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Geomorfologiya i Paleogeografiya

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No 1 (2020)
3-21 488
Abstract
Despite the rapid development of computational technologies and methods and the increasing number of publications related to the geomorphometric analysis of terrain, no summaries in this branch of geomorphology were created in the last decade. In the “Russian-language” articles and books in geomorphometry this problem is especially relevant. Sometimes, geomorphometry has become regarded as a semi-marginal discipline which has no real importance for studying of landforms. The list of the main drags for thegeomorphometric analysis development is given in the article: geomorphological convergence and homology, not-interpretability of complex statistical models, slight representativeness of common metrics for automatictracing of geomorphological boundaries, and so on. The possible solutions of these problems on the way to the morpho-chrono-genetic mapping of landforms are scheduled. A short review is provided of clustering, classification, computer vision and pattern recognition, development and using of unusual geomorphometric variables. The article encourages geomorphologists to intensify their efforts (and to lead the researches if possible) in these four thematic directions to prevent the proceeding separation of traditional geomorphology and geomorphometry.

Ecological and Applied Geomorphology

22-33 237
Abstract
The study of the geomorphological characteristics of the Small Syrt relief using digital elevation models (DEM) and terrain models (TM)allowed to develop a regression model and to reveal the patterns of change in the slope heights in the catenas and to determine their statistical parameters. It was established that the topographic inhomogeneity in the Small Syrt has a significant effect on the manifestation of latitudinal zonality of soils. The dissection of the territory and the presence of river valleys contributes to the inhomogeneity of wetting, which leads to vertical differentiation of soils. The soil cover in the studied area belongs to the Zavolzhskaya dry steppe province represented by dark-chestnut, chestnut soils and in varying degrees, by the eroded types of meadow- and meadow-chestnut, estuary and floodplain soils, alkaline soils. Geoinformation researches of topography and soil contours showed a relationship of the change of soil types with terrain features. According to the results of field studies, morphological and physico-chemical characteristics were found and properties were presented on the profile of the main soil types. The conducted morphodynamic studies allowed to reveal the morphosculpture, spatial, linear and point landscape elements, characteristic changes in the spatial distribution of the soils related to the relief and provided new knowledge about the influence of the geomorphological features considered by the territory on their characteristics.

Scientific Research Methods

34-48 276
Abstract
Using repeated laser scanning, we analyzed the dynamics of exogenic geological processes (EGP) such as landslides, fluvial erosion, and thermokarst, for a pipeline section with a high concentration of these hazards. Air-borne imagery and field works were involved in detecting foci of the EPG. We compared laser scanning data from 2010 to 2011 and estimated topography changes resulted from the geological hazard activity in the pipeline vicinity. Variations of the topography at the landslide area were the greatest as well as those at the section with intense industrial activity. Fewer changes were found in the zones of removal and accumulation of material within the landslide area. We also detected a decrease of height marks in the areas of fluvial erosion and thermokarst sinks peripheries. In particular, the removal of 3827 m3 of material in the upper part of the test area resulted to noticeable lowering of the surface, and accumulation of 1890 m3 of material caused the rise of surface height.
49-52 253
Abstract
Since 1985, experiments have been conducted in the Kungur cave on the rate of dissolution of the host rocks and observations on the hydrogeochemical processes and morphometric parameters of the speleosystem. According to the long-term data, the rate of dissolution for the karst massif as a whole is about 20 m3 per year per 1 km2. In 2013, the dissolution rate of gypsum blocks embedded in lakes ranged from 0.026 to 0.039 g/year. The elevation marks of the observation stations equipped in the supporting columns of the longest cavern cave Dlinniy, have been constantly decreasing since the beginning of the measurements (2013). At the remaining stations, they are within the measurement error. In areas of development of sulphate karst, it is necessary to take into account the relatively high rate of dissolution process (several years or decades), commensurate with the service life of the engineering structures. The processes occurring on the surface and inside the karst massifs at present affect the course of the development of dangerous geological phenomena, including failures and floods.

