Optimization of cumulative trapped sediment curve for an arid zone reservoir: Foum El Kherza (Biskra,Algeria)     

F.Z. Tebbi  H. Dridi  G.L. Morris 《水文科学杂志》2013,58(7):1368-1377

Abstract

Reservoir silting is one of the principal problems affecting the performance of dams in Algeria from the standpoint of reservoir capacity for storage. Foum El Kherza Reservoir (also known as Foum El Gherza), near Biskra Town, Algeria, is subject to dredging operations with the intent of recovering 70% of its initial storage capacity of 47 hm³ (million cubic metres). The forecasting of sediment volume trapped in the reservoir is essential to plan the future use of this resource and to sustain irrigation for the palm groves characteristic of the region. However, there are currently no sediment data, nor a sediment rating curve, for predicting sediment inflow based on hydrological data. This paper describes the optimization of a cumulative trapped sediment curve for Foum El Kherza Reservoir based on 44 years of daily inflows, by using a spreadsheet optimization tool, Microsoft Excel® Solver to calibrate the cumulative sediment load against the cumulative sediment inflow as documented by eight bathymetric surveys since the dam construction.

Editor D. Koutsoyiannis; Associate editor A. Montanari

Citation Tebbi, F.Z., Dridi, H., and Morris, G.L., 2012. Optimization of cumulative trapped sediment curve for an arid zone reservoir: Foum El Kherza (Biskra, Algeria). Hydrological Sciences Journal, 57 (7), 1368–1377.  相似文献   

Reuse of waste water: impact on water supply planning / Remploi de l'eau résiduaire: influence sur la planification des systèmes de distribution des eaux     

GEORGE F. MANGAN Jr. 《水文科学杂志》2013,58(2):235-244

Abstract

As the urban population of the world increases and demand on easily developable water supplies are exceeded, cities have recourse to a range of management alternatives to balance municipal water supply and demand. These alternatives range from doing nothing to modifying either the supply or the demand variable in the supply-demand relationship. The reuse or recycling of urban waste water in many circumstances may be an economically attractive and effective management strategy for extending existing supplies of developed water, for providing additional water where no developable supplies exist and for meeting water quality effluent discharge standards. The relationship among municipal, industrial and agricultural water use and the treatment links which may be required to modify the quality of a municipal waste effluent for either recycling or reuse purposes is described. A procedure is described for analysing water reuse alternatives within a framework of regional water supply and waste water disposal planning and management.  相似文献   

阿尔及利亚Hoggar地盾金矿成矿特征——以Tin-Zakri金矿为例     

王猛  王敏  周明岭  汪昌亮 《地质与资源》2016,25(1):69-73

阿尔及利亚金矿主要分布于南部地区Hoggar地盾.受泛非运动影响,Hoggar地盾与西非克拉通挤压碰撞,区内金矿沿南北向断裂带分布.Tin-Zakri金矿位于Hoggar地盾近南北向Tiririnienne成矿带上,受区内北西向主构造控制.目前发现与矿化有关的矿化蚀变带30条,其中规模较大的有2条（27、30号脉）,矿体赋存在片理化岩带内,呈北西向或近南北向脉状展布,以石英脉的形式断续分布在韧性剪切带中.围岩蚀变特征明显,绢云母化为金矿的直接找矿标志,绿泥石化片理化带是金矿找矿的重要线索.  相似文献   

SEDIMENT RATING CURVES DEVELOPED ON STAGE AND SEASONAL MEANS IN DISCHARGE CLASSES FOR THE MELLAH WADI, ALGERIA     

KAMEL KHANCHOUL  MARGARETA B. JANSSON 《Geografiska Annaler: Series A, Physical Geography》2008,90(3):227-236

The focus of the present study was to estimate suspended sediment load from the Mellah catchment (550 km²) during storms. Suspended sediment rating curves were developed on data from a 23-year period. The regression technique of this paper involves a division of data into discharge-based classes, the mean concentrations and discharges of which are used to develop power regressions through log-transformation. Sediment rating curves were also developed on means of data grouped into seasons and stages. Sediment loads estimated by rating curves uncorrected for bias involved underestimations of down to 9% compared with loads from measured concentrations. Correction for bias reduced underestimations to a range from 0.79 to 3%. Rating curves divided into rising and falling stages had the lowest underestimation and were used to estimate load during periods without concentration measurements. During the 23-year study period, the mean annual suspended sediment yield was 373 TI km².
Sediment transport is dominated by winter storms accounting for 61% of the annual load. A high exponent 'b' of the power regression equations during the winter season confirms the intense geomorphic work by winter season storms caused by high intensity rainfall, low vegetation cover, and heavy machine activity in the fields.  相似文献   

