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We examine the intrasecular morphodynamics of the Irkut river within the Tunkinskaya depression and the associated partitions between depressions. An analysis is made of the changes in the channel pattern in plan, and a typization is provided for the channel processes for three time intervals: 1914, 1975 and 2015. We identified eleven morphodynamically uniform reaches of the channel: three, one and seven of them are of the adapted, incised and broad-floodplain types, respectively. The types of morphodynamical development of the river are systematized, and reaches with a different degree of deformation are identified within the most mobile broad-band segment of the river in conditions of free meandering. It is ascertained that the reaches of the braided type and the reach with sharp loop-like bends are the most stable, which is, in either case, due to the consolidation of vegetation by the high floodplain which made it possible to stabilize the movement of the channel in plan. The most strongly altered reaches are determined, where river channel displacements were accompanied by a complete change of the morphodynamical types of bends; the macrobends mainly experienced a regular breakthrough or were complicated by lower-order bends. We identified the reaches with lower-order (local) changes where the development of the bends (for the most part, of the loop-like type) changed into a new evolutionary cycle). We determined the role played by the influence of the territory’s geologo-geomorphological structure, hydrological conditions and natural processes of channel evolution on the dynamics of homogeneous reaches, and on morphological changes within them. The period of the most significant channel deformations, from 1914 to 1976, was determined, which is accounted for by an enhancement in anthropogenic pressure and by the associated increase in suspended load, and the period of decrease in the magnitude of manifestations of channel deformations from 1976 to 2015. 相似文献
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Presented are the technique and results of studying the landscape structure of the north-west of Western Siberia on the basis of the Hansen mosaic dataset consisting of elements covering the entire territory of the Earth. To study this area used a synthesis of classical methods of thematic system mapping as described in the doctrine of geosystems of V. B. Sochava, and automated interpretation of remote sensing data and mapping using GIS technologies. The method of geoinformational mapping of the landscape structure with the use of MultiSpec and Quantum GIS software programs for the purpose of drawing up real-time raster landscape maps is shown. In drawing up the map and the legend, the principle of geomic system-hierarchical representation of the territory as a complex multi-level “bottom-up” structure from topological-level geosystems (groups and classes of landscape facies) to regional-level geosystems (geoms, groups and classes of geoms) was used. Compilation of operational raster landscape maps of the north-west of Western Siberia involved multilevel automated interpretation of the Hansen mosaic dataset and mapping of areas (clusters) on images with different brightness characteristics, with the landscape structure of key areas and stationary physical and geographical profiles. A characteristic of this approach also implies using a dynamic classification of geosystems based on the study of their variable states. Such an approach permits a monitoring of changes in landscape structure and its areas and the intensity of anthropogenic impacts on forest and marsh landscapes, and determination of permissible pressure on geosystems in areas with high technogenic pressure of the oil and gas complex represented by the north-west of Siberia. An automated processing of data based on a supervised classification of territorial objects allows for the elimination of inaccuracies arising in visual image interpretation. Raster landscape maps can be used both for a further generation of vector maps and as a real-time information base for purposes of environmental management and protection. 相似文献
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V. I. Silaev G. A. Karpov L. P. Anikin V. N. Filippov V. A. Petrovsky A. E. Sukharev Yu. S. Simakova 《Doklady Earth Sciences》2017,476(1):1048-1053
The results of X-ray structural, electron-microscopic, and X-ray spectral microprobe studies of Al-based metal solid solutions that underwent nuclear disintegration and that were discovered in nature for the first time are presented. Based on the similarity to technical counterparts, it is suggested to recognize the previously unknown alloys as natural duralumin. 相似文献
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Semenov M. Yu. Snytko V. A. Semenov Yu. M. Silaev A. V. Semenova L. N. 《Doklady Earth Sciences》2019,486(2):699-705
Doklady Earth Sciences - The metal composition of water and bottom sediments of the southern tributaries of Lake Baikal has been studied, and the water migration coefficients have been calculated.... 相似文献
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V. I. Silaev M. Yu. Sokerin V. D. Tikhomirova Yu. V. Glukhov V. P. Lyutoev 《Lithology and Mineral Resources》2000,35(4):319-330
We found and studied the phosphate and ferromanganese mineralization in the Holocene alluvium at upper reaches of the Severnaya
Dvina River. Possible sources and accumulation mechanisms of manganese during the aquagene-fluvial hydroxide formation are
first discussed.
The report at the XIII Geological Congress of the Komi Republic, January 26, 1999. 相似文献