This article explores alasses (thermokarst formations) in the Lena-Amga interfluve as a classic territory of permafrost landscapes. Definitions of alas (alas type of terrain) in geomorphology, permafrost and landscape studies are given. The morphometric characteristics of the sizes, features of the distribution and zoning of the alastness of the research area are given. In the course of a spatial analysis using geoinformation technologies, the features of the spatial location of the alas and the characteristic areas of their distribution were identified. Thus, following areas are considered: Leno-Amginsky alas erosion district, Leno-Tattinsky alas erosion district, Prialdansky alas erosion district, Priamginsky alas district, Pritattinsky alas district, Suola-Tamminsky alas district, Tyungyulyunsky alas district. An analysis of the distribution density of alasses revealed that, in general, on the territory of the Leno-Amga ice complex development, their density is quite uneven, in some areas alasses are very rare, and in some places they are very dense.

Aliona A. Shestakova
Candidate of Geographical Sciences
Senior Researcher of the Laboratory of Geographic Information Systems (GIS) and Permafrost Mapping
Melnikov Permafrost Institute of Siberian Branch of the Russian Academy of Sciences
36, Merzlotnaya St., Yakutsk, 677010, Russia
e-mail: aashest@mail.ru
ORCID ID: 0000-0002-0648-0362

Yaroslav I. Torgovkin
Candidate of Geographical Sciences
Head of the Laboratory of Geographic Information Systems (GIS) and Permafrost Mapping
Melnikov Permafrost Institute of Siberian Branch of the Russian Academy of Sciences
36, Merzlotnaya St., Yakutsk, 677010, Russia
e-mail: torgovkin@mpi.ysn.ru
ORCID ID: 0000-0002-7146-0798

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