ИСТИНА

Выявление закономерностей в литолого-геохимическом составе и строении пластовых льдов и вмещающих их отложений в западном секторе Российской Арктики для установления механизмов их формирования и реконструкции палеогеографических условий региона в конце позднего неоплейстоцена-голоцена

Massive ice beds (or tabular ground ice) are a unique phenomenon in the permafrost zone of the northern hemisphere. Massive ice beds are found mainly in the coastal arctic lowlands and lie mostly in Pleistocene (less often in Holocene) sediments. The main part of tabular ground ice is a relic of the Pleistocene period, and no modern in-situ formation of reservoir deposits has been found so far, except for the cases of burial of glacial ice and snowpacks, and the formation of ice on the seabed in places of gas emission [Melnikov, Spesivtsev, 1995; Badu, 2017, 2018, etc.]. Massive ice beds remain a stumbling block in paleogeographic reconstructions - the same deposits are considered by researchers to be buried glacial ice and indicate the presence of glaciation during the formation of frozen strata, or being initially intrasedimental ice, claiming the absence of large-scale glaciation in the Arctic coastal lowlands in the Middle and Late Pleistocene. Within the framework of the project, massive ice and host deposits will be considered both as a single system and as a result of the activity of separate processes - sedimentation and freezing. To reasonably establish the origin of massive ice, it is necessary to use a complex of modern analytical methods, including a joint study of the composition and microstructure of ice, inclusions in ice, host deposits and ice inclusions in them, the boundaries between ice and host deposits. For a key area in the north of the western sector of the Russian Arctic, a section of Pleistocene deposits with massive ice will be studied. In addition to a detailed field description of ice and host deposits, lithological, mineralogical, geochemical, macrofaunistic, geochronological methods will be used, the microstructure of ice will be studied in a cold laboratory. The application of an integrated approach based on a critical analysis of literature data, field materials and a block of laboratory methods will allow answering a number of existing questions about the nature of the development of massive ice beds in the Late Pleistocene and Holocene in the western sector of the Russian Arctic. As part of the project, it is planned to expand our understanding of the dynamics of the natural environment during the period of global climate change at the end of the Late Pleistocene and Holocene, as well as to correlate paleogeographic development for the northern and southern regions of Russia. The obtained data help to expand understanding of the development of natural systems adjacent to large marine basins. Data on the origin of massive ice will make it possible to clarify their spatial distribution, which is important for assessing the influence of massive ice on the development of permafrost processes under the conditions of both climatic changes in the Arctic and active economic development of the North.