Geocryological conditions of the Tokarikan and Guvilgra grabens (South Yakutia)

Abstract

This article presents the results of geocryological studies of the Tokarikan and Guvilgra grabens of the Aldan Shield. Expedition research on the hard-to-rich region since 1996 has allowed us to determine the temperature regime, thickness, and nature of permafrost rock distribution and characterize its geocryological conditions for the first time. We have established that the lowest temperatures (up to –3.4 °С) are characteristic of peatmoss bog landscapes, whereas the highest (–0.5 °С) are for well-drained and watershed areas. The results of the measurements in deep wells, information on the process of drilling deep exploration wells, and the analysis of data on the thermophysical properties of rocks allowed us to estimate a permafrost thickness capacity that varied in the range of 40–260 m. The presented schematic permafrost and geological cross-sections and geocryological condition maps can be used to plan the industrial development of the territory.