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Sixty-five sediment samples and 25 water samples were collected from Al-Mujib reservoir, central Jordan, in order to investigate the heavy metal and ionic contamination assessment. Therefore, to achieve this aim, water and sediment samples were collected during winter and summer seasons (2007) from Al-Mujib reservoir and the areas surrounding it. The study shows that there are elevated levels of SO4 2−, Cl and Na+ in reservoir water, which might originate from anthropogenic activities in the reservoir catchment area. In addition, the reservoir water has higher total hardness (TH) values together with high Ca and Mg contents. This might be attributed to pH of reservoir water and the nature of the rocks exposed in the catchment area. The average levels of heavy metals in reservoir sediments are Fe = 14,888.1, Cu = 17.8, Zn = 88.6, Ni = 38.7, Cd = 4.4, Mn = 337.9 and Pb = 6.1 mg/kg, which are lower than that observed in Wadi Al-Arab reservoir, northern Jordan. The values of enrichment factor are Cd = 35.5, Ni = 3.02, Zn = 2.54, Cu = 1.26, Mn = 1.2 and Pb = 0.57; these values indicate that heavy metals in sediments of Al-Mujeb reservoir have a different anthropogenic incrimination inputs. The study showed that the sediments are polluted with Cd, relatively contaminated with Ni and Zn and uncontaminated with respect to Mn, Pb and Cu.  相似文献   
2.
Eight selected heavy metals and phosphorus (Fe, Zn, Pb, Cu, Cr, Cd, Ni and P) were analyzed in the dust fall samples collected from the surrounding areas adjacent to Al-Hisa phosphate mine central Jordan during summer 2008. The chemical analysis was done using the ICP-AES, after being digested with (HNO3/HCl/HF) acid mixture, beside the identification of their mineral constituents using the XRD. Moreover, the particulate matter (PM) size was investigated and divided into four fractions (PM2.5, PM2.5–10, PMC10–100 and PM>100). The PM10–PM100 were found to be the most abundant in the local atmosphere followed by PM2.5–PM10, while the respirable fraction (PM2.5) and giant fraction (PM>100) showed lower levels. The studied samples contain less PM2.5 and PM10 particulates (9.39 and 28.67), respectively, than samples located far from the mine area (blank samples) (17.32 and 51.7) for PM2.5 and PM10, respectively. The meteorological effects, mainly the prevailing wind direction beside the distance to emission sources affect the distribution of dust particle sizes. Heavy metal contents in studied samples are similar to some extent to those found in Isa Town (Bahraian), which related to similar arid and low precipitation climatic conditions. The effect of phosphate mining activities was obvious as indicated from the presence of apatite as the main mineral phase and the higher P contents. Moreover, the studied samples contain higher Zn, Ni, Cu and to lesser extent Cr than blank samples. They exhibited a significant positive correlation with P, as they are usually associated with the phosphate rocks.  相似文献   
3.
The present work deals with the geologic setting and mineralogical and geochemical study of Late Precambrian magmatic rocks especially the felsic dike swarms of northeast Aqaba complex in South Jordan. The northeast Aqaba complex represents one of the most significant regions in the South Jordan basement. The basement rocks in the studied region are composed of schists, gneisses, migmatites, met gabbros, diorite, and granite. It is invaded by post-orogenic dike swarms. The post-orogenic dike swarms have been recognized as felsic dikes of dacite, rhyodacite, and rhyolite composition. They are composed of plagioclase, K-feldspar, quartz, biotite, and hornblenble with a porphyritic texture. Chemically, they are enriched in compatible elements especially in the large ion lithophile elements such as K, Rb, and Ba. The values of A/NK are more than A/CNK, indicating that dacitic dike swarms have metaluminous nature. Meanwhile, the values of A/NK are less than A/CNK in rhyodacitic and rhyolitic dike swarms of prealuminous nature. This felsic dike can be related to an intercontinental setting that was accompanied by a chemical evolution of the extensional movements and is formed by partial melting of crustal rocks, which are already known from other areas in the northeast portion of the Arabian-Nubian Shield.  相似文献   
4.
The bed and suspended (slime) sediment phases associated with effluent water that are produced from phosphate-ore-upgrading process at Al-Abyad mine in the southern part of Jordan were analyzed chemically and mineralogically. The results show that the effluent water is highly oxic and mildly alkaline in nature. The geochemical behavior of each phase was controlled by the effluent water physicochemical parameters, sediment particle size, mineralogical constituents of the studied phases, and the prevailing climatic nature of the area. Bed sediments have higher concentrations of many elements than slime. Accordingly, the bed sediments can be considered as a sink rather than a pool for many elements. The geochemical dissociation of major oxides and trace elements between bed and slime sediments was evident using t test, particularly between P2O5, SiO2, CaO, K2O, Mn, Sr, Y, and Co, and to lesser extent, V, U, Zn, and Cr. This might be attributed to effluent water characteristics, mineralogy, and the presence of fine-grained materials. The spatial distribution of major oxide and trace element concentrations along the stream drainage exhibited a slight increase with distance either in bed or slime sediment phases. However, they increased suddenly at the last three sampling sites, which might be due to the abundance of fine-grained materials that are mainly composed of clay minerals (montmorillonite) that would enhance the adsorption process. Moreover, the XRD results confirmed the existence of elemental geochemical dissociation as a function of mineral control.  相似文献   
5.
