The Beni Haoua,Algeria, Mw 4.9 earthquake: source parameters,engineering, and seismotectonic implications     

Khadidja Abbes  Louis Dorbath  Catherine Dorbath  Mohamed Djeddi  Farida Ousadou  Said Maouche  Nassima Benkaci  Abdennasser Slimani  Said Larbes  Djillali Bouziane 《Journal of Seismology》2016,20(2):655-667

A moderate Mw 4.9 earthquake struck the Beni Haoua (Algeria) coastal area on April 25, 2012. The mainshock was largely recorded by the accelerograph network of the Centre National de Recherche Appliquée en Génie Parasismique (CGS). The same day the earthquake occurred, eight mobile short period stations were deployed through the epicentral area. In this study, we use accelerogram and seismogram data recorded by these two networks. We combined the focal mechanism built from the first motion of P waves and from waveform inversion, and the distribution of aftershocks to well constrain the source parameters. The mainshock is located with a shallow focal depth, ～9 km, and the focal mechanism shows a nearly pure left lateral strike slip motion, with total seismic moment of 2.8?×?10¹⁶ N.m (M_w?=?4.9). The aftershocks mainly cluster on a narrow NS strip, starting at the coast up to 3–4 km inland. This cluster, almost vertical, is concentrated between 6 and 10 km depth. The second part of this work concerns the damage distribution and estimated intensity in the epicentral area. The damage distribution is discussed in connection with the observed maximum strong motion. The acceleration response spectrum with 5 % damping of the mainshock and aftershocks give the maximum amplitude in high frequency which directly affects the performance of the high-frequency structures. Finally, we tie this earthquake with the seismotectonic of the region, leading to conclude that it occurred on a N–S transform zone between two major compressional fault zones oriented NE–SW.  相似文献   

Potential Risk Assessment of Metal Consumption in Food Crops Irrigated with Wastewater          下载免费PDF全文

Muhammad U. Khan  Said Muhammad  Riffat N. Malik 《洁净——土壤、空气、水》2014,42(10):1415-1422

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Effect of Stress-Strain Conditions on Physical Precursors and Failure Stages Development in Rock Samples     

Kamel Baddari  Anatoly D. Frolov  Victor Tourtchine  Fayçal Rahmoune  Said Makdeche 《Acta Geophysica》2015,63(1):62-102

Precursory stages of failure development in large rock samples were studied and simultaneous observations of the space-time variation of several physical fields were carried out under different stress-strain states. The failure process was studied in detail. A hierarchical structure of discreet rock medium was obtained after loading. It was found that the moisture reduced the rock strength, increased the microcrack distribution and influenced the shape of the failure physical precursors. The rise in temperature up to 400 °C affected the physical precursors at the intermediate and final stages of the failure. Significant variations were detected in the acoustic and electromagnetic emissions. The coalescence criterion was slightly depending on the rock moisture and temperature effect. The possibility of identifying the precursory stage of failure at different strain conditions by means of a complex parameter derived from the convolution of physical recorded data is shown. The obtained results point out the efficiency of the laboratory modelling of seismic processes.  相似文献   

Effect of olive oil cake on water holding capacity of sandy soils in Libya     

R. M. El-Asswad  A. O. Said  M. T. Mornag 《Journal of Arid Environments》1993,24(4)

The effect of adding olive oil cake to two sandy soils on their abilities to retain water was investigated under controlled conditions. Olive oil cake was applied to the soils in pots and rates equivalent to 0, 5, 10, and 20% by weigh of the air-dried soil. Pots were incubated for 3 weeks at controlled conditions.The results show that the addition of oil cake significantly increased (P 0·05) the ability of the two sandy soils studied to retain water under all applied tensions. However, treatments with highest percentage of oil cake applied, had significantly higher water retention compared to those which had less. In terms of available water, which was calculated as the difference in volumetric water content between field capacity (-33 KPa) and wilting point (1·5 MPa), the highest olive oil cake applied doubled this difference in comparison to the control. An effect of soil texture was also noted. Generally, the influence of olive oil cake on the available moisture percentage was more pronounced in sand than the sandy loam.  相似文献   

Housing demolition and refugee resettlement schemes in the Gaza Strip     

Ahmed Said Dahlan Dr. 《GeoJournal》1990,21(4):385-395

This case study examines Israeli resettlement policy and housing demolition measures practiced in the Gaza Strip. Since the Gaza Strip is distinguished by a huge concentration of dispossessed Palestinian refugees maintained in large camps, the Israeli authorities, from the early stage of the 1967 occupation of the area, have devoted major effort to breaking up the camps and relocating their inhabitants elsewhere. The Israeli authorities have applied a clear policy of systematic destruction of refugee shelters and initiation of resettlement schemes, aimed in the short run at making the refugee camps less congested, while in the long run, the policy appears designed to remove these camps from the landscape entirely, since they remain a constant reminder of Palestinian uprootedness and exile. To date, the Israeli strategy of demolishing the entire refugee camp network has failed to achieve its final objective.  相似文献   

