Thawing of permafrost soils under the water intake facility (the Taas-Yurekh river, Yakutia, Russia)

Infrastructure development and oil field exploitation are facing great difficulties. This is caused by the engineering geological conditions changing and transformation of the upper part of the section due to the anthropogenic influence. The article contains the results of researching permafrost soils conditions in the bucket-type water intake facility foundation near the Taas-Yurekh River, Yakutia, Russia (the eastern block of Srednebotuobinskoye oil/gas-condensate field). As a result of the research area engineering geological conditions analysis, the geotechnical scheme was constructed, and on the base of it the soils thawing depth mathematical modelling due to the water heating influence was performed. The soils thawing depth calculation due to the heating of the water in the reservoir was performed with the TEMP/W software of GeoStudio, which is based on the finite element method. The forecast for the end of the facility lifetime was based on the temperature measurements in the reservoir and the soil surface. The calculations results show that the maximum thawing depth due to the water heating influence will be 36 meters with the lower border temperature of -1°C, and it decreases to 16 meters with -10°C lower border temperature