Calcareous vertisol soil is the dominant agricultural soil type and covers over 80% of the agricultural cultivated land in Jordan. This type of soil is characterized by its high pH and CaCO3 content, which made the heavy metals including Zn to be oxidized and adsorbed onto soil. Therefore, this type of soil is regarded as potentially Zn deficient. The effect of Zn initial concentration and average rainfall on the Zn adsorption and desorption from three types of calcareous vertisol soils has been examined. The amount of Zn adsorbed and desorbed at equilibrium increased with increasing Zn initial concentration for each of the three investigated soils. However, the percentage of adsorption and desorption decreased as the initial concentration of Zn ions increased. Moreover, results showed that rainfall has no influence on the behavior of Zn in the calcareous vertisol soils. Freundlich and Redlich-Peterson models provide the best representation of the experimental data, followed by the Langmuir model.  相似文献   
6.
A total of 115 urban soil samples collected on grid bases from Al-Karak, South Jordan, were investigated for their field and dual-frequency magnetic susceptibility (χ field, χ d) and heavy metal content using Bartington susceptibility meters and ICP-MS. The upper soils have higher magnetic susceptibility values than lower soils, and large particles contain more heavy metals and higher magnetic susceptibility than smaller particles. This might be attributed to the lack of pedogenesis due to arid climate influence. Within the upper soil all heavy metal showed positive significant correlation with upper soil low-frequency χ dlf. This was evident from the distribution maps produced by Surfer 9.0 for χ dlf and heavy metals. The results showed that higher χ dlf is associated with traffic-dominated sites more than other areas. The frequency-dependent susceptibility (χfd %) falls between 2 and 10 %, which indicate the presence of admixture of fine supermagnetic particles. Mildly correlation exists between χfd % and χ dlf, which implies that soils contain anthropogenic multi-domain grains. Selected samples have been analyzed for their mineral constituents; the results indicate the presence of magnetite as the main magnetic mineral. This confirms the anthropogenic source of pollution mainly from the vehicle-related materials. The results indicate the applicability of magnetic susceptibility for pollution detection.  相似文献   
7.
A method for analyzing the earthquake response of elastic, cylindrical liquid storage tanks under vertical excitations is presented. The method is based on superposition of the free axisymmetrical vibrational modes obtained numerically by the finite element method. The validity of these modes has been checked analytically and the formulation of the load vector has been confirmed by a static analysis. Two forms of ground excitations have been used: step functions and recorded seismic components. The radial and axial displacements are computed and the corresponding stresses are presented. Both fixed and partly fixed tanks are considered to evaluate the effect of base fixation on tank behaviour. Finally, tank response under the simultaneous action of both vertical and lateral excitations is calculated to evaluate the relative importance of the vertical component of ground acceleration on the overall seismic behaviour of liquid storage tanks.  相似文献   
8.
The Dead Sea as a unique geological and geographical phenomenon has an effect on its adjacent areas. Therefore, 17 sampling sites at the eastern highlands facing the Dead Sea; beside three blank sites were collectedlocated during summer (2005). The aim was to investigate such influence on the chemical and mineralogical composition of dry deposition, and to measure the settling rate. The investigations showed that the depositional rate at the studied sites was much lower than other areas at central and southern Jordan. The average heavy metal contents are almost similar in all sampling sites and the blanks, and they exhibit similar enrichment series, whereas, the meaningful difference between sampling sites and blank was in cation and anion content, which caused different enrichment series between the two sites. The index of pollution (IP) confirms that mainly cations and anions have IP > 1.0 and they dominate the southern and the closest sampling sites to the Dead Sea. The XRD results reveals that the studied samples have minor phases such as halite, gypsum, and dolomite. Meanwhile, these mineral phases are not found in blank samples. All these results indicates the influence of the Dead Sea, as it is a highly saline large water mass, which accompanied with by high evaporation rates causing causes the atmosphere over the Sea to be enriched with these cations, anions, elements and minerals, which eventually are adsorbed in air particulate or carried out as dry deposition and transported by the NW–SE prevailing winds, and fall over the eastern highlands.  相似文献   
9.
This work is a complementary investigation to the earlier urban soil survey for a rapidly growing city of relatively high traffic density. Therefore, it aims to apply the environmental magnetism approach to assess the roadside pollution at a known polluted site. The used magnetic proxies are the initial magnetic susceptibility and saturation magnetization. The results prove the applicability of this method in detecting roadside pollution. The shape and magnitude of the magnetic signals was affected by the topography and prevailing wind direction that caused the magnetic peaks to be shifted accordingly. Particle size was found to affect the magnetic material content, where sand size (63–150 μm) bears the highest magnetic signals relative to smaller silt size (<63 μm). The magnetic anomalies coincided positively with heavy metal pollution in the studied site, which might indicate that the magnetic materials serve as an effective proxy for the metallic pollution (i.e., Fe, Ni, Pb, Cu, and Zn) originated mainly from vehicular sources.  相似文献   
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