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41.
An integrated petrophysical well log and core data analysis of the Alam El Bueib-3D (AEB-3D) and Alam El Bueib-3E (AEB-3E) reservoirs, Tut oil field, North Western Desert, Egypt, allows the evaluation of those parameters critical to their reservoir characterization. The determined reservoir properties investigated are lithology, depositional paleoenvironments, shale volume, porosity, fluid saturation and net pay thickness. As the analysis of reservoir pressure is essential to specify the driving mechanisms that control the behavior of fluids within reservoirs, pressure analysis identified the Alam El Bueib-3D reservoir to be partial water drive and Alam El Bueib-3E to be an active water drive. In addition, the pressure analysis identified two additional hydrocarbon-bearing reservoirs in the Alam El Bueib-3D. Stacking patterns of the Alam El Bueib-3D reservoirs are generally fining upward sequences reflecting fluvial to braided fluvial paleoenvironments. The Alam El Bueib-3E channel shows blocky patterns with sharp bases and tops diagnostic of distributary channels. Statistical analysis of core permeability and porosity values of the Alam El Bueib reservoirs indicate very good reservoir quality. Scatter diagrams of porosity values derived from core analysis for the AEB-3D and AEB-3E reservoirs reveal correlation coefficient (r) values of 0.93 and 0.64, respectively, indicating strong linear relationships. Plots of porosity values against permeability values also show strong linear relationships in all the reservoirs indicating that the AEB-3D and the AEB-3E are permeable and with strong pore communication. The permeability measurements indicate restricted reservoir heterogeneity as plots of vertical permeability values against horizontal permeability values exhibit linear trends. Altogether, the reservoir characterization of the Alam El Bueib reservoirs demonstrates their excellent potential for hydrocarbon production.  相似文献   
42.
This paper presents an ‘adaptive probability of crossover’ technique, as a variation of the differential evolution algorithm (ACDE), for optimal parameter estimation in the general curve-fitting problem. The technique is applied to the determination of orbital elements of a spectroscopic binary system (eta Bootis). In the ACDE, Varying the crossover probability rate (Cr) provides faster convergence than keeping it constant. The Cr is determined for each trial parameter vector (‘individual’) as a function of fit goodness. The adaptation automatically updates control parameter to an appropriate value, without requiring prior knowledge of the relationship between particular parameter settings and a given problem optimization characteristics. The presented analysis of eta Bootis derives best-fitting Keplerian and phasing curves. Error estimation of the optimal parameters is also included. Comparison of the results with previously published values suggests that the ACDE technique has a useful applicability to astrophysical data analysis.  相似文献   
43.
In Mabahiss Bay, north Hurghada City, Red Sea, Egypt, the bathymetric measurements show the irregular topography of the bottom. The bottom sediments are mainly composed of sand fractions (average 73.5%). Gravel and sand contents decrease with depth. On the other hand, silt and clay percents show indirect relation with depth. Abnormally, there are some spots found near the coast where the percent of both silt and clay increases. They also show carbonate sediments (average 90.15%) increasing toward the bay center. The narrow belt adjacent to the shore area has lower carbonate content reflecting the effect of clastic sediments input into the area. The sediments in the study area have more than one source as indicated from the results of the mechanical analysis. Wide range of grain size distributions, clay spots and low carbonate content near the shore indicate change in the nature of sedimentary environment (i.e., pollution) which may be caused by land filling accompanied with urbanization and building of touristic resorts and centers. The organic matter content in the sediments is much higher than that of the other areas in the Red sea (average 4.8%) with considerable accumulation in the inner most parts of the bay. This may be due to relative abundance of organic productivity, direct discharge of domestic waste in some spots along the coast of the study area, and/or local contamination of hydrocarbons (i.e., tar balls thrown out on shore by weak waves through the few inlets of the study area). The average concentrations of lead, nickel, copper, and cadmium are 44, 34, 51, and 3.1?ppm, respectively. The suggested origin of these metals is either organic (localized oil pollution), or using of antifouling and anticorrosive paints from fishing and tourist boats. Other metals, particularly manganese (average 77?ppm), cobalt (average 51?ppm), and zinc (average 16?ppm) as well as sodium (average 0.32%) and potassium (av. 0.10%) show a common trend of increasing concentration toward the outermost parts of the bay. Some parts along shoreline have increasing concentrations, even if these parameters having a common trend of increase towards the center of the bay. This may be either due to sewage and wastewaters discharges from many outlets of tourist centers and fishermen and cargo boats, and/or terrestrial sediments input. Direct comparison of the present levels of heavy metals in Mabahiss Bay with other published data along the Red Sea and Gulf of Suez shows that the study area has higher concentrations. Dredging, land filling, localized oil pollution, using of antifouling and anticorrosive paints from fishing and tourist boats (where the bay is used as harbor for many of fishermen and cargo boats), sewage, variable amounts of municipal wastewater from many outlets of tourist centers considered to be the sources of pollution within Mabahiss bay. There are many effects of pollution on Mabahiss Bay environment among which: (1) death of fishes, seaweeds, birds, marine mammals, etc., (2) damage of beaches and other recreational areas, (3) damage of marine ecosystem by eliminating or decreasing population of certain species, (4) hazard to human from ingesting contaminated food, and more.  相似文献   
44.
