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Геоморфология

Расширенный поиск
№ 3 (2003)

Общетеоретические статьи

3-9 217
Аннотация
About 6000 height level data of the West Siberian Plain (h max and h min in every cell of 20' x 30') were used in analysis. The northern part the plain has meridional strike of large landforms, its prevailing height level is 55-75 m; the southern part has diagonal strike and prevailing level 95-115 m. The average height of the plain is 96 m - 28 m less than that of the Russian Plain. Height histogram of West Siberia has 2 modes, while the Russian Plain has 4. On the whole relief of West Siberia is closer to graded profile, than that of the Russian Plain, though it is younger than the latter. Positive neotectonic movements being more active and differentiated in the Russian Plain may be the cause for such discrepancy.
10-25 198
Аннотация
Geomorphologic data, obtained by the author from field researches, literature and maps, were matched with material on tectonic splitting of lithosphere, lateral fault displacements, seismicity, neotectonic movements, young volcanism, and crust thickness. As a result of such morphotectonic analysis geodynamic model of Altai mobile zone was compiled. The model gives consistent explanation of neotectonic development of this area. Vertical movements of crust blocks, being the base for mountain relief building, appeared to be the sequence of lateral movements of much greater amplitude. The pattern of N-Q faults may be thoroughly explained by major strike-slips, running through the whole mountain system, and by branch structures of compression and extension.

Экологическая и прикладная геоморфология

26-35 188
Аннотация
Hazardous geomorphic processes such as landslides and collapses of rocks into reservoir are described. They lead to formation of large waves and overflow, which in turn may cause dam destruction. Factors that may activate such processes, for instance seismicity, atmospheric conditions, karst phenomena, water level fluctuations, abrasion are characterized. Comparative evaluation of land losses caused by the breakdown of various reservoirs bank is given. Possible growth of exogenous processes due to descent of water in the reservoir of Saratov hydroelectric plant is discussed.

Научные сообщения

36-43 186
Аннотация
During the sea-level rise lagoon formation is taking place if the dip of the coastal land is less than the dip of the offshore. Under such condition lagoon and coastal bar appear simultaneously. They are genetically associated and form joint transgressive system. The sediments of bar and lagoon are of different types, though their accumulation occurs at the same hypsometric level. Thence, lagoon sediments in the transgressive train have a seat rock from previous regressive phase; they are overlay by shelly and sandy loose beach deposits of the same transgressive stage as lagoon loam and have the same age. Such paragenesis should be taken into account while interpreting geological data and paleogeographical reconstructing.
44-53 197
Аннотация
Several morphologic types of glacial landforms in the vicinity of Teletskoye Lake were distinguished in the process of geomorphic mapping. The plan patterns of these forms, their heights, relation to other forms are described. On the basis of geomorphologic structure of region and quaternary deposits data glacial landforms were attributed to two glacial epochs. Glacial valleys, which lay out at height 900-1900 m, have been strongly changed. It was impossible to distinguish certain morphological types among them; they were conditionally attributed to Middle Pleistocene. Valleys, which are in a state of fair preservation, lay out at height 1900-2000 m and have their bottoms at height 1700-1900 m. These valleys were formed during the last - Late Pleistocene - glaciation. Two subtypes of valleys of this age were distinguished. There are no morphological evidences of glacial existence in the lake basin itself.
54-61 222
Аннотация
Channel deformation rate at different phases of water regime was analysed. Conditions of sediment accumulation and breaking-up were determined and mobility of sediment was evaluated. The phase of maximum channel deformation intensity corresponds to the moments of channel-forming discharge.
62-75 189
Аннотация
The recent Kolyma River drainage system is not uniform in structure. The tectonic uplift of Upper and Middle Kolyma area occurred as a background process through the Cenozoic, and the climatically forced incision and accumulation were the most critical factors affecting the fluvial series structure and sediment thickness. The impact of climatic factor is apparent throughout the whole Kolyma basin. Tectonic processes and repeated transgressions caused repeated transformations of Lower Kolyma channel system. Submerged part of Kolyma valley has a compound character; it became a unified fluvial system only in the Pleistocene.
76-91 193
Аннотация
Several examples of buried erosion landforms uncovered in the Lebedinsky quarry (Kursk magnetic anomaly) were examined. They are situated within the valley-balka slope of river Oscolets and adjacent lower part of watershed. The structure of sediments that fill the depressions represents full erosion cycle corresponding to climatic rhythm: the end of Moscow glaciation, Miculino interglacial, beginning of Valdai glaciation. Taken as a whole erosion cycle consists of the incision stage (arid climate - periglacial, then interglacial), stabilisation stage (humid climate of interglacial and Valdai interstadials), accumulation stage (cold humid and then periglacial climate). Detailed picture of erosion cycle is much more complex and has hierarchical structure connected with hierarchy of Pleistocene climatic rhythms.
92-96 168
Аннотация
The paper represents the author's account of visiting Apennines, participation in the international symposium, and learning the relief and traces of hazardous processes on mountain slopes during the scientific excursion.


ISSN 0435-4281 (Print)