научный журнал по геологии Геоморфология ISSN: 0435-4281

2015

АРХИПОВА М.В., БЕРЕЗИН П.В., ВИКТОРОВ А.С., ЗВЕРЕВ А.В., КАПРАЛОВА В.Н., ОРЛОВ Т.В., ПАНЧЕНКО Е.Н., САДКОВ С.А., ТРАПЕЗНИКОВА О.Н. — 2015 г.

We analyzed different hypotheses of the thermokarst-lake plains development using mathematical modeling of their morphological pattern. Two different assumptions of thermokarst depressions growth were considered: 1) synchronous start, when period of emergence of initial lakes is relatively short compared with the period of their further development, and the number of depressions remains constant; 2) asynchronous start, when new thermokarst lakes appear permanently. Theoretical statements were empirically tested using real thermokarst lakes parameters at the 16 test sites in different permafrost regions. The analysis of the model and empirical testing of the results demonstrated prevailing lognormal distribution of thermokarst lakes areas and proved the synchronous lakes emergence on the assumption that the rate of the lakes growth is proportional to the density of thermal losses through the side surface of the lake.

СИДОРЧУК А.Ю. — 2015 г.

The further development of the N.I. Makkaveev’s theory of the unified erosion-deposition process is suggested. Manifestations of this process at different parts of the fluvial system (FS) were analyzed on the basis of the equation of sediment budget, which is universal and basic for all types of FS at different scales. The ratios of the values of the main terms in this equation: erosion, deposition and sediment flux from the catchment, are the explicit quantitative criteria for classification of the parts of FS and of their definition as erosional, dynamically stable or depositional, according to the sign of the sediment budget. It is proposed to define the overall FS type, from the head waters to a given cross-section, according to the delivery ratio.

ЛОПАТИН Д.В. — 2015 г.

The author argues that geomorphology should aim 1) to further development of the theory and methodology; 2) to investigate relief by geomorphological and general scientific methods, 3) to compile univocal geomorphologic map and to interpret geomorphological data; 4) to provide data bases for prospecting; 5) to develop engineer- geomorphologic assessments; 6) to investigate contemporary geomorphic processes; 7) to provide relief data bases for their use in GIS-technologies. The author suggests that all the readers of the journal “Geomorhpology” should focus their attention on the creation of a geomorphological code just to unify the conceptual language and some other theoretical elements of science.

АНИКИНА Н.В., ЛИХАЧЕВА Э.А., ШВАРЕВ С.В. — 2015 г.

Territorial resources of the New Moscow were analyzed in the aspect of geomorphological conditions. Analysis of the exogenous processes and anthropogenic transformation on the territory of the New Moscow shows that almost 1/5 of it involves certain difficulties for further development: the elimination of natural hazards and adaptation of the existing man-made infrastructure to new tasks are necessary. The main relief features, quantitative data on the exogenic processes, and the degree of anthropogenic transformation on the territory of New Moscow are described. The semi-quantitative models of the territory were created using the geographically-distributed database of geological-geomorphological conditions. The models include three aspects of the territory evaluation: the cultural-aesthetic, the geoecological and the geotechnical ones. In the conclusion the authors state the necessity to found the integrated assessment for rational use of the new territories on the cultural and aesthetic needs of the population. The partial models were integrated into a complex one based on a combination of attractiveness of the territory for life, as a priority factor, and on linked conditions of geoecological stability and geotechnical risk of the development. Recommendations with respect to the directions of territorial development, including the planned “growth points” of the New Moscow are given.

АФАНАСЬЕВ В.В. — 2015 г.

