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61.
Adel W. Felestteen Maher I. El-Soughier Mustafa S. Mohamed Mostafa N. S. Monged 《Arabian Journal of Geosciences》2014,7(9):3467-3480
A total of 51 samples, collected from the Jurassic sediments (Ras Qattara, Yakout, Khatatba, Masajid, and Alam El Bueib (member 6) formations) of Salam-3X well, were subjected to organic geochemical analysis. Of the samples, nine have been subjected to palynofacies investigation. Based on the sedimentary organic matter, these sediments show only one palynofacies type, indicating the presence of gas- and oil-prone source rocks and reflecting deposition under marginal dysoxic–anoxic to shelf-to-basin transition conditions. The total organic content of the samples analyzed is characterized by a wide range of content, including fair, good, very good, and excellent. The organic matter quality of these samples is concentrated around types III (gas prone), III–II (gas and oil prone), and II (oil prone), reflecting gas- and oil-prone sediments, with a tendency to generate gas rather than oil; the result matches with the palynological analysis data. The temperature of maximum pyrolytic hydrocarbon generation of analyzed samples are ranging between 440 and 457 °C, reflecting thermally mature organic matter. 相似文献
62.
Geological structures can be of great influence groundwater movement and accumulation in the surface and subsurface, and should therefore be taken into consideration in studies related to groundwater contamination impact. This study attempts to investigate the influence of geological structures on groundwater flow and groundwater salinity in Al Jaaw Plain, United Arab Emirates. A set of thematic maps derived from digital elevation model (DEM), LANDSAT, and Spaceborn Imagine Radar-C/X-Band Synthetic Aperture Radar were enhanced by applying Soble filter with 10 % threshold and equalization enhancement to reveal and map geological structures crosscut the entire region. Drainage pattern was derived from DEM automatically using D8 algorithm. The algorithm determines in which neighboring pixel any water in a central pixel will flow naturally. The trends of geological structures and drainage pattern extracted from remote sensing data were correlated with the spatial variation of hydraulic head, thickness aquifer, and groundwater salinity in the region. The results of the study reveal that the wadi courses, thickness of the aquifer, and topography are structural controlled by NNW–SSE, NE–SW, and ENE–WSW trending fault zones, significantly influencing the groundwater flow and groundwater contamination in Al Jaaw Plain. 相似文献
63.
This study focuses on the development of a farm of tidal turbines in the Khuran Channel. The important factors include the location of turbines and their hydrodynamic effects on the environment. A three-dimensional circulation model for the Persian Gulf is employed for the comprehensive evaluation of the tidal energy potential throughout the study area. The model is validated by using in situ observations of water level and current data.The appropriate potential points for extracting the tidal e... 相似文献
64.
In this paper we consider the translational–rotational motion of a spheroid satellite in the gravitational field, taking into account the asphericity of the earth. The harmonic coefficients of the earth’s gravitational field are taken up to J 4. The equations of motion are obtained in terms of the canonical elements of Delaunay-Andoyer. A first order solution is obtained using the perturbing technique of Lie series. 相似文献
65.
AbstractThe honey-bees mating programming (HBMP) algorithm is introduced as a novel tool for predicting suspended sediment concentration for the Mad River catchment near Arcata, USA. The paper also applies gene expression programming (GEP) as a comparison and shows that these two approaches can the produce transparent, nonlinear relationships between the independent and dependent variables. Some modifications have been made to the HBMP algorithm to improve its capability and efficiency. The results achieved from this method and GEP are compared with two different sediment rating curves based on regression techniques. The findings show that the results from both the HBMP and GEP methods are promising and outperform the results obtained from the sediment rating curves.
Editor D. Koutsoyiannis; Associate editor L. See 相似文献
66.
ABSTRACTClimate change/variability accompanied by anthropogenic activities can alter the runoff response of landscapes. In this study we investigate the integrated impacts of precipitation change/variability and landscape changes, specifically wetland drainage practices, on streamflow regimes in wetland-dominated landscapes in the Assiniboine and Saskatchewan River basins of the North American Prairies. Precipitation and streamflow metrics were examined for gradual (trend type) and abrupt (shift type) changes using the modified Mann-Kendall trend test and a Bayesian change point detection methodology. Results of statistical analyses indicate that precipitation metrics did not experience statistically significant increasing or decreasing changes and there was no statistical evidence of streamflow regime change over the study area except for one of the smaller watersheds. The absence of widespread streamflow and precipitation changes suggests that wetland drainage did not lead to detectable changes in streamflow metrics over most of the Canadian portion of the Prairies between 1967 and 2007.
