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681.
The paper describes the thermohaline structure of the Izmir waters obtained from three CTD-surveys carried out in different seasons of 1994. Also, the mechanisms responsible for the formation of the regional peculiarities and the variability of the temperature/salinity field and examined. The results of diagnosis and adaptation computations of the three-dimensional water circulation are analysed, applying a numerical model and CTD-data. Translated by Vladimir A. Puchkin.  相似文献   
682.
683.
The surge phenomena and currents in the Azov Sea caused by variable winds in the presence of stationary currents are studied by using a three-dimensional nonlinear mathematical model. The specific features of the transformations of impurities in the water area of the Azov Sea under the joint action of stationary and nonstationary winds are investigated. On the basis of the results of numerical calculations, we make conclusions concerning the dependence of the period of dissipation of impurities on the wind velocity and the location of the regions with impurities. It is shown that the variable wind significantly increases the deviations of the sea level and the area of distribution of the impurity as compared with the action solely of the stationary currents.  相似文献   
684.
Within the framework of the linear theory, by using numerical methods, we study the free and forced waves in a bounded basin whose geometric characteristics approximately correspond to Lake Donuzlav. The oscillatory motions of the liquid at the exit of the lake are regarded as a driving force. The dependences of the amplitudes of generated waves on the parameters of the driving force are analyzed. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 1, pp. 37–51, January–February, 2005.  相似文献   
685.
The images of the western part of Olympus Mons and adjacent plains acquired by the HRSC camera onboard the Mars Express spacecraft were studied. The morphology, topography, and color of the surface were investigated. The surface age was determined by the frequencies of impact craters. The examination of the HRSC images combined with an analysis of the MOC imagery and MOLA altitude profiles have shown that the Olympus Mons edifice, at least in its western part, is composed of not only lavas but also of sedimentary and volcanic-sedimentary rocks consisting of dust, volcanic ash, and, probably, H2O ice that precipitated from the atmosphere. These data also indicate that glaciations, traces of which are known on the western foot of Olympus Mons (Lucchitta, 1981; Milkovich and Head, 2003), probably also covered the gentle upper slopes of the mountain. It is probable that the ice is still there, protected from sublimation by a dust blanket. Confirming (or rejecting) its presence is a challenge for the scheduled radar sounding with the MARSIS instrument mounted on the Mars Express spacecraft as well.__________Translated from Astronomicheskii Vestnik, Vol. 39, No. 2, 2005, pp. 99–116.Original Russian Text Copyright © 2005 by Basilevsky, Neukum, Ivanov, Werner, S. van Gesselt, Head, Denk, Jaumann, Hoffmann, Hauber, McCord, the HRSC Co-Investigator Team.  相似文献   
686.
Some results derived in the course of exploration of seawater dynamics over the Mediterranean and Black Seas shelf, conducted in the framework of the Black Sea and Internal Waves projects during the summer of 1991, are described.Translated by V. Puchkin.  相似文献   
687.
High-manganese kutnohorite was found in the surface layer of bottom sediments of the South Caspian basin by the method of X-ray diffraction for the first time. Bottom sediments were collected by a multicorer during the 39th voyage of R/V Rift in 2012. Study of the samples by a complex of methods (X-ray diffraction, scanning electron microscopy, atomic absorption, and analysis of the carbon isotope composition) allowed us to attribute kutnohorite to autigenic minerals of the early stage of diagenesis.  相似文献   
688.
Doklady Earth Sciences - Dynamic processes and features of transformation of pollution in the Sea of Azov, caused by the action of a real wind and atmospheric pressure in the presence of stationary...  相似文献   
689.
Geoinformational analysis shows that the fraction of lands that are optimal for farming of the main crops in Russia is about 10% of the available land at best (for summer wheat, buckwheat). For the majority of other crop cultures, this value is a few percent at most. The available resources are used very incompletely. The index of completeness of land resource potential use is no more than 10% for the majority of crops. Only in the case of soy are the available resources almost completely involved, whereas available land resources of winter wheat, grain maize, and sunflowers are used at 20–30%.  相似文献   
690.
Analysis of detailed bathymetric charts and records of phototelevision profiling over the surfaces of the guyots of the Magellan Seamounts reveals many cones and domes. Their diameters and heights vary from a few hundreds of meters to 10 km and from 30 to 350 m, respectively. The age generations of these mesomorphic structures correspond to the Campanian–Maastrichtian, Late Paleocene–Eocene, and Miocene. The formation of complicating volcanic edifices is most likely determined by late phases of volcanic activity related to differentiation of magmatic melts. At the same time, the tectonic factor responsible for their formation is also sufficiently well evident: volcanic edifices on plateau summits are associated spatially with linear morphostructures and lineaments.  相似文献   
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