The presence of the frozen grounds on the coasts including the barrier lagoon ones, thermo-abrasion observed on some sites, the presence of shore ice and icings lasting up to the end of May, allow to consider the shores of the north-western and eastern Sakhalin as subarctic type. It was determined that during last 50 years more than 15 км 2 of accumulated plain was lost as a result of shore erosion only in the north and south-east of Sakhalin Island. The spatial structure of erosion has existed in its general outline since the 1930s. Since 1940 the extension of eroded shores has enlarged nearly two times. The spatial rhythms of erosion with wave length about 30 and 60 km determine the main regularities of shore erosion pattern. The formation of non-uniformity of beach structure and accordingly the irregular distribution of its wave- decreasing properties along the shore were considered. On the seashore of Sakhalin more than thirty sites were found, where quasi-rhythmic forms of shore relief were observed. But all the deformations of underwater relief were observed only in the frames of rated close depth. The special attention was devoted to the changes of wave-suppression characteristics of the beach during beach deposits freezing and under the open sea influence. The freezing of the 40-50 cm of the upper parts of shore profile and decrease of wave-suppression characteristics (mainly drainage and roughness), caused by this, occurred during this period before the formation of the shore ice and icings (1.5-2 months). According to the observations the height of swash zone increases by 30-45%. The calculations showed that the height of wave run-up for bank slope of storm bar may increase owing to freezing by 2-2.5 times. doi: 10.15356/0435-4281-2015-2-28-37

ЗЫКОВ Д.С. — 2015 г.

Horizontal component of neotectonic movements in platform conditions can be identified by comparing the morphostructural pattern of the region with the known structural models of horizontal deformations. Through the juncture of the Baltic shield and Barents plate, which is the part of the Western Arctic platform the two sutures pass: Karpinsky lineament - latitudinal zone of discontinuities, by which crystalline basement is dipping step by step seaward and thrust-shear structure Trollfjord-Rybachiy-Kanin. Characteristic features for this area are as follows: concentration of cracks, bearing tectonic mirrors and furrows slip, faults and near-fault deformations, manifested by the valleys and canyons, and the steps of relief, the formation of which cannot be explained by selective denudation of the substrate. The epicenters of earthquakes are numerous here. By the geological data the morphostructures were distinguished here with the indications of rotations of blocks, leading to the subsidences in the areas of stretching and shears along an echelon faults and also movements in mutually antithetic directions - right and left strike-slips of unknown age. Antithetic movements along the plate boundaries can be explained by the complex nature of the interaction of the East European platform with its frame.

МАМЕДОВ Г.М., НОВИКОВ И.С. — 2015 г.

The Dzungarian Plain and high mountains by its periphery were formed during Late Pliocene and Pleistocene on the territory of the former Cr-Pg peneplain. The Plain became the basin of accumulation for the products of mountain erosion. Three main steps of the relief were formed. The upper one includes the high and middle mountains, and intermountain depressions, occupying 146 000 km 2. The middle and lower steps form the Dzungarian Plain with the area of 223 500 km 2. Its marginal zone (the middle step) is represented by weakly changed peneplain (28% of the total area). The lower step in the central part consist of aeolean plains (21%), lacustrine plains (5%), allivial and alluvial-fan plains (21), aprons (10%), plains built on horizontal strata (11%), and advanced ridges (vorberges) (1%). Large contemporary and ancient river valleys occupy less than 3% of the territory.

КУЗНЕЦОВ Д.Д., ЛУДИКОВА А.В., САПЕЛКО Т.В., СУБЕТТО Д.А. — 2015 г.

Recent paleolimnological studies of the small lakes sediments in the northern Karelian Isthmus have demonstrated that the beginning of organic (gyttja) sedimentation in the Holocene was not simultaneous due to the differences in 1) the lake’s elevation, and 2) the proximity to the Lake Ladoga shoreline. Organic sedimentation in the lakes located at 30 m a.s.l. and higher started around 11000 cal. BP. No major changes in their hydrological conditions have been recorded hereafter. In the lowland lakes (11-20 m a.s.l.) located near the Lake Ladoga shoreline the beginning of organic sedimentation has been dated to 3000-4000 cal. BP. The underlying clayey gyttja contains lower amount of organic matter (10 %) with predominant diatom assemblages typical for Lake Ladoga. Therefore, the rapid increase in organic content in the lake sediments points at the isolation from Lake Ladoga, and enables to date the termination of the Ladoga transgression to 3000-4000 cal. BP. In the lakes situated at 11-14 m a.s.l. near the present watershed between the Gulf of Finland and Lake Ladoga, gyttja accumulation commenced at 3000-4000 cal. BP. Here the organic sediments overlie unsorted sand and silt that contain “large- lake” diatom taxa. Such sedimentary succession indicates that high-energy sedimentary environments (strait or river-like outlet from Lake Ladoga) persisted in the northern Karelian Isthmus until at least 4000 cal. BP when low-energy environments established resulted from Lake Ladoga regression. Hence, the small-lakes sedimentary records provide an independent evidence for the Lake Ladoga - Baltic Sea connection through the main Ladoga outlet in the north of the Karelian Isthmus in the mid-Holocene.

