Mineral Transformations in Permafrost‐Affected Soils, North Kolyma Lowland, Russia

• Published in: Soil Science Society of America Journal
• Main Authors: Alekseev, A., Alekseeva, T., Ostroumov, V., Siegert, C., Gradusov, B.
• Other Authors: Independent States of the Former Soviet Union
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2003
• Subjects: Soil Science; Kolyma; permafrost; Siberia
• Online Access: http://dx.doi.org/10.2136/sssaj2003.5960; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.2136%2Fsssaj2003.5960; http://onlinelibrary.wiley.com/wol1/doi/10.2136/sssaj2003.5960/fullpdf

Soils in permafrost sediments were studied on the Kolyma Lowland, North‐East Siberia. Mineral transformations were studied by comparing samples from different geochemical positions relative to the permafrost table. The profiles studied are developed from Yedoma deposits (mid to late Pleistocene). Mineralogical composition of study soils is controlled by the illite‐chlorite mineralogy of the parent Yedoma deposits, climatic conditions (extremely cold and dry) and the effect of permafrost. Degradation of illite, weathering of Fe‐containing minerals (chlorite) with further Fe migration within the active layer and its crystallization at the cryogenic barrier in the form of lepidocrocite are the main processes of mineral transformations in the Kriozems studied. The highest concentration of lepidocrocite is associated with the boundary of permanently frozen ground. Geochemical processes are strongly influenced by the permafrost table. The boundary between the seasonally thawing soil and the permanently frozen ground is an important geochemical barrier.