In terms of neotectonics, the Timan Range and Kanin Peninsula represent a spacious mountainous structure 1150 km long and 80160 km wide extend ing in the northwesterly direction from Mount Poly udov ...Kamen to Cape Kanin Nos in the Kanin Penin sula. It consists of isolated en echelon arranged horst like uplifts with Upper Precambrian rocks cropping out in their arch parts. In the southwest the Timan Range borders the Pechora Plate that frames the Kare lian part of the East European Platform in the north east. The boundary between the Pechora Plate and Mezen megablock of the East European Platform cor responds to the West Timan deep seated fault.
The anthropogenic changes of permafrost are studied at the key sites in the European North, i.e., Koida Village (Mezen’ tundra), Nes’ Village (Kanin Peninsula), Shoina Village (Kanin Peninsula), ...Mezen’ Town, Vashutkiny Lakes (Bol’shezemel’skaya tundra), Amderma (Yugorskii Peninsula), and the northern part of Vaigach island. Geocryological characteristics of the sites are provided, and the main types of anthropogenic changes in permafrost conditions are described.
Lithogeochemical features of the Vendian mudstones and silty mudstones taken from Borehole Keltma 1 in the southern part of the Vychegda trough of the Mezen syneclise are discussed. It is shown that ...fine-grained clastic rocks of the Ust-Pinega, Krasavino, and Mezen formations have similar chemical compositions, suggesting their accumulation in sufficiently similar settings. The main part of the studied samples has K
2
O/Al
2
O
3
< 0.4. This fact, in combination with the absence of TM-FM and NPM-HM correlations, indicates a significant contribution of recycled aluminosiliciclastics in their composition. At the same time, the absence of correlation between CIA and indicator ratios of rock composition in the paleodrainage basins, such as Th/Cr and Th/Sc, indicates that CIA and some other lithochemical indicators appropriately reflect the paleoclimatic conditions in source areas surrounding a basin. The CIA value in most of the analyzed samples is no more than 70. Thus, the Keltma section is similar to Upper Vendian sequences of the Kvarkush-Kamennogorsk anticlinorium and the Shkapovo-Shikhany depression. It has been established that felsic and intermediate magmatic rocks coupled with a significant contribution of quartz-rich sediments served as the source of fine aluminosiliciclastics for the southern Vychegda trough during the Vendian. High Ce/Cr values in the mudstones and silty mudstones suggest that the geochemically primitive Archean protoliths were not involved in the washout. In the SiO
2
-K
2
O/Na
2
O diagram, the Vendian mudstones and silty mudstones are plotted in the field of sediments of active continental margins. Typical low values of Mo/Mn and some other redox indices in these rocks indicate that oxidizing environment predominated in bottom waters of the sedimentation basin during the entire Vendian. Analysis of variations of the lithochemical indicators upward the Vendian sedimentary successions in borehole Keltma 1 made it possible to divide the section into three sequences of different lithofacies and paleontological compositions.
Sediment successions from the Kanin Peninsula and Chyoshskaya Bay in northwestern Russia contain information on the marginal behaviour of all major ice sheets centred in Scandinavia, the Barents Sea ...and the Kara Sea during the Eemian‐Weichselian. Extensive luminescence dating of regional lithostratigraphical units, supported by biostratigraphical evidence, identifies four major ice advances at 100–90, 70–65, 55–45 and 20–18 kyr ago interbedded with lacustrine, glaciolacustrine and marine sediments. The widespread occurrence of marine tidal sediments deposited c. 65–60 kyr ago allows a stratigraphical division of the Middle Weichselian Barents Sea and Kara Sea ice sheets into two shelf‐based glaciations separated by almost complete deglaciation. The first ice dispersal centre was in the Barents Sea and thereafter in the Kara Sea. It is possible to extract both flow patterns from ice marginal landforms inside the southward termination. Accordingly, it is proposed that the Markhida line and its western continuation are asynchronous and originate from two separate glaciations before and after the marine transgression. The marine sedimentation occurred during a eustatic sea‐level rise of up to 20 m/1000 yr, i.e. the Mezen Transgression. We speculate that the rapid eustatic sea‐level rise triggered a collapse of the Barents Sea Ice Sheet at the MIS (Marine Isotope Stage) 4 to 3 transition. This is motivated by lack of an early marine highstand, the timing of events, and the marginal position of Arkhangelsk relative to open marine conditions.
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