ЧИЧАГОВ В.П. — 2015 г.

КРИВЦОВ В.А., ПРАВКИН С.А. — 2015 г.

Large portion of steep bedrock slopes of the Oka river in the Ryazan region is occupied by extensive pediments 50-300 m width and 8-30° inclination. They are formed as a result of landslide occurring on the bedrock slopes composed of Neogene-Quaternary permeable sediments of 40 m depth underlain by confining layer of Jurassic clays. Groundwater discharge over the Jurassic clays provokes the insequent landslides, followed by the slope retreat into the interfluve areas, and by the formation of slightly dipping surface of the pediment. Denudation of valley pediments occurs mainly due to landslides moving over their surface. The width of valley pediments depends on the depth of Neogenc-Quaternary sediments and hypsometry of the Jurassic clays roof. The progressing erosive segmentation of the bedrock slopes prevents further sliding and widening of the pediments.

2015

2015

ГОЛОСОВ В.Н., ЖИДКИН А.П., ПЯТКОВА А.В., СВЕТЛИЧНЫЙ А.А. — 2015 г.

An assessment of the sediment spatial redistribution on two facing slopes of the site Gracheva hollow (Kursk region) was fulfilled. Soil-morphologic method, magnetic tracers, radiocesium dating, LISEM, and physical- statistical empirical model were used. By the complex of field methods related to different time intervals (150, 140 and 21 y.) regularities associated mainly with the influence of slope morphology on the sediment runoff and redeposition were obtained. On the dispersing convex slope all field methods showed wave-like alternation of the accumulation and wash-out, which manifests in and is augmented by the microrelief elements. According to the three field methods the value of the intra-slope accumulation ranges from 11% to 79% of the total dislodged material value; the mean value reaches 35% (with the use the erosion models calculations). On the straight convex slopes zones of alternation were not observed; accumulation close to slope bottom, revealed by soil-morphologic method and magnetic tracers, is connected with the changes of the low boundary of ploughing during agricultural exploitation. The calculated rates of sediment redeposition obtained with the erosion model LISEM helped to evaluate with sufficient validity the total wash out from the slope and to determine zones of sediment redestribution along the strike of the slope. The physical-statistical model also describes well the peculiarities of this process but gives less values of intra-slope accumulation than LISEM.

МАРАХТАНОВ В.П. — 2015 г.

The existing views on the physical conditions of cryogenic heave of grounds are discussed. It is shown that it is necessary to clearly distinguish between two types of ground systems: closed and open. For the closed systems the accepted models are physically correct. However, they are not suitable for the open systems. The positive land- forms of cryogenic heaving can rise by the Archimedean force due to the density difference between the thawed and frozen ground. Such a mechanism of swelling, considering the nature of the substrate in which it realizes, can be called lithostatic. The author worked out a theoretical framework including some mathematical assessments of the lithostatic mechanism. The appropriateness of the lithostatical concept is proved by the author's experiments, as well as by the actual data of other researchers. Lithostatic concept makes clear a number of peculiarities of cryogenic swellings, which previously had no strict physical explanation. Using the lithostatic concept for the explanation of various phenomena in the formation of the forms of cryogenic relief could be useful both in scientific, and in practical terms.

КОВАЛЕНКО М.А., САФЬЯНОВ ГА. — 2015 г.

Conditions and factors of a sediments granulometric differentiation on the beaches and intertidal zones of the test site of the White Sea beach are under consideration. Trends and results of transformation of sediments granulometric structure have been analyzed in the view of changes in the nature and direction of morpholithodynamic processes. Vectors of lithological changes and morphodynamic processes are closely associated. It is shown that the degree of transformation of sediments granulometric structure does not depend on the extent of morphometric changes and is more noticeable in dynamically stable areas of the coastal zone, where conditions for the influx of sediments of different origin and fractional composition exist. doi: 10.15356/0435-4281-2015-2-88-99

ЛУЗГИН Б.Н. — 2015 г.

