Brief communication: Alternation of thaw zones and deep permafrost in the cold climate conditions of the East Siberian Mountains, Suntar-Khayata Range

• Published in: The Cryosphere
• Main Authors: R. Sysolyatin, S. Serikov, A. Kirillin, A. Litovko, M. Sivtsev
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2023
• Subjects: Environmental sciences; GE1-350; Geology; QE1-996.5; Talik; Suntar; permafrost; The Cryosphere
• Online Access: https://doi.org/10.5194/tc-17-4601-2023; https://doaj.org/article/d70c9ec418644133a8a6ca2a9bbc99ce

The Suntar-Khayata Range includes numerous natural phenomena interacting with or depending on permafrost conditions. Here, we examine some patterns of deep permafrost and talik zones on adjacent sites. A 210 m deep borehole in siltstone bedrock was equipped for the temperature monitoring of the topmost 15 m and measurements of a deep permafrost temperature profile in July 2010. The temperature curvature in the upper part has a bend, which is consistent with the upper portion justified by climate warming, and shows a steady-state linear geothermal profile below 85 m depth with a high geothermal heat flux. A shallow borehole situated at the river floodplain was used to investigate the thaw zone's temperature regime. The temperatures down to 6.7 m deep have been monitored at 5 min intervals during heavy rainfall, and the temperature readings have behaved quite peculiarly. The thickness of the seasonal freezing layer reaches 5.7 m; moreover the ground temperature increases to 6 ∘ C at 6.7 m depth by groundwater heat transfer. This study provides some new insights into the permafrost condition at one of the coldest places in the Northern Hemisphere.