Abstract: The object of this work is the polar landscapes of Eastern Chukotka. The research task is to determine the nature and specificity of geological and geomorphological structure of the territory in typical and anomalous environments of cryolithomorphogenesis. The goal consists in the theoretical and practical studies of sustainability and plasticity of the polar geosystems on the background of climatic changes, amid the conflicting interactions between continentality and oceanicity. Special attention is given to the detailed analysis of morpholythogenic effects of the typical and anomalous (extreme – critical and crisis, as well as disastrous) processes and factors. The main conclusion lies in the following: in the course of development of the northern territories and increased interference in their natural environment, all permafrost processes are activated, with the leading role of thermokarst. Special contribution into the study is defined by the fact that, in the context of the upcoming continentalization of climate and assumed conservation the territory in Eastern Chukotka, the traceable natural risks are reducing, and the geosystems, most commonly, retain their initial sustainability. The exogenous crisis situations and disasters are forecasted, which allows making adjustments to the practice of optimal natural resource management. The scientific novelty lies in tracing the sustainable development of the territory, considering not only the compound, but also thorough complexation of the living and fossil.

Keywords: anthropogenic, natural risks, sustainability, zoning, structure, belt, polar landscapes, geosystem,, Arctic, Eastern Chukotka

Abstract: This article presents the results of lineament and structural-geomorphological analysis of the part of Karelian coast of the White Sea. The coasts of the Kandalaksha Gulf have significantly uplifted in the Neotectonic time; this is the territory of most intense post-glacial rise within the Baltic shield. A combination of glacio-isostatic compensational uplift after deglaciation, tectonic movements and eustatic sea level uplift has formed the modern image of coastland. The goal of this work lies in determining the existence of differentiated movements of crustal blocks on a scale of smaller blocks, which size does not exceed several tens of kilometers. The authors conducted the lineament and structural-geomorphologic analysis based on the field data, literary material and remotely sensed data. The data on the relative sea level changes in the regions, acquired mostly via the method of isolated basins, was imposed upon the obtained maps demonstrating lineaments and blocks. The authors assess the pace of the relative uplift of the blocks, their spatial and temporal change. The presence of graded block movements with differences in amplitudes reaching 20 m. Their character of such graded movements overall corresponds with distribution common to glacio-isostatic uplift, at maximum speed, gravitating towards the center of glaciation; however, the position of the most rapidly uplifting Rugozerko-Kuzakotskiy block can be explained only by the tectonic movements. It is revealed that a significant role in development of the structural plan of the territory was played by the reactivated Onega-Kandalaksha paleorift. It is demonstrated that its northwestern branch has different pressure that the central, which confirms the fact that this part of graben originated at Neotectonic stage.

Keywords: coastal geomorphology, Karelian coast, crustal movements, White Sea, lineament analysis, sea level, Neotectonics, structural-geomorphologic analysis, block movements, jointing

Abstract: The subject of the study is the cyclicality of the yedoma strata in the Mayn River valley of Southern Chukotka. The author explores the Late Pleistocene syngenetic strata containing syngenetic ice wedges in the Mayn River valley of Southern Chukotka: lacustrine and lacustrine-alluvial sediments in the Ledovy exposure outcrop, and lacustrine-alluvial sediments of the Ust’-Algan exposure. These strata are located close to each other, and formed with the diverse in lithological composition and facies sendiments: from coarse sand with pebble of river facies to silty facies, permeated with thick ice wedges of different configurations. The main research method is the field study of cryolithological structure of the natural exposures. The author also examines the radiocarbon age of the strata of the wedges, the oxygen-isotope and hydrochemical composition of ice wedges. The following conclusions were made:1. The hierarchy of the main types of cyclicity, observed in the studied syncryogenic strata is clarified;2. The duration of micro-, meso- and macro-cycles in formation of the yedoma strata of the Main River valley is determined- cyclite polygonal ice wedges in the section of lacustrine strata of the Ledovy exposure- heterocyclic polygonal ice wedges of in the section of lacustrine-alluvial yedoma of Ledovy exposure- heterocyclitic polygonal ice wedges in the  section of Ust’-Algan exposure.