The oxidation of organophosphorus pesticides (OPPs), such as malathion and parathion, in aqueous solution was studied using conventional ozonation (O3), photolytic ozonation (O3/UV, O3/UV/H2O2), and heterogeneous catalytic ozonation (O3/TiO2/UV) processes. Experiments were performed in batch mode at laboratory scale and processes were compared in terms of disappearance kinetics. The best results of pesticide mineralization were obtained when TiO2 particles in combination with ozone (O3) and UV photolysis (λ = 254 nm) were applied. Decomposition of 99% of parent compounds were achieved in 10 min and oxon derivatives were completely removed in 30 min. The initial reaction rate increases linearly with increasing catalyst amount. Toxicity measurements of the treated solutions were carried out in order to evaluate the efficiency of the treatment methods. No detoxification was achieved for O3 and O3/UV applications. Heterogeneous photocatalytic ozonation was shown to be feasible for achieving complete decomposition of OPPs and their oxon intermediates.  相似文献   
45.
Coherent noise in land seismic data primarily consists in source‐generated surface‐wave modes. The component that is traditionally considered most relevant is the so‐called ground roll, consisting in surface‐wave modes propagating directly from sources to receivers. In many geological situations, near?surface heterogeneities and discontinuities, as well as topography irregularities, diffract the surface waves and generate secondary events, which can heavily contaminate records. The diffracted and converted surface waves are often called scattered noise and can be a severe problem particularly in areas with shallow or outcropping hard lithological formations. Conventional noise attenuation techniques are not effective with scattering: they can usually address the tails but not the apices of the scattered events. Large source and receiver arrays can attenuate scattering but only in exchange for a compromise to signal fidelity and resolution. We present a model?based technique for the scattering attenuation, based on the estimation of surface‐wave properties and on the prediction of surface waves with a complex path involving diffractions. The properties are estimated first, to produce surface?consistent volumes of the propagation properties. Then, for all gathers to filter, we integrate the contributions of all possible diffractors, building a scattering model. The estimated scattered wavefield is then subtracted from the data. The method can work in different domains and copes with aliased surface waves. The benefits of the method are demonstrated with synthetic and real data.  相似文献   
46.
The Dar El Beida area, situated in the Mitidja basin, in the north central Tellian Atlas is characterized by its Plio-Quaternary sediments. The site effect analysis in this zone surrounding Algiers city is very important. The soil is constituted from recent soft sediments capable of amplifying seismic motion. Indeed, the analysis thanks to the ratio H/V ambient vibration method confirms these assumptions. An electric resistivity tomography strengthened the results obtained from ambient vibration for site characterization. This demonstrates once again the more or less homogeneous character of formations in this area. However, strongly amplifying its sediments largely explains the seismic acceleration of 0.52 g recorded following the 2003 Boumerdes earthquake.  相似文献   
47.
