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1.
October Field is one of the most prolific offshore oil fields in the Gulf of Suez of Egypt. It consists of a number of marine platforms and produces oil from different reservoirs of different geological ages from the Lower Cretaceous to the Miocene. The aim of this study was to enhance a seismic-log evaluational procedure to evaluate the Miocene-aged Asl and Hawara Formations which encounter the main hydrocarbon and source rock potentials in the area North of October Oil Field. The well logging data, the borehole seismic data, and the velocity surveys are all used in this study. A number of synthetic seismograms are constructed and interpreted together with the deduced seismic impedance and reflection coefficient data for many wells in the study area. In addition, a comprehensive velocity analysis is performed using the seismic times and the computed average and interval velocities. These seismic-derived parameters are primarily used in recognizing and locating precisely the marl and sand sections of Asl Formation which show low to middle amplitudes. Furthermore, a quantitative well logging analysis is carried out over Asl and Hawara Formations to shed light over their hydrocarbon potentiality. Good oil saturation is exhibited by the Asl sand section which reaches to more than 90% in the southern parts of the study area. The petrophysical characters of this sand are very good in terms of good effective porosity (9% to13%), low shale volume (V sh?<?5%), and high oil saturation (S h?>?85%). The sections of the Asl marl and the Hawara shale on the other hand are considered completely wet. An integrated model making use of the seismic- and log-derived properties is applied over the two studied formations for better understanding the reservoir of interest. Many relations are constructed between velocity, seismic impedance, and the rock pore spaces on one hand and between the velocity, lithology, and fluid content on the other hand. This study revealed that the sand section attains very good oil-bearing potentiality in the study area and proved that the application of an integrated model of the log- and seismic-derived properties led to an enhanced evaluation of the Asl and Hawara Formations, good discrimination between their lithological components besides precise differentiation from the overlying Middle to Late Miocene sections.  相似文献   
2.
The results of investigating the data of stationary and field observations in the epicentral zone of the Kultuk earthquake of August 27, 2008 with M w = 6.3 localized south of Baikal are presented. The seismic activation amounting to 1790 aftershocks with K p ?? 4 (M w ?? 0.9) affected a part of the general fault bounding the southwestern coast of the lake and shallower intrabasin structures. It was established through the cluster analysis that the main shock was located at the periphery of the cloud of the concentrated seismicity component, and three main clusters reflecting a complex character of rupture in the earthquake source were identified in the zone of aftershocks. Owing to a high accuracy of aftershock hypocenters determinations (ERZ ?? 1.2 km), the local character of the seismisity-generating zones was revealed. Based on the method of mapping seismic regime parameters, it was established that zones of reduced fractionality are recognizable in the central part of the source area; in this case, the entire periphery, except for the southeastern direction (where the main shock epicenter is located), is characterized by a high fractionality, which also points to the complex character of the rupture in the source. On the whole, the aftershock sequence under consideration showed the activation of the southwestern flank of the Southern Baikal region, which remained passive for more than one century, and demonstrated destructive features of the Earth??s crust.  相似文献   
3.
Most of the studies related to the modeling of masonry structures have by far investigated either the in‐plane (IP) or the out‐of‐plane (OP) behavior of walls. However, seismic loads mostly impose simultaneous IP and OP demands on load‐bearing or shear masonry walls. Thus, there is a need to reconsider design equations of unreinforced masonry walls by taking into account bidirectional effects. The intent of this study is to investigate the bidirectional behavior of an unreinforced masonry wall with a typical aspect ratio under different displacement‐controlled loading directions making use of finite element analysis. For this purpose, the numerical procedure is first validated against the results of the tests on walls with different failure modes conducted by the authors. Afterward, the response of the wall systems is evaluated with increasing top displacement having different orientations. A set of 19 monotonic and three cyclic loading analyses are performed, and the results are discussed in terms of the variation of failure modes and load–displacement diagrams. Moreover, the results of wall capacity in each loading condition are compared with those of the ASCE41‐06 formulations. The results indicate that the direction of the resultant force, vectorial summation of IP and OP forces, of the wall is initially proportional to the ratio of stiffness in the IP and the OP directions. However, with the increase of damage, the resultant force direction inclines towards the wall's longitudinal direction regardless of the direction of the imposed displacement. Finally, recommendations are made for applicability of ASCE41‐06 formulations under different bidirectional loading conditions. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
4.
