Earth’s Cryosphere, 2022, Vol. XXVI, No. 2, p. 20-33.

FLOODPLAIN TALIK WIDTHS IN RELATION TO RIVER CATCHMENT AREAS AND CHANNEL TYPES

V.M. Mikhailov

North-Eastern Permafrost Research Station, Melnikov Permafrost Institute, Siberian Branch of the Russian Academy of Sciences, Portovaya str. 16, Magadan, 685000 Russia; vmmikhailov@gmail.com

Data on the width of floodplain taliks in river valleys of the mountainous areas in the northeast of Russia and adjacent areas of the Far East were gathered and organized. The investigated region extends from the Arctic coast to the southern limits of the continuous permafrost area. To assess talik widths, satellite images of high resolution from the Google Earth service and previously established indicative landscape features were applied. The catchment areas at downstream ends of the chosen 340 representative river sections varied from less than 10 to more than 200 000 km2; talik widths, from 41 to 4100 m. The rivers were subdivided into four channel types according to the degree of channel branching based on the previous studies confirming that the floodplain taliks were formed only by braided rivers on coarse-grained alluvium. The studied sites are generally evenly distributed both over the territory and according to the selected channel types. The changes in talik widths from marginal coastal to central continental river basins in relation to the channel type are discussed in this paper. The parameters of the empirical power-law dependence of the talik width on the catchment area of the river are calculated. The results obtained allow us to estimate the range of variation in the talik zone width on floodplain in dependence on the given river catchment area and determine the most probable minimum value of this parameter. In future, this approach in combination with field research will contribute to the improvement of remote sensing data interpretation.

Permafrost, floodplain taliks, talik width, river catchment areas, river channel types, interpretation of remote sensing data