Editor Z.W. Kundzewicz Associate editor None assigned 相似文献
67.
Due to the unique chemical properties and therefore wide range of applications, significant amounts of reactive dyes often end up in waste waters and this issue raises the need for more efficient treatment technologies. This work investigates the ability of magnetite nanoparticles functionalized with imidazolium based ionic liquid (IL) as an efficient sorbent for the removal of the Reactive black 5 from wastewater. Fourier transform infrared spectroscopy, X‐ray diffraction, transmission electron microscopy, thermo‐gravimetric analysis, and zeta potential measurement were used to characterize the synthesized nanosorbent. The results showed that under optimal conditions, the dye removal efficiency of the grafted IL is 98.5% after a single run. Regeneration of the used sorbent could be possible and the modified magnetic nanoparticles exhibited good reusability. The isothermal data of RB5 sorption conformed well to the Langmuir model and the maximum sorption capacity of IL@Fe3O4 for RB5 was 161.29 mg g?1. Thermodynamic study indicated that the adsorption is endothermic and spontaneous. The use of such a system can provide fast and efficient removal of the reactive dyes from wastewater by using an external magnetic field. 相似文献
68.
Identifying geological hazards related to tunneling in carbonate karstic rocks - Zagros, Iran 总被引:1,自引:0,他引:1
The construction of tunnels in carbonate karstic rocks has always been the most hazardous and problematic task in civil and mining engineering, as it can threaten tunneling project from safety, time and economic aspects. Therefore, it is essential to identify hazards resulting from construction in early stages of a project. The present paper is aimed to identify main geological hazards related to tunneling in carbonate karstic rocks in the Zagros Mountains. The process of identification relies upon a review of construction experiences obtained from several projects with a focus on the Kuhrang Tunnels. Obviously, groundwater inrush and tunnel flooding, ground inflow and fill-back of the tunnel, instability of weak fill materials, and TBM jamming are the main potential hazards of tunneling in the Zagros Mountains, imposing huge problems during construction. Inadequate understanding of hazards and not being prepared enough to take appropriate countermeasures are the main sources of the problems. In addition, the investigation of the present study provides guidelines to reduce the risks of tunneling in the carbonate karstic rocks with similar geological condition. 相似文献
69.
Despite its importance within environmental management strategies, little concern is shown to sulfide oxidation and/or hardpan
formation at neutral pH where dry condition prevails. Two gold mine tailings in Egypt, El Sid and Barramiya, were studied
for their geochemical/mineralogical properties, and climate influence on hardpan formation. The tailings are characterised
by homogeneous silt-sized sediments (>42%), have high carbonate, predominantly as calcite for El Sid and dolomite-ankerite
for Barramiya, and low-sulfide contents, chiefly as pyrite, galena and sphalerite for El Sid, and arsenopyrite–pyrite for
Barramiya. El Sid is characterised by high average concentrations of Pb (2,758 mg/Kg) and Zn (2,314 mg/Kg), its lower part
dominated by mafics, overlaid by granitoids. Barramiya has higher As (average 2,836 mg/Kg) content and represents a mixture
of mica-schists/mafics-ultramafics. During field investigations, no hardpans were identified, only bassanite and gypsum were
found at the surface of El Sid tailings, forming thin layers and desiccation crack fillings. Column experiments showed a thin
crust consisting of gypsum, halite and sodium sulfate formed at the top of the column of El Sid tailings after 2 weeks, this
was not recognized in the column from Barramiya. The homogenous thickened tailings deposition in both areas did not favour
hardpan formation, since the critical amounts of reacting sulfides were never achieved in individual lamina, due to missing
mineral/grain size fractionation. The high-temperature/low-water availability, characteristic for desert climate regions did
not allow significant sulfides oxidation. Therefore, both tailings will suffer from continuous erosion and spreading out of
contaminants to the environment for a prolonged period of time by sporadic flash floods. 相似文献
70.