Numerical simulation and land subsidence control for deep foundation pit dewatering of Longyang Road Station on Shanghai Metro Line 18     

LI Wen-yong  FU Li  ZHU Zheng-feng 《地下水科学与工程》2019,7(2):133-144

In terms of controlling groundwater in deep foundation pit projects, the usual methods include increasing the curtain depth, reducing the amount of pumped groundwater, and implementing integrated control, in order to reduce the drawdown and land subsidence outside pits. In dewatering design for confined water, factors including drawdown requirements, the thickness of aquifers, the depth of dewatering wells and the depth of cutoff curtains have to be considered comprehensively and numerical simulations are generally conducted for calculation and analysis. Longyang Road Station on Shanghai Metro Line 18 is taken as the case study subject in this paper, a groundwater seepage model is developed according to the on-site engineering geological conditions and hydrogeological conditions, the excavation depth of the foundation pit as well as the design depth of the enclosure, hydrogeological parameters are determined via the pumping test, and the foundation pit dewatering is simulated by means of the three-dimensional finite difference method, which produces numerical results that consistent with real monitoring data as to the groundwater table. Besides, the drawdown and the land subsidence both inside and outside the pit caused by foundation pit dewatering are calculated and analyzed for various curtain depths. This study reveals that the drawdown and the land subsidence change faster near the curtain with the increase in the curtain depth, and the gradient of drawdown and land subsidence changes dwindles beyond certain depths. In this project, the curtain depth of 47/49 m is adopted, and a drawdown-land subsidence verification test is completed given hanging curtains before the excavation. The result turns out that the real measurements basically match the calculation results from the numerical simulation, and by increasing the depth of curtains, the land subsidence resulting from dewatering is effectively controlled.  相似文献   

The Murdjadjo, Western Algeria, fault-related fold: Implications for seismic hazard     

Youcef Bouhadad 《Journal of Seismology》2001,5(4):541-558

The murdjadjo (Oran) geological structure which consists of an asymmetricfold has been studied. The anticline has a length of about 32 km and isN050 trending. Its relationship with the relatively high historical seismicityof the region is analysed. New critical investigations of contemporary documents enabled us to re-evaluate the December, 12, 1959(M_s = 4.7) and the May 12, 1889 (M_s = 4.6) earthquakes. Fieldobservations reveal the existence of a fault which affect the south-easternflank of the Murdjadjo anticline. The fault dips 60^° to the NW andcut the tilted Neogene deposits which juxtaposes the Quaternary tilteddeposits. A NE-SW-trending direction of stream pattern underlies thefaulted flank of the anticline. Furthermore, offset of stream patternindicate a strike lateral slip component of the fault. Marine terracesmapped along the Oran coast indicates a uniform uplift rate of0.18 mm/yr which may be compared to the coseismic rate obtained inthe chelif region. Also, development of secondary small plain on theuplifted flank, the high subsidence in the Mleta quaternary plain whichjuxtaposes the faulted flank constitute evidence of recent tectonicmovements. The Murdjadjo fault, composed by two segments, mayproduce in the future strong earthquakes of magnitude equal or greaterthan 6.5. This fact suggests that the Oran earthquake of October 9, 1790(M = 7.5) which produced sea waves along the Spanish coast is likelygenerated by the Murdjadjo fault- related fold. Recurrence of earthquakedetermined on the basis of historical seismicity suggests a return period ofabout 1000 years for an earthquake of M = 7.3 which seem underestimatedcompared to the paleoseismic data available in The Tell atlas of Algeria.  相似文献   

Seismotectonics and seismic quietness of the Oranie region (Western Algeria): The Mascara earthquake of August 18th 1994, Mw = 5.7, Ms = 6.0     