The Sayan-Altai mountain systems occupy the area of “convergence” of three types of climate: extreme continental of the West Siberia, dry-steppe and semi-desert of Kazakhstan, and desert Mongolian (according to M.V. Tronov). The author has compiled morphoclimatic scheme of the Altai-Sayan mountain systems, with 6 morphoclimatic zones: humid, semi-humid, transitional humid-arid, semiarid, arid and ultra-arid ones. Digital mapping, carried out using satellite imagery, helped to standardize interpretive indicators of these zones and to unify the existing diverse and multi-scale materials on this area. An essencial condition for understanding the formation of climate in mountain areas is the consideration of the interaction of endogenous and exogenous forces in the processes of mountain building. The character of relief depends not only on the tectonic factors but on the exogenous processes as well - erosion and baro-thermal conditions (primarily) and processes determined by the dynamics of air flows.

НОВИКОВ И.С. — 2015 г.

In the result of geomorphological survey in the scale of 1: 50 000 performed in the central part of the Altai Mountains it was found that fragments of the Cretaceous-Paleogene peneplain preserved in the form of vast watershed areas in all the mountain ranges of the region, are actually a ladder of planation surfaces of different age raised at different heights during the neotectonic reactivation. A comparison of the explored area of the Kurai ridge with the tectonically stable Anabar-Udjinskoye interfluve (North of the Siberian platform), has shown the identity of geomorphological structure of the watershed areas and allowed us to extrapolate the datings obtained for the reference Siberian site on different fragments of the planation surfaces in the Altai. On this basios we conclude that on the watershed of the Kurai ridge within one neotectonic block greatest height occupy fragments of the most ancient Middle Cretaceous peneplain, the Late Cretaceous level is lower by 30-40 m, Paleogene - by 50-70 m, and Early Neogene - by 170-200 m. the Good state of preservation of the denudation levels ladder indicates the insignificance of watersheds denudation during Cenozoic. It also contradicts the model of slow dome-like deformation of the Altai in the Cenozoic with the formation of pediments in the periods of movements slowdown.

ЧЕРКАС О.В. — 2015 г.

Kuznetsk intermountain area originated in the Late Cenozoic at the place of the Kuznetsk Carbon basin and partly inherited its boundaries. The area is characterized by transit regime and practically lack sediments of the N-Q orogeny. Its step plain relief consist of the four planation surfaces of close heights with rare structure-denudation highlands - monadnocks - and netlike low-incised erosion valleys associated with neotectonic faults zones. Tectonic escarps of 200 m and higher are characteristic only for the boundaries with the Salair and Kuznetsk Alatau. Tectonic valleys and escarps are the natural boundaries between blocks with relatively homogenous characteristics what had made possible to use the scheme of the block divisibility as the base for compiling some applied maps.

ЛЕБЕДЕВА Е.В., МИХАЛЁВ Д.В., ШВАРЕВ С.В. — 2015 г.

Mapping and regional analysis of the “geomorphological tension” were made for the territory of the central fragment of the continental margin mountain system of the Andes (latitude between 5°S - 19°S). We determine the geomorphological tension as a susceptibility of the territory to the development of catastrophic processes. According to the regional level of generalization tension was evaluated in ordinal scores. Assessment was based on the analysis of seismicity, amount of precipitation, the depth of the relief dissection, and the spectrum of the dominant geomorphic processes. On the base of the results of mapping on the scale of 1:8 million it was determined that zone of maximum geomorphological tension is situated at the Western megaslope of the Peruvian Andes between latitudes 9 °S and 13°30'S and in the band width of 100 km from the Pacific coast. Its value here reaches 15-16 scores due to natural causes. The tension on the Eastern megaslope of the Andes ranges from 9 to 12 points, except for some areas where it rises to 13-14, and for the Altiplano where it decrease to 6-10 points. An important feature of the study area is the asymmetric distribution of geomorphological processes and the geomorphological tension, which differ significantly at the oceanic and the inland slopes of the mountain range. Comparison of data obtained for the two segments (NW and SE) of the circum pacific mountain belt allows to conclude about the existence of its geomorphological tension general regularities. The areas of potential catastrophic processes are located near the margin of the continent in either case.