Groundwater pollution risk mapping for the Eocene aquifer of the Oum Er-Rabia basin, Morocco   总被引：2，自引：0，他引：2  

Said Ettazarini 《Environmental Geology》2006,51(3):341-347

Sustainable development requires the management and preservation of water resources indispensable for all human activities. When groundwater constitutes the main water resource, vulnerability maps therefore are an important tool for identifying zones of high pollution risk and taking preventive measures in potential pollution sites. The vulnerability assessment for the Eocene aquifer in the Moroccan basin of Oum Er-Rabia is based on the DRASTIC method that uses seven parameters summarizing climatic, geological, and hydrogeological conditions controlling the seepage of pollutant substances to groundwater. Vulnerability maps were produced by using GIS techniques and applying the “generic” and “agricultural” models according to the DRASTIC charter. Resulting maps revealed that the aquifer is highly vulnerable in the western part of the basin and areas being under high contamination risk are more extensive when the “agricultural” model was applied.  相似文献   

Correction to: Assessment of the Aeolian sand dynamics in the region of Ain-Sefra (Western Algeria), using wind data and satellite imagery     

Said Bouarfa  Sid Ahmed Bellal  Mohammed Nadir Belmahi 《Arabian Journal of Geosciences》2018,11(10):240

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Assessment of the Aeolian sand dynamics in the region of Ain Sefra (Western Algeria), using wind data and satellite imagery     

Said Bouarfa  Sid Ahmed Bellal 《Arabian Journal of Geosciences》2018,11(3):56

The region of Ain Sefra is an arid region suffering from sand encroachment. In this study, we are calculating the shifted sand quantity and efficient wind directions during a period of 30 years (1985 to 2015) in order to classify the danger. The study shows that efficient winds in the region are characterized by their potential drift estimated at 220 till 329. This classifies the region as medium. Besides, the resultant drift potential is 76 to 99 with a migration coefficient of 0.3 which gives a medium classification to the zone and proves the Aeolian erosion complex system and its interrelation with other factors. Efficient winds generally blow from South-west to North-east with an angle of 234°. Furthermore, there are other directions causing sand drifting. Sand movement quantity is estimated between 23.03 and 15,224 m³/m/year according to effective wind threshold speed, which is 5 to 6 m/s. Autumn is the period when sand mobility is higher, but it decreases in winter. On the other hand, sand potential movement was well shown through satellite imagery between 1985 and 2015. Indeed, it closely corresponded to the previous study. It showed sand movement direction from South-west to North-east, and sand surface increase reached 16.44% of the global zone surface. Whereas, it decreased ??2.5% between 1985 and 2015. There is an important concentration of sand accumulation under the western mountain foothills along which sand moves. This shows that the ground particularities play a crucial role in this phenomenon.  相似文献   

The nexus between income inequality,economic growth and environmental degradation in Pakistan     

Amdadullah Baloch  Said Zamin Shah  Zaleha Mohd Noor  Hussian Bakhsh Magsi 《GeoJournal》2018,83(2):207-222

This study examines the impact of income inequality and economic growth on environmental degradation in Pakistan using ARDL bounds testing approach for the period 1966–2011. Empirical results for the aggregate CO₂ emissions and its four sources such as CO₂ emissions from solid fuel, liquid fuel and gaseous fuel consumption as well as electricity and heat production confirm the existence of long run co-integrated relationship between income inequality, economic growth and environment degradation. The estimated results indicate that carbon emissions increase as the income gap expands in Pakistan. Besides the negative impact of industrial share and population density on CO₂ emissions, we also confirm that economic growth in Pakistan comes up with higher emissions. Hence, the hypothesis of EKC is not valid for Pakistan during the study period. Our empirical findings are robust as evidenced by dynamic ordinary least squared and the U-tests. Overall, this study suggests that the distribution of income matters to aggregate carbon emissions and focus should be made on sustained economic growth to reduce pollutants and hence CO₂ emission in the study area.  相似文献   

Incidences of water-rock interaction on natural resources characters,Oum Er-Rabia Basin (Morocco)   总被引：1，自引：1，他引：0  

Said?EttazariniEmail author 《Environmental Geology》2004,47(1):69-75

The Oum Er-Rabia Basin provides important water resources from a multi-layer aquifer system of which the Turonian limestone aquifer constitutes the main potential resource. The same basin is also known by its wealth in phosphates and comprises the Ouled Abdoun Series, the largest Moroccan phosphate occurrence. The present work attempts to characterize the interaction of natural resources with their impacts on water and phosphates quality. Hydrogeochemical data on waters of the Turonian and the Eocene aquifers, as well as their petrographical analyses, by optical and electronic microscopes and by the X-ray diffraction method on weathered and non-weathered rocks of relative aquifers, have shown that water-rock interaction has a large influence on the quality of water and phosphate resources in the Oum Er-Rabia Basin.  相似文献