Stability is always the most important problem after high slope was excavated. The study analyzed the stress and strain inside the slope by Finite Element Method (FEM) and carried through stress distribution and failure zone, then analyzed the stability of the slope using three different methods and came to the conclusion that it is in unstable condition, so the designed retaining wall was put forward which makes the slope stable.  相似文献   
5.
According to topography of Yemen,most areas and villages are located at obligated crest,toe of mountain and under cliffs.Therefore Al-Huwayshah consisting of Tawilah sandstone group is characterized by steep slope reach to 90° in some areas.This area is affected by strong tectonic movements and faults that occurred during the geological epochs.This effect enhances to find out fractures and joints as well as the rocks become brittle and ready to slide depending on the position of area.And there are some frac...  相似文献   
6.
A field work has been carried out to identify the occurrence of oil and oil products pollution in mangrove sediment from Red Sea of Yemen. The concentration of total petroleum hydrocarbons is from 700ng/g at Kamaran Island station to 400 ng/g at Al-Hodiedah station, and the total organic carbon (TOC) in samples ranges from 0. 07% at Dhubab station to 0. 03% at Kamaran Island station. This pollution is as a result of localized oil pollution and/or heavy ship traffic in the Red Sea and Gulf of Aden.  相似文献   
7.
According to topography of Yemen, most areas and villages are located at obligated crest, toe of mountain and under cliffs. Therefore Al-Huwayshah consisting of Tawilah sandstone group is characterized by steep slope reach to 90° in some areas. This area is affected by strong tectonic movements and faults that occurred during the geological epochs. This effect enhances to find out fractures and joints as well as the rocks become brittle and ready to slide depending on the position of area. And there are some fractures and joints on the surface of the areas due to tectonic movement associated with opening the Red Sea and Gulf of Aden. The rainfalls, fractures, joints, earthquakes, gravity, vegetations, temperatures and human activities play a big role in the processes of rockfalls and landslides in this area. All those factors are considered as the basic causes and catalyzed factors for occurrence of rockfall in the studide area. In addition, the authors carried out laboratory test for many rock samples to get the physical properties of the rocks.  相似文献   
8.
A field work has been carried out to identify the occurrence of oil and oil products pollution in mangrove sediment from Red Sea of Yemen. The concentration of total petroleum hydrocarbons is from 700 ng/g at Kamaran Island station to 400 ng/g at Al-Hodiedah station, and the total organic carbon ( TOC) in samples ranges from 0.07% at Dhubab station to 0.03% at Kamaran Island station. This pollution is as a result of localized oil pollution and /or heavy ship traffic in the Red Sea and Gulf of Aden.  相似文献   
9.
The chemical composition of several thermal springs around Changbaishan area has been investigated. Cenozoic basaltic rocks are widely distributed in Northeast China and geothermal characteristics have been described. About one hundred hot springs exist around Changhaishan Volcano at the border between China and D.P.R.Korea with high temperature about 82~C. The pH values of the spring water range from 6.9 to 7.1 and the total flow rate is about 4.8 L/sec. The chemical composition of the thermal springs is sodium carbonate; the high-mineral contents of thermal water are believed to have medicinal properties. Bathhouses are already built along the hot springs to take the advantage of the supposed healing properties. The high quality of those hot springs is believed to be utilitized for mineral water. The chemical equilibrium temperatures were estimated at about 160℃ based on the Na-K-Ca geochemical thermometer.  相似文献   
10.
We present the INTEGRAL and RXTE X-ray observations of XTE J1550-564, a Galactic microquasar and a black hole candidate, during its outburst in the spring of 2003. The source during the outburst was in a canonical hard state, and its spectrum remained constant in both the rise and decay phases.  相似文献   
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