthodes consistent, entre autres, à optimiser l'agencement des groupements de puits et de l'opération des puits, ainsi qu'à adopter des techniques efficaces pour programmer les horaires d'irrigation. L'adoption d'un sytème intégré de gestion des eaux dans un grand programme d'irrigation a provoqué une remontée substantielle des eaux souterraines dans la partie de la Province de L'Est correspondant à la zone du projet. RESUMEN: Los problemas de gestión de las aguas subterráneas en acuíferos desérticos no han recibido suficiente atención, especialmente en lo que respecta a las políticas de captaciones y al diseño adecuado de los campos de pozos, es decir, la distribución espacial de los pozos y de los campos de pozos. En Arabia Saudita, muchos pozos se han excavado en áreas pequeñas, y en algunas partes del Reino, el bombeo de agua se ha incrementado drásticamente durante las dos últimas décadas. El fuerte bombeo en un gran número de pozos de bombeo agrupados, situados en campos de extracción próximos, ha dado lugar impactos inaceptables en los niveles y en la calidad del agua en estas áreas. Se usaron técnicas numéricas para evaluar los impactos de esta política de extracción en partes de la Provincia Oriental. Si la política de gestión del agua actual y el incremento en el bombeo se mantienen, darán lugar a un descenso de niveles adicional considerable. Por tanto, en estas áreas es necesario adoptar esquemas apropiados de gestón y conservación de las aguas subterráneas. Esto incluiría la optimización de los diseños y de los criterios de operación de los campos de pozos y la adopción de técnicas de riego efectivas. La puesta en marcha de un sistema de gestión de aguas de riego, dentro de un gran proyecto de irrigación, ha dado como resultado una recuperación significativa de los niveles de agua en el área de proyecto, situada en la Provincia Oriental. 相似文献
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Weak dust acoustic (DA) solitary waves are investigated in a mixed nonthermal high energy-tail electron distribution, focusing on the influence of an interplay between nonthermality and superthermality on the DA soliton energy. It is shown that in a pure superthermal plasma (α=0), electron thermalization (κ→∞) leads to an increase of the energy carried by the soliton. Addition of minute quantities of nonthermal electrons drastically modifies the κ-dependence of the soliton energy E κ,α . The latter first decreases, then exhibits a local minimum before leveling at a constant value. The energy exchange between the non-Maxwellian electrons and the localized solitary structure depends drastically on the interplay between superthermality and nonthermality. 相似文献
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The lower Mesozoic of the Traras mount starts with the so-called Red Series, which lays uncomformably on the folded and granitized Paleozoic basement. This series is overlain by Middle Liassic limestones. On the basis of its lower and upper limits and the lack of dating evidence, former authors attribute a Permian to lower Liassic (Sinemurian) age for this series. Palynological results allow to range it in the upper Triassic probably Norian-Rhetian. The Red Series is studied from five sections that depict important thickness and facies variations from southwest to the northeast, inferring the irregularities of the Hercynian erosional surface. In the Central Traras, this series shows over 130-m-thick micaceous sandy conglomeratic units, deposited within alluvial fans, where the bedrock source corresponds to granite of Nedroma or its equivalent. In the southern and eastern Traras, where the series’ thickness respectively does not exceed 30 m and averages 40–80 m, besides alluvial deposits issued from hercynian basement erosion, it exhibits volcanic evidences interbedded by lacustrine deposits. Vertical and spatial distribution depicts synsedimentary infilling of narrow elongated rift basins, typically half-grabens, bounded on one side by a normal fault or a series of normal faults trending NNE-SSW to NW-SE, inherited from the hercynian event. The study of tectonostratigraphic units permitted to put forward geodynamics of the infilling basins. 相似文献
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Al Yacoubi Latifa Bouchaou Lhoussaine Jaillard Etienne Masrour Moussa Ait Brahim Yassine El Mouden Ahmed Schneider Jana Reichert Barbara 《Arabian Journal of Geosciences》2017,10(7):169
The Agadir-Essaouira area in the occidental High Atlas Mountains of Morocco is characterized by a semi-arid climate. The scarcity and quality of water resources, exacerbated by long drought periods, constitute a major problem for a sustainable development of this region. Groundwater resources of carbonate units within Jurassic and Cretaceous aquifers are requested for drinking and irrigation purposes. In this study, we collected 84 samples from wells, boreholes, springs, and rivers. Hydrochemical and isotopic data were used to examine the mineralization and origin of water, which control groundwater quality. The chemical composition of water seems to be controlled by water-rock interactions, such as dissolution of carbonates (calcite and dolomite), weathering of gypsum, as well as ion exchange processes, which explain the observed variability. Stable isotopes results show that groundwater from the mainly marly Cretaceous aquifer are submitted to an evaporation effect, while samples from the chiefly calcareous Jurassic aquifer indicate a meteoric origin, due to a rapid infiltration of recharge runoff through the karstic outcrops. The low values of δ18O and δ2H suggest a local recharge from areas with elevations ranging from 400 to 1200 m for the Cretaceous aquifer and from 800 to 1500 m for the Jurassic units. 相似文献
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Arid to semi-arid regions are characterized by low levels of surface water and low annual precipitation (generally <350 mm/year). In such areas, groundwater must be used to meet all the needs of the population for water. As a consequence, careful management is required to ensure the sustainability of this scarce resource in response to the demands of urban centers, industry, agriculture, and tourism. The concept of the aquifer recharge rate is particularly useful in the quantification of these groundwater resources and can be used to form the basis of a decision support system. This study determined the potential recharge rate in the Haouz aquifer using a multi-criteria analysis that included both the major and minor factors influencing the rate of infiltration of water into the aquifer. The analysis was based on the use of a geographical information system supported by remote sensing techniques to develop thematic data layers. These layers were then used to describe the spatial variation of the factors influencing the recharge rate of the aquifer and were subsequently integrated and analyzed to derive the spatial distribution of the potential recharge. This approach was used to classify the Haouz Plain (Morocco) into three different zones with respect to the recharge rate, with recharge rates ranging from 3.5 to 18.2 %. 相似文献