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31.
Abdelkader Benaïssa Zahia Benaïssa Tahar Aïfa Amar Boudella 《Swiss Journal of Geoscience》2009,102(2):297-306
To improve the signal to noise ratio of the vertical seismic profile recordings, we used a filtering method based on pattern
recognition. It consists in recognizing along the seismic trace, corresponding to the arrivals of various events, the shape
of the P wavelet considered as the training signal. This recognition is made of projections which retain only the signals
similar in shape to the P wavelet, the others being attenuated according to their degree of resemblance to the training wavelet.
The study undertaken on synthetic and real data shows that this method acts as an effective filter. However, it still depends
on a training signal that must be well defined and identifiable. 相似文献
32.
Assessment of water quality index for the groundwater in the upper Cheliff plain,Algeria 总被引:1,自引:0,他引:1
Abdelkader Bouderbala 《Journal of the Geological Society of India》2017,90(3):347-356
Assessment of groundwater suitability for drinking and agricultural purposes was carried out in the plain of upper Cheliff. The study area covers an area of 375 km2 and lies in a semiarid climate. Groundwater is the major source for domestic and agricultural activity in this area. Groundwater samples were collected from 19 wells during dry and wet periods in 2012, and they were analyzed for major cations and anions and compared with drinking and irrigation specification standards. The concentration of the majority of chemical constituents exceeds the standards of WHO as a result of various sources of pollution. It indicates the dominance of groundwater types: Ca-Mg-Cl, and Ca-Mg-HCO3. Suitability of groundwater for drinking was evaluated based on the water quality index; it shows more than 60% of samples have very poor quality for dry and wet periods, which means water is severely contaminated and unsuitable for drinking purpose. In terms of the irrigation usage, generally groundwater is suitable for both periods in the major part of the plain. The Mineralization processes in this area is determined by the lithology of the aquifer (exchange water-rock), by anthropogenic factors (discharges of urban sewage, use of fertilizers) and also by evaporation (semi-arid climate). 相似文献
33.
Gärtner Andreas Youbi Nasrrddine Villeneuve Michel Sagawe Anja Hofmann Mandy Mahmoudi Abdelkader Boumehdi Moulay Ahmed Linnemann Ulf 《International Journal of Earth Sciences》2017,106(8):2747-2769
International Journal of Earth Sciences - Detrital zircon provenance studies are an established tool to develop palaeogeographic models, mostly based on zircon of siliciclastic rocks and isotope... 相似文献
34.
Mortadha Ben Hassine Olfa Boussadia Ahmed Ben Abdelkader Ines Moula Mariem El Hafi Mohamed Braham 《Arabian Journal of Geosciences》2017,10(14):302
Olive trees are grown under high evaporative demand and less precipitations that are variable in time and space especially in semi-arid conditions. The objective of this work is to determine the most efficient water treatment applied in an olive field (Olea europaea L. cv Chemlali) from the 98th to the 294th Julian day, in Tunisian semi-arid conditions. The choice of this time frame was done to control the effect of irrigation on the trees behavior in the irrigation period of the year (from April to October) and determine the most sensitive phenological stages to irrigation. For this reasons, two water treatments were applied: T100% (irrigation at 100% of Available Water Content (AWC)) and T50% (irrigation at 50% AWC). The results show that, according to leaf water potential, carbon isotope discrimination, and olive production parameters, the T50% AWC water treatment is the most efficient. The leaf water potential of the two water treatments applied has not exceeded ?2.5 MPa during the whole experiment which indicates that the trees of the two water treatments were not stressed. The T50% AWC shows a water use efficiency of 5.18 g/l compared to 2.93 g/l for T100% water treatment. This result demonstrate that Chemlali cultivar valorizes better low quantities of water rather than high quantities, so saving 50% of water resources applied will ensure the sustainability of water resources and stability of olive production. 相似文献
35.
Clay and Marl Formation Susceptibility in Mila Province,Algeria 总被引:2,自引:2,他引:0
Djamel Athmania Abdelkader Benaissa Achour Hammadi Mounir Bouassida 《Geotechnical and Geological Engineering》2010,28(6):805-813
In Mila Province, Algeria (a.k.a Mila Wilaya), sensitive clays presenting shrinkage-swelling phenomena are widespread, covering
large areas. Due to this, constructions and infrastructures sustainability built on such soils is questionable. Such clays
sensitivity is amplified by seasonal rainfall deficits which reaches extreme magnitudes. In order to develop disasters’ prevention
measures, we present in this work, areas mapping susceptible to shrinkage-swelling phenomenon by adopting a French method
developed by B R G M. This method takes into account three measurable characteristics: i.e. lithological, mineralogical and
geotechnical, of clayey formations identified in the studied sector. Based on these characteristics, three scores are attributed
for each formation. Then, the susceptibility index is the obtained score average for each clayey formation. The susceptibility
map is established on this index basis with three classes: low, medium, high. 相似文献
36.
