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排序方式: 共有348条查询结果,搜索用时 31 毫秒
91.
92.
Deep petroleum occurrences in the Lower Kura Depression, South Caspian Basin, Azerbaijan: an organic geochemical and basin modeling study 总被引:1,自引:0,他引:1
Sedat Inan M. Namik Yalin Ibrahim S. Guliev Kerem Kuliev A. Akper Feizullayev 《Marine and Petroleum Geology》1997,14(7-8)
High sedimentation rates (as much as 2500 m/Ma) during Pliocene-Pleistocene, with a resultant undercompacted section as thick as 10,000 m, and lower than normal geothermal gradients are the main characteristics which have created all the means for generation and preservation of oil at deep layers in the Lower Kura Depression.Oils collected from eight different oil fields for analyses seem to have originated from a common source rock which probably is clastic, deposited in relatively subanoxic to suboxic transitional marine environment receiving low to moderate input of terrestrial organic matter.Oils from shallow (< 3000 m) and cold (< 70–80°C) reservoirs have been altered to various extent by bacterial activity.A computer-aided basin modeling study has been carried out to outline the spatial variation of the oil window and thus help in further identification of possible source rocks for the reservoired oil in the Lower Kura Depression. Results suggest that the potential hydrocarbon source horizons of the Miocene and Pliocene Red Bed Series of the so called Productive Succession are, even at depocenter areas, immature with respect to oil generation, and thus, are very unlikely to have been source rocks for the reservoired oils. However, the Oligocene-Lower Miocene Maykop rocks are marginally mature to mature depending on locality and the Eocene and older rocks are mature with respect to oil generation at all representative field locations. Oil generation commenced at the end of Pliocene and continues at present at depths between 6000 and 12,000 m.An unusually deep (> 10,000 m) oil window in the depocenter areas has been caused by the depressed isotherms due to extremely high sedimentation rates (up to 3000 m/Ma) for the last two million years. The main phase of oil generation is taking place at depths greater than what most of the wells in the study are have reached. 相似文献
93.
Sharareh Pourebrahim Mehrdad Hadipour Mazlin Bin Mokhtar Mohd Ibrahim Hj Mohamed 《Ocean & Coastal Management》2010,53(9):544-551
The coastal lands are very important boundaries in the natural system. But these areas are under pressure that has threatened their health by short-sighted planning policies. The management options have focused on economic production and human benefits rather than the natural systems that guaranty sustainability of them. Evaluation of sustainability in coastal lands needs some critical criteria and indicators. The purpose of this paper is to demonstrate an innovative reliable method for identification of the most important criteria and indicators using multi criteria techniques, especially the Analytic Network Process (ANP). Analytic Network Process as a new approach has potential to be applied into the field of coastal land use development. This is the first time ANP has been used for criteria selection to ensure sustainability in coastal land use planning. The integration of social, economic and environmental criteria within the planning framework in this paper has provided a holistic approach for integrated coastal land use development. 相似文献
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In this study, we investigate the interplanetary consequences and travel time details of 58 coronal mass ejections (CMEs) in the Sun–Earth distance. The CMEs considered are halo and partial halo events of width \({>}\,120\)°. These CMEs occurred during 2009?–?2013, in the ascending phase of the Solar Cycle 24. Moreover, they are Earth-directed events that originated close to the centre of the solar disk (within about \(\pm30\)° from the Sun’s centre) and propagated approximately along the Sun–Earth line. For each CME, the onset time and the initial speed have been estimated from the white-light images observed by the LASCO coronagraphs onboard the SOHO space mission. These CMEs cover an initial speed range of \({\sim}\,260\,\mbox{--}\,2700~\mbox{km}\,\mbox{s}^{-1}\). For these CMEs, the associated interplanetary shocks (IP shocks) and interplanetary CMEs (ICMEs) at the near-Earth environment have been identified from in-situ solar wind measurements available at the OMNI data base. Most of these events have been associated with moderate to intense IP shocks. However, these events have caused only weak to moderate geomagnetic storms in the Earth’s magnetosphere. The relationship of the travel time with the initial speed of the CME has been compared with the observations made in the previous Cycle 23, during 1996?–?2004. In the present study, for a given initial speed of the CME, the travel time and the speed at 1 AU suggest that the CME was most likely not much affected by the drag caused by the slow-speed dominated heliosphere. Additionally, the weak geomagnetic storms and moderate IP shocks associated with the current set of Earth-directed CMEs indicate magnetically weak CME events of Cycle 24. The magnetic energy that is available to propagate CME and cause geomagnetic storm could be significantly low. 相似文献
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98.
C. D'Amico H. A. Ibrahim Prof. F. P. Sassi 《International Journal of Earth Sciences》1981,70(3):882-896
A sequence of events which has been recognized in the two basement regions of Somalia is outlined on the basis of new field and petrographic data and pre-existing published and unpublished reports. The evolution of the Somalian basement took place during the Pan-African event, However, much detailed work is necessary before the history of the basement can be integrated into the more detailed Pan-African picture recognized in the neighbouring regions.
Zusammenfassung Eine Folge von Ereignissen, die sich in den zwei Basement-Regionen Somalias erkennen lie\en, wird auf der Basis neuer GelÄnde- und petrographischer Daten und früherer publizierter und nicht publizierter Berichte umrissen. Das Basement von Somalia entwickelte sich wÄhrend des Panafrikanischen Ereignisses.Viel Detailarbeit ist jedoch noch zu leisten, bis die Geschichte des Basements in das detailliertere Bild Panafrikas, wie es aus den Nachbarregionen gewonnen wurde, integriert werden kann.
Résumé Dans les deux régions de la Somalie ou le socle affleure, on a reconnu une succession d'événements sur la base de nouvelles données géologiques et pétrographiques et de travaux pré-existants, publiés et non publiés. L'évolution du socle de la Somalie se déroula pendant l'événement Pan-Africain. Toutefois, beaucoup de travail doit Être encore fait avant que l'histoire du socle somalien puisse Être intégrée dans un cadre Pan-Africain plus détaillé, tel qu'on le connait dans les régions voisines.
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99.
Ahmed Abdulkareem Ahmed Biswajeet Pradhan Maher Ibrahim Sameen Ali Muayad Makky 《Arabian Journal of Geosciences》2018,11(11):280
This study proposed a workflow for an optimized object-based analysis for vegetation mapping using integration of Quickbird and Sentinel-1 data. The method is validated on a set of data captured over a part of Selangor located in the Peninsular Malaysia. The method comprised four components including image segmentation, Taguchi optimization, attribute selection using random forest, and rule-based feature extraction. Results indicated the robustness of the proposed approach as the area under curve of forest; grassland, old oil palm, rubber, urban tree, and young oil palm were calculated as 0.90, 0.89, 0.87, 0.87, 0.80, and 0.77, respectively. In addition, results showed that SAR data is very useful for extracting rubber and young oil palm trees (given by random forest importance values). Finally, further research is suggested to improve segmentation results and extract more features from the scene. 相似文献
100.
F. N. Ibrahim Prof. Dr. 《GeoJournal》1991,25(1):13-18
Today, more than one third of the population of Khartoum are southerners who migrated to the capital mainly in the last eight years because of the civil war. Their conditions are very bad. They are starving in the town, for most of them are unemployed and have no means of living. Their housing conditions in the shanty towns are deplorable. The development of squatter settlements and the struggle for the demarcation of quarters are delineated in this paper. In Khartoum the southerners develop a strong sense of solidarity and develop a growing supra-southern-Sudanese identity replacing the former ethnic and local identities. 相似文献