A. Ayadi  F. Ousadou-Ayadi  S. Bourouis  H. Benhallou 《Journal of Seismology》2002,6(1):13-23

The plate dynamics in the central western Mediterranean region is characterised by a collision between the Eurasian and African plates. In response to this dynamics, many systems of faults and folds having a NE-SW and E-W trending have been generated along the Tellian Atlas of Algeria. The Oranie region (north western Algeria) has experienced some significant earthquakes in the last centuries, the most important one is that of Oran city on February 9^th 1790, I_o = XI which destroyed the town completely and caused the loss of many lives. Since 1790 no other event was so disastrous except that of August 18^th 1994, M_w = 5.7, which struck Mascara province (Algeria) at 01 h 13 mn GMT. Since the beginning of this century the region has been dominated by a seismic quietness. Thus, no event with magnitude larger than 5.5 have occurred in this area. In relation with this recent event, a seismotectonic framework summarising the tectonic, seismicity and focal solution results is presented. The Maximum Observed Intensities Map (MOI) made for Algeria (Bezzeghoud et al., 1996) is also used to show that the Mascara region is located in an VIII-X intensity zone, which explain partially the casualties caused by the 18/08/1994 (M_w = 5.7) earthquake. This earthquake is not anomalous compared to historical records but is unusual compared to recorded seismicity of this century. The seismotectonic map made in this study and also the review of the focal solutions given by the EMSC, Harvard, and other authors shows that our event is probably associated with a source belonging to a system of faults located in the vicinity of the village of Hacine where the maximum damage was observed.  相似文献   

Circumgranular bassanite in a gypsum crust from eastern Algeria – a potential palaeosurface indicator     

Florias Mees  Georges Stoops 《Sedimentology》2003,50(6):1139-1145

Detrital sand grains are surrounded by thin bassanite coatings in the upper part of a coarse-crystalline gypsum crust from the Algerian Sahara. The bassanite developed by topotactic replacement of the surrounding gypsum in the absence of a liquid phase. Heating experiments using a gypsum crystal with sand inclusions produced similar patterns and textures. In one experiment, bassanite developed around quartz and carbonate grains but not along the sides of the heated gypsum crystal. This is the result of differences in heat capacity between gypsum, quartz and calcite. Bassanite formation in the crust from Algeria was not controlled by differences in thermal properties. Instead, the bassanite apparently formed under conditions of thermal equilibrium. The occurrence of bassanite as circumgranular coatings in the crust is interpreted as being related to the availability of submicroscopic space along the contact between the gypsum cement and the enclosed sand grains. The presence of coatings of this type, or derived relict features, is a potential criterion for the recognition of palaeosurfaces.  相似文献   

联合国召开阿尔及利亚地震救援经验总结会     

黄建发 《国际地震动态》2003,(12):17-21

为了总结在阿尔及利亚地震救援工作中存在的问题和经验教训，联合国人道主义事务办公室于2003年9月9～10日在瑞士日内瓦举行了“阿尔及利亚地震救援经验工作会议”。来自参加过地震救援的部分国家、阿尔及利亚和有关国际机构的代表共93人参加了会议。文章介绍了会议讨论的问题，包括灾害初期预警、动员和救援队的部署；现场协调；搜救工作和使用指南。最后，针对我国国际救援队的工作，提出具体建议。  相似文献   

Earthquake Hazard Assessment in the Oran Region (Northwest Algeria)   总被引：4，自引：1，他引：4  

Bouhadad  Youcef  Laouami  Nasser 《Natural Hazards》2002,26(3):227-243

This paper deals with the probabilistic seismic hazard analysis carried out in the Oran region, situated in the Northwest of Algeria. This part of Algeriawas historically struck by strong earthquakes. It was particularly affected during theOctober 9, 1790 Oran earthquake of intensity X. The main purpose of this work is to assessseismic hazard on rocks in order to provide engineers and planners with a basic tool for seismicrisk mitigation. The probabilistic approach is used in order to take into account uncertaintiesin seismic hazard assessment. Seismic sources are defined in the light of the most recentresults obtained from seismotectonics analyses carried out in North Algeria.Source parameters such as b-values, slip rate and maximum magnitude are assessed for eachseismic source. The attenuation of ground shaking motion with distance is estimated byusing attenuation relationships developed elsewhere throughout the world (Sadigh et al., 1993; Ambraseys and Bommer, 1991). The two relationships agree well with the local data. Differentchoices of source parameter values and attenuation relationships are assigned weights in alogic tree model. Results are presented as relationships between values of peak groundacceleration (PGA) and annual frequency of exceedance, and maps of hazard for returnperiods of 200 years and 500 years. A maximum peak ground acceleration of 0.42 g is obtainedfor the Oran site for a return period of 500 years.  相似文献