Short communications

53-67 280
Abstract
The fragments of Dinskaya brachyanticline in the south-western coast of the Dinskoy Bay (Taman peninsula) were examined. Drevny-Evksin age (early Middle Neopleistocene) of two anticline flanks was refined. Paleomagnetic dating of south-east flank section was conducted for the first time; Early Pleistocene cervine horn and early Middle Neopleistocene teeth of small mammals were found in the section. Deformation of the Dinskaya anticline and other cases of folding in the Taman Peninsula allow to conclude on active tectonic movements in the Taman Peninsula in the late Neopleistocene.
68-80 293
Abstract

Comparison of the calculated profiles of dynamic equilibrium and the actual profiles of the underwater coastal slope showed that the majority of the shores of Lake Onega are characterized by poor stability. The profiles of the underwater coastal slope were obtained as a result of field work, including depth measurements and analysis of particle size distribution of bottom sediments along the profile line. Dynamic equilibrium profiles were obtained using the Dean-Brown formula, taking into account the prevailing size of bottom sediments. Previously, 7 morphogenetic types of shores were identified along the Onega Lake shores: poorly altered, abrasive, erosional-aggrading, aggrading, deltaic, lagoonal and technogenic. For various reasons, slightly modified and accumulative types can be considered relatively stable, but their stability is noticeably reduced due to an increase in the water level of the lake, which was about 0.5 m in the 20th century. Erosional coasts are the least stable. Weakly altered shores are common in the Northern Prionezhye, aggrading shores are found in the Southern and Eastern regions. Erosional shores predominate in the Western Prionezhye, and fragmentarily occur in the Eastern one. Instability and active dynamic processes characteristic of a significant part of the shore, cause long-term risks for their economical, in particular, recreational use.

Studies of the degree of coastal stability depending on their type by comparing the actual measured profiles of the underwater coastal slope with the constructed profiles of dynamic equilibrium are relevant for all the shores of seas and large inland waters, especially those that are intensively used by humans. This method of research allows us to identify sections of the shore with the least long-term risks for infrastructure facilities.

81-95 259
Abstract
On the basis of landform analysis of the Aldegonda Glacier proglacial zone, geomorphological indicators of its surge behavior in the Little Ice Age were proposed based on the features and rates of ice propagation and degradation during the phases of advance and retreat. These features were reconstructed from the configuration and location of lateral and terminal moraines (submarine and terrestrial) and according to historical data. Two different age generations of the left lateral moraine ridges were distinguished. The young lateral moraine dated to the Little Ice Age is oriented parallel to the axis of the glacier movement, and the ancient one (older than 12 ka) is at an angle to it. The difference in orientation is due to the different rate of the glacier movement that was slower before 12 ka ago and faster at 700–100 years ago. Different mechanisms were established for the formation of two terminal moraines: pushing (below sea level) and dumping (on land). The first one was interpreted as the result of rapid glacier advance, and the second one – as the result of the stabilization of the glacier front during the areal degradation of the terrestrial part of the glacier’s advanced tongue, followed by a rapid retreat of the front, as established by historical information. Landforms-indicators, such as fluted moraine and crevasse-fill ridges were suggested as the additional geomorphological features of surge behavior.
96-106 225
Abstract
For the first time for the Baikal rift zone, radiocarbon dates of humus horizons of buried Holocene soils in the profiles of debris flow fans were obtained on the right bank of the Irkut River along the Munch-Sardyk Ridge. Three stages of debris flow activity in Holocene have been identified: high (early Holocene – 10 thousand cal years ago), medium (3 thousand cal years ago – present) and low (between 10 and 3 thousand cal years ago). Apparently, the debris flow activity was determined by climatic conditions in the region and has been associated with the change of atmospheric precipitation. At the beginning of the Holocene precipitation exceeded their current level and one-time accumulation of debris flow deposits reached up to 5 m in thickness.

History of Science

107-114 470
Abstract
The name of Victor Pavlovich Filosofov is widely known to specialists in the field of geomorphology and cartography. His scientific and professional biography was formed in the regional community. He formed a scientific school, which academician I.P. Gerasimov called “Saratov geomorphological school”. He founded the laboratory of morphometric analysis at the Institute of Geology at Saratov University which served as the basis for the practice of students for almost 30 years, carried out applied studies and conducted theoretical synthesis. Two books by V.P. Filosofov devoted to morphometric analysis of relief for the search of tectonic structures are the best known in scientific community. Although his scientific interests were much broader and included issues of geomorphological mapping, plantation surfaces, genetic classification of plains, origin of the asymmetry of relief, etc.


ISSN 2949-1789 (Print)
ISSN 2949-1797 (Online)