Suchergebnisse

The scale of anthropogenic terrain transformation within the Norilsk industrial region was quantified and a classification of its consequences has been elaborated. The work is based on the results of 2021 expeditionary geomorphologic studies, interpretation and analysis of remote sensing materials and digital elevation models. It has been established that the total area of direct terrain transformation during the territory development was about 122,4 km2, and that of indirect transformation - 23,6 km2. The volume of anthropogenic landforms is at least 1,8 billion m3; accumulative forms account for 93% of the area and 72,6% of the volume of direct landform transformations. The types of anthropogenic landforms were identified, it was found that the largest area is occupied by embankments for industrial development and tailings, and the largest volume is characteristic of slope dumps. Indirect terrain transformation is mainly activation of gravitational processes, linear erosion, suffusion, thermokarst, heaving and deflation. The mass displacement of slope dumps by landslides or stone glaciers are the most dangerous for infrastructure facilities. Separate areas of indirect transformations are mainly limited to the lacustrine-alluvial lowlands and the bottoms of river valleys. Among them, the largest area (up to 20 km2) is occupied by segments of river valleys affected by spills of oil products and tailings. It has been established that the accumulation of pollutants in river valleys of the Norilsk industrial region occurs within the internal deltas and ice glades where the longitudinal slope decreases. Three stages of anthropogenic development of the territory are distinguished (I - 1920-1953; II - 1953-1986; III - 1986-2021); the most significant increment in the area of anthropogenic terrain occurred from 1953 to 1986. The average rate of anthropogenic terrain area increment over the past 36 years amounted to 0,81 km2/year. The highest rates of area growth are characteristic of the Kayerkan and Talnakh regions, which is associated with ongoing mining.

The article presents the results of an extensive study of the bottom topography of the Ob River Gulf in the Kara Sea, which is a follow-up to the long-term studies of the authors. It refines the existing ideas and aims at solving a fundamental problem of reconstructing the conditions for the formation of bottom topography in the shallow bays of the Kara Sea in the Late Pleistocene and Holocene. The work aims to create a regional characteristic of the geomorphologic structure of the Ob River Gulf bottom. The initial data on the bottom topography were taken from marine navigational maps and sounding boards at a scale of 1:50 000 - 1:100 000. We processed and interpreted the collected cartographic material to create a detailed DEM of the bottom and a bathymetric map at a scale of 1:200 000 with an isobaths interval of 1 m. In addition to bathymetric data, the compilation of a geomorphologic map engaged a large amount of literature and stock materials on geomorphology, geology, and geocryology of the region. The original morphogenetic legend was elaborated with due account of current ideas regarding the conditions for the formation of periglacial plains relief at the regressive stage of the Kara Sea shelf evolution. It was found that the relict fluvial relief prevails within the gulf and was partly modified by subaqueous processes during post-LGM transgression and the current epoch. We have indicated the most critical features of the structure and pattern of the flooded pravalley of the Ob River, as well as the total ancient erosion network. The selected individual forms and relief elements take into account the scale of objects and the degree of their generalization on the map and give an idea of the development of relief-forming processes both at the subaerial stage and under subaqueous conditions, including specific features of modern dynamics of the coastal and bottom relief.