REMOTE SENSING DATA OF THE PEATLANDS AS BASE OF DETECTING RISK SOURCE FOR THE LINEAR INFRASTRUCTURE BUILDING IN SOUTH PART OF CRYOLITHOZONE

ABSTRACT

The permafrost zone (