Pleistocene periglacial features were studied in different areas of Hungary in comparison with Canadian recent cryogenic features. Pleistocene periglacial activity forms an important component of the landscape of the Carpathian Basin. There is a general consensus about the study and interpretation of cryogenic deformation structures (e.g., frost fissures, cryoturbations and involutions) being helpful in paleoenvironmental reconstructions. During the glacial periods of the Pleistocene, the Carpathian Basin was ice-free and subject to a cryogenic environment that produced various periglacial features. The reason for the cold climate during these glacial periods is the Basin's unique geographic setting. The Carpathians, which surrounds this large basin, creates an almost closed climatic situation, producing climatic conditions not found elsewhere in Europe. In effect, the climate in Hungary during the glacial periods of the Pleistocene was somewhat similar to the recent climate of the dry tundra regions of North Siberia. But according to other researchers, the Carpathian Basin was mostly devoid of permafrost during the Quaternary. Previous researches described so many relict forms in different geomorphic positions, but none of these have been revised according to the most recent research methods and permafrost nomenclature. Our review addresses past periglacial processes and their coupling to paleoclimate. Permafrost distribution in Canada shows a latitudinal zonation. The main annual temperature associated with these permafrost zones are 0° to -5.5°C (SPZ), -5.5° to -8.3°C (WPZ) and -8.3° to -17°C (CPZ). Sand wedges, frost cracks and ice wedges all develop in permafrost environments and are currently actively forming in the Continuous Permafrost Zone in Canada. The well-developed sand-wedge polygons, frost cracks, ice wedge casts and cryoturbated soils found in Hungary suggest that the Carpathian Basin was a permafrost-affected area during a cold, glacial part of the Weichselian (Late Pleniglacial, 22,000-18,000 years BP). At that time this area was most likely underlain by continuous permafrost.

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