Evaluation and numerical modeling of seawater intrusion in the Gaza aquifer (Palestine) 总被引:3,自引:1,他引:3
A numerical assessment of seawater intrusion in Gaza, Palestine, has been achieved applying a 3-D variable density groundwater flow model. A two-stage finite difference simulation algorithm was used in steady state and transient models. SEAWAT computer code was used for simulating the spatial and temporal evolution of hydraulic heads and solute concentrations of groundwater. A regular finite difference grid with a 400 m2 cell in the horizontal plane, in addition to a 12-layer model were chosen. The model has been calibrated under steady state and transient conditions. Simulation results indicate that the proposed schemes successfully simulate the intrusion mechanism. Two pumpage schemes were designed to use the calibrated model for prediction of future changes in water levels and solute concentrations in the groundwater for a planning period of 17 years. The results show that seawater intrusion would worsen in the aquifer if the current rates of groundwater pumpage continue. The alternative, to eliminate pumpage in the intruded area, to moderate pumpage rates from water supply wells far from the seashore and to increase the aquifer replenishment by encouraging the implementation of suitable solutions like artificial recharge, may limit significantly seawater intrusion and reduce the current rate of decline of the water levels. 相似文献
37.
Ridha Abdessalem Gharbi Lassaâd Chihi Mongi Hammami Abdelkader Soumaya Ali Kadri 《Comptes Rendus Geoscience》2005,337(14):1293-1300
The geodynamic evolution of the diapir of Zag Et Tir is the result of the coexistence of the diapiric and tectonic activity from the Upper Cretaceous until the Quaternary. The interference of the tectonic and diapiric phenomena is at the origin of the basin individualization with differential sedimentation during the Miocene. This explains the current distribution of the Neogene deposits on both sides of Zag Et Tir Triassic structure. The submeridian faults that subdivide our sector played a significant role during the Atlasic compression, inducing an unequal distribution of the folds on both sides of these accidents, as well in kind as in number, showing the anteriority of the faults compared to the folds. To cite this article: R.A. Gharbi et al., C. R. Geoscience 337 (2005). 相似文献
38.
Abdennour Mohamed Amine Douaoui Abdelkader Barrena Jesús Pulido Manuel Bradaï Abdelhamid Bennacer Amel Piccini Chiara Alfonso-Torreño Alberto 《中国地球化学学报》2021,40(2):234-250
Acta Geochimica - The agriculture in Biskra, southeastern Algeria, is based on traditional practices and characterized by small irrigated fields. In the last decades, the increasing demand in water... 相似文献
39.
Changes of snow cover in Poland 总被引:2,自引:2,他引:0
Małgorzata Szwed Iwona Pińskwar Zbigniew W. Kundzewicz Dariusz Graczyk Abdelkader Mezghani 《Acta Geophysica》2017,65(1):65-76
The present paper examines variability of characteristics of snow cover (snow cover depth, number of days with snow cover and dates of beginning and end of snow cover) in Poland. The study makes use of a set of 43 long time series of observation records from the stations in Poland, from 1952 to 2013. To describe temporal changes in snow cover characteristics, the intervals of 1952–1990 and of 1991–2013 are compared and trends in analysed data are sought (e.g., using the Mann–Kendall test). Observed behaviour of time series of snow-related variables is complex and not easy to interpret, for instance because of the location of the research area in the zone of transitional moderate climate, where strong variability of climate events is one of the main attributes. A statistical link between the North Atlantic Oscillation (NAO) index and the snow cover depth, as well as the number of snow cover days is found. 相似文献
40.
What can we learn from the projections of changes of flow patterns? Results from Polish case studies 总被引:1,自引:1,他引:0
Mikołaj Piniewski Hadush Kidane Meresa Renata Romanowicz Marzena Osuch Mateusz Szcześniak Ignacy Kardel Tomasz Okruszko Abdelkader Mezghani Zbigniew W. Kundzewicz 《Acta Geophysica》2017,65(4):809-827
River flow projections for two future time horizons and RCP 8.5 scenario, generated by two projects (CHASE-PL and CHIHE) in the Polish-Norwegian Research Programme, were compared. The projects employed different hydrological models over different spatial domains. The semi-distributed, process-based, SWAT model was used in the CHASE-PL project for the entire Vistula and Odra basins area, whilst the lumped, conceptual, HBV model was used in the CHIHE project for eight Polish catchments, for which the comparison study was made. Climate projections in both studies originated from the common EURO-CORDEX dataset, but they were different, e.g. due to different bias correction approaches. Increases in mean annual and seasonal flows were projected in both studies, yet the magnitudes of changes were largely different, in particular for the lowland catchments in the far future. The HBV-based increases were significantly higher in the latter case than the SWAT-based increases in all seasons except winter. Uncertainty in projections is high and creates a problem for practitioners. 相似文献