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101.
102.
We generalize our results of a second order Jupiter-Saturn planetary theory to be applicable for the case of the four major planets.We use the Von Zeipel method and we neglect powers higher than the third with respect to the eccentricities and sines of the inclinations in our expansions. We consider the critical terms as the only periodic terms. 相似文献
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El Nour AH 《GeoJournal》1989,18(4):369-377
The study of urbanization has, in recent years, assumed increasing importance in developing countries not only because these countries are in the process of facing rapid urbanization, but also because the process of urbanization has been recognized as a part of a larger process of economic and social change which is affecting the rural areas. 相似文献
107.
Karstified features and surficial calcareous crust (caliche) develop on the upper most surfaces of the Middle Miocene rocks in the area between Quseir and Mersa Alam along the Red Sea coast, Egypt. Detailed studies of the caliche profile revealed various textures and fabrics denoting a cyclicity in deposition as well as diagenetic differentiation crystallization and deformation. The occurrence of these caliche deposits suggest that the Middle Miocene rocks in the study area have been subjected to alternating periods of rainfall and intense evaporation.
Zusammenfassung Karstphänomene und Kalkkrusten (Caliche) haben sich auf den Oberflächen der Gesteine des Mittelmiozäns im Gebiet zwischen Quseir und Mersa Alam entlang der Küste des Roten Meeres in Ägypten entwickelt. Eingehende Untersuchungen von Kalkkrusten Profilen lassen unterschiedliche Strukturen und Gefüge erkennen, die sowohl zyklische Bildung belegen als auch diagenetische Kristallisations-Differentiation und Deformation. Das Auftreten dieser Caliche-Bildungen legt nahe, daß die mittelmiozänen Gesteine im Untersuchungsgebiet abwechselnd regenreichen Perioden und solchen mit starker Evaporation ausgesetzt waren.
Résumé Des structures karstiques et des croûtes calcaires superficielles (caliches), se sont formées à la surface des roches du Miocène moyen dans la région comprise entre Ouseir et Mersa Alam, le long de la côte de la mer Rouge, en Egypte. L'étude détaillée de profils de la caliche révèle des structures variées qui indiquent un dépôt cyclique ainsi qu'une cristallisation différentielle et une déformation diagénétique. La présence de tels dépôts de caliche suggère que les roches du Miocène moyen de cette région ont été soumises alternativement à des périodes de pluie et d'évaporation intense.
Quseir Mersa Alam — . , , , , . , .相似文献
108.
Summary The Reitan (1963) regression equation of the form lnw =a +bT
d
has been examined and tested to estimate precipitable water vapor content from the surface dew point temperature at different locations. The results of this study indicate that the slopeb of the above equation has a constant value of 0.0681, while the intercepta changes rapidly with latitude. The use of the variable intercept technique can improve the estimated result by about 2%.With 6 Figures 相似文献
109.
Mineralogical data, coupled with whole-rock major and trace element data of mafic xenoliths from two occurrences of the Egyptian Tertiary basalts, namely Abu Zaabal (AZ) near Cairo and Gabal Mandisha (GM) in the Bahariya Oases, are presented for the first time. Chemically, AZ basalts are sodic transitional, while those of GM are alkaline. In spite of the different petrographic and geochemical features of the host rocks, mafic xenoliths from the two occurrences are broadly similar and composed essentially of clinopyroxene, plagioclase, alkali feldspar, and Fe–Ti oxides. The analytical results of host rocks, xenoliths and their minerals suggest that the xenoliths are cognate to their host magmas rather than basement material. The mafic xenoliths are olivine-free and contain alkali feldspar contrary to the phenocryst assemblage of the host rocks, confirming that they are not cumulates from the host magma. The geochemical and mineralogical characteristics show that the precursor magmas of these xenoliths are more fractionated and possibly contaminated compared to those of the host rocks. Estimated crystallization conditions are 1–3 kbar for xenoliths from both areas, and temperature of 950–1100 °C vs. 920–1050 °C for AZ and GM, respectively. These cognate xenoliths probably crystallized from early-formed, highly-fractionated anhydrous magma batches solidified in shallow crustal levels, possibly underwent some AFC during their ascent, and later ripped-up during fresh magma pulses. The xenoliths, although rare, provide an evidence for the importance of crystal fractionation at early evolution of the Egyptian Tertiary basalts. 相似文献
110.
H. Evangelista D. Godiva A. Sifeddine Z. M. A. N. Leão N. R. Rigozo B. Segal T. Ambrizzi M. Kampel R. K. P. Kikuchi F. Le Cornec 《Climate Dynamics》2007,29(7-8):869-880
Physical and biological changes in the marine environment, induced by oceanic-atmospheric processes, can be imprinted in massive coral skeletons. Herein, we present an evidence of potential El Niño impacts at the Southwestern South Atlantic Ocean (SWSA) inferred from the sclerochronology of the reef coral Favia leptophylla. The application of spectral analysis (wavelet decomposition and the iterative regression) to coral growth length and to meteorological-oceanographic parameters (air temperature, sea surface temperature and precipitation) as well as to Southern Oscillation Index (SOI) and solar irradiation indicated a major significant inverse relationship between SOI and coral growth length at the 4–8 years frequency band. We propose here that coral growth length from the SWSA could be affected by El Niño Southern Oscillation (ENSO) events through an “atmospheric bridge”, in contrast to its direct effect at the Pacific Ocean, related to the increase in sea surface temperature. 相似文献