Keywords: cyclicality, oxygen isotopes, radiocarbon, yedoma, ice wedge, permafrost, Mayn River, Late Pleistocene, syngenetic, palaeogeocryology

Abstract: The study is devoted to the late Pleistocene-Holocene paleogeography of the central part of the Gydan Peninsula in the area of the Parisento. The work covers the results of field studies in the area of Lake Parisento and in the middle reaches of the Gydansky Yuribey. The study is based on field data, radiocarbon and OSL - dating and correlation with data from previous studies. It was established that in the lower part of the sections, Kazan-Early-Zyrian (MIS 5-4) dark gray loams and sandy loams outcrop. Above lie the Kargin-Sartan (MIS 3-2) lacustrine, or lacustrine-alluvial gray horizontally and cross-stratified sands that make up the surface at elevations of 20-30 m in the vicinity of Lake Parisento. Kargin-Sartan (MIS 3-2) alluvial light-gray fine-grained sands with wave lamination interbedded with dark-gray sandy loams and loams were found on the right bank of Yuribey River in the southeast of the area. Above are the Sartan (MIS 2) and Holocene gray cover sandy loams and loams. They lie at the top of the sections at elevations of 40-50 m. Holocene peats are encountered on top of the sections at various geomorphological levels.

Keywords: OSL, Western Siberia, Quaternary geology, latest deposits, palaeogeography, Parisento, Gydan, Quaternary period, radiocarbon, alluvial sediments

Abstract: The object of this research is the yedomas in Alaska and Klondike with the well-defined cyclic qualities. The author examines the mesocyclic polygonal-lode complex McLeod Point, mesocyclic polygonal-lode complex  on the Itkillik River, mesocyclic polygonal-lode complex in Chatanika, mesocyclic polygonal-lode complex  in the Last Chance Creek valley, mesocyclic polygonal-lode complex in the Fox permafrost tunnel, mesocyclites in the Seward Peninsula, Colville River valley, the northern slope of Alaska, and Klondike near Dawson City. The main research method contains the analysis of cryolithological structure, radiocarbon dating, oxygen-isotope and hydrogen-isotope data. The main result of the conducted research lies in identification of mesocyclites in the Alaska and Klondike yedomas, such as: a) there are three vertical growth mesocyclitic stages in the MacLeod Point yedoma; b) four vertical growth mesocyclitic stages are common in the Chatanika yedoma; c) at least four vertical growth mesocyclitic stages are identified in the Itkillik yedoma; d) at least four vertical growth mesocyclitic stages are revealed in the Fox permafrost yedoma; e) at least four vertical growth mesocyclitic stages are tiers are distinguished in the Last Chance Creek valley; f) large, two or more layered syngenetic lodes are detected in the Seward Peninsula, Colville River valley , and the northern slope of Alaska yedomas – two-layered lodes; g) Klondike yedoma, near the Dawson City, is characterized with powerful two-three layered syngenetic lodes.

Keywords: deuterium, oxygen isotopes, radiocarbon, yedoma, ice wedge, permafrost, Late Pleistocene, syngenetic, cyclicality, Alaska and Yukon

Abstract: The subject of this research is the stratigraphy and paleography of the Middle Neo-Pleistocene of the north of Western Siberia. The authors examine the sediments of the Middle Neo-Pleistocene of Yenisei North, including Taz and Shirta horizons, correlated with marine isotope stages 6 and 7. The affiliation of the explored sections to the upper link of the Middle Neo-Pleistocene was substantiated by the chronometric studies, as well as sectoral position, palynological and microfaunistic data. Special attention is given to the genetic interpretation of sediments based on the results of the author’s personal laboratory and analytical data and published records. The goal of this work lies examination of the Middle Neo-Pleistocene sediments of the Yenisei North, as well as determination of their age and genesis on the basis of comprehensive analysis of the key sections. The authors applied lithological, microfaunistic, and palynological methods of research; as well as conducted age dating via the method of infrared-stimulated luminescence (IR-OSL). The obtained dating ranging between 166 and 217 thousand years ago on four key sections, including the stratotype of the Sanchugovskaya suite. Among the sediments of the Middle Neo-Pleistocene, there are varieties from pure sands to clayey silts and unsorted hybrid rocks. The results of lithological and paleontological analyzes testify to the marine origin of sediments from the majority of the sections explored. Such sediments contain the marine mollusks and foraminifera in situ. The results can be used for revising the paleogeography of Western Siberia in the Middle Neo-Pleistocene.

Keywords: genetic interpretation, geochronology, Sanchugov suite, Shirtin horizon, Taz horizon, Western Siberia, Middle Neo-Pleistocene, diamict rocks, quaternary sediments, key sections