Actinopterygian remains have been recovered from Upper Cretaceous (lower Campanian to lower Maastrichtian) marginal marine deposits of the Adaffa Formation in northwestern Saudi Arabia. The fossils comprise gars (Lepisosteidae), pachycormids (cf. Protosphyraena sp.), indeterminate pycnodontiforms, enchodontid teleosts (cf. Enchodus sp.) and other indeterminate Teleostei. This assemblage is significant because it includes a novel occurrence for the Middle East (Pachycormidae) together with taxa (Lepisosteidae, Pycnodontiformes, Enchodontidae) that have been previously recorded from Late Cretaceous faunas elsewhere in the Mediterranean Tethyan region.  相似文献   
48.
Biodiesel production is worthy of continued study and optimization of production procedures because of its environmentally beneficial attributes and its renewable nature. In Egypt, millions L. of oil used for frying foods are discarded each year into sewage systems. Thus, it adds to the cost of treating effluent or pollutes waterways. This study is intended to consider aspects related to the feasibility of the production of biodiesel from waste/recycled oils in an attempt to help reduce the cost of biodiesel and reduce waste and pollution coming from waste oils. The variables affecting the yield and characteristics of the biodiesel produced from used frying oil were studied, the achieved results were analyzed and a set of recommendations was proposed. From the obtained results, the best yield percentage was obtained using a methanol/oil molar ratio of 6:1, potassium hydroxide as catalyst (1%) and 65 °C temperature for one hour. The yield percentage obtained from waste vegetable oil was comparable to that obtained from neat vegetable oil which reached 96.15% under optimum conditions. From the results it was clear that the produced biodiesel fuel, whether from neat vegetable oil or waste vegetable oil, was within the recommended standards of biodiesel fuel.  相似文献   
49.
In central eastern Anatolia which is located between Eurasia and Africa, the study of basin developments between late Eocene and early Miocene is of great importance for understanding the process of the closure of the Neo-Tethys Ocean and the formation of strike-slip faults and regional uplift. To study these, three basins were selected: the Sivas-Erzincan, Gürün-Akkisla-Divrigi (GAD), and Malatya basins. The study proposes that the opening of the GAD basin played a key role in the formation of the Ecemis fault, which started developing at the end of early Miocene, and in mountain uplift. All these basins are situated on continental blocks and oceanic crust, arranged from north to south as the Sakarya continent, the Izmir-Ankara-Erzincan ocean (Northern Neo-Tethys), the Kirsehir continent, the inner Tauride ocean, the Munzur-Binboga block, the Maden (=Berit) ocean, the Bitlis-Pütürge block, the Çüngüs ocean and the Arabian continent.The findings indicate that late Eocene-early Miocene successions in these basins were not deposited in foreland basins formed in front of the thrust faults associated with the closure of the ocean, as stated in previous studies. Rather, they were deposited in forearc and backarc basins related to the subduction which was effective until the end of early Miocene. The Sivas-Erzincan and Malatya basins, located on the inner Tauride and Maden (=Berit) oceans, were forearc basins, while the GAD basin situated on the Munzur-Binboga block was a backarc basin. These basins have parallel developments up to the end of early Miocene. While marine sediments were deposited in the Malatya and Sivas-Erzincan basins between late Eocene and early Miocene, terrestrial units began to settle in the GAD basin from the late Eocene and the deposition there is continuous until the end of the early Miocene.Collision of the Arabian and the Anatolian plates at the end of early Miocene (16-18 Ma) produced the left-strike slip Ecemis fault zone, which caused the lateral slip of sedimentary units in the Sivas-Erzincan and GAD basins over hundreds of kilometers. This event produced the first westward tectonic escape of the Anatolian plate prior to the north Anatolian fault (NAF) and the east Anatolian fault (EAF). The Gürün region located in the GAD basin was exhumed in late Miocene and this basin was broken. The Gürün region, which remains on the rising part of the Munzur-Binboga block, is not a different basin as stated earlier, but it is a part of the GAD basin, representing the central part of the GAD basin lake, as indicated by the fine grained deposits (limestones and clay) that occur in the Gürün area.  相似文献   
50.
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