The main postulates and conceptions of modern geomorphology are discussed, considering the latter as the science of continuous-discontinuous development of landforms. In the later years the traditional evolution-genetic paradigm is complemented with the growing attention to anthropogenic and ecological geomorphology and to the most general laws of universe and human's place in it.
The notions "channel processes" and "manifestation modes of channel processes" are founded. The channel processes being the complex of phenomena related to interaction between stream and channel, to erosion, transportation and accumulation of sediments, differ from each other at large, medium and small rivers in the plain conditions. It allows classifying processes under the size of the river. Rock channels take a particular place in such classification.
The erosion and accumulation phases of river basin action were distinguished as a result of nearly 30-year stationary field study. The phase changes are affected by 11-year cycle of solar activity, which causes the changes in humidity and hence in the exogenous processes activity. The 20th cycle corresponds to the phase of accumulation, the 21st - to the phase of erosion.
Дискуссии
Stability and flexibility of geomorphic system form the complex of characteristics, which make possible to evaluate ecological and engineering properties of given area. Authors suggest the term "adaptation properties" of geomorphic system. The terms "engineering properties of relief", "ecological properties of relief" are posed to discussion.
Методика научных исследований
The capability of GIS-technology in mountain relief analysis is considered. The model topography profile has satisfactory fitness with that obtained by GPS. Interactive analysis of model fields of relief characteristics is described with the purpose of geomorphic complexes' identification. Morphological structure of Seminsky pass topography was analyzed by this method, using model and field data.
Научные сообщения
The formation of ring shaped morphostructures of the region may be connected with deep faults and heat flow activization.
The conception of lacustrine morpholithogenesis is worked out. Conditions, factors, related processes of lake basin formation are discussed. Two stages of lacustrine morpholithogenesis - transgressive and regressive - are described.
Discontinuous change of denudation basis in the uprising mountains of Tien-Shan leads to the formation of terrace sequences and contiguous slopes common to large territory. Carst caves "Obi-Rakhmat" and "Pal'tau" are located between levels of second and third terraces, what unambiguously evidences that they were already used by human after cutting of the river into the surface of third and accumulation of the second terraces. If we suppose that paleolithic settlements gravitated to river channel, the second terrace, having large extension in the upper valley, may be considered as the most perspective area for discovering the paleolithic artefacts.
Special geomorphologic investigations were carried out at the southern slope of Stanovoi ridge. Slopes are shown to play the main role in the tructure and zoning of landforms; the stable slope associations of different dynamic types, an important role of tectonic tilts of land surface, self-development capability are the main features of the relief.
By system analysis of relief the regularities of its formation were determined; their correlation with gold deposits placing are discussed. The largest alluvial deposits gravitate to the regions of submaximal uplift and denudation cutoff, the largest bed-rock deposits - to areas of minimal ones.
The article deals with spatial and temporal variability of gully erosion within the region. On the basis of large-scale aerial data the density of gully network was determined and zoning of territory by this characteristic was fulfilled. Conjunctions of spatial differentiation of gully network with tilling degree, amount of woodland, relief, surface rocks were determined. The area dynamics of arable land and woodland during last four centuries was analyzed and these data were juxtaposed with gully network dynamics. Aerial data with 40 years lag show the distinct degressive trend of gully erosion in the second half of the XX century; the cause of this phenomenon is described.
The series of postglacial terraces surround the lake Imandra. Terraces of relative height -3 - - 11 m are built up with one stratum of limnoglacial deposits of Late Quaternary age. The sediment texture is characterised by cross-bedding, flexures and synclinal folds. Accumulation was influenced by tectonic movements, which were manifested in the inclination of terraces surface, and in splitting of initial surface in several levels. Terraces with relative height 0-3 m were built up with Holocene lacustrine deposits. Two stages of Holocene accumulation took place under the conditions of low tectonic activity. At one stage high socle terrace with thin stratum of lacustrine sediment was formed; at another - low accumulative terrace with horizontal lamination of deposits. Morphotectonics of Lake Imandra basin gives an evidence of direct reflection of neotectonic structure in the relief. Relative movements of small blocks come to first meters, while the whole amplitude of neotectonic movements in the basin reaches up to tens of meters.
Рецензии
Хроника
Потери науки
Памяти выдающегося азербайджанского геоморфолога Н.Ш. Ширинова (1922-2003)
ISSN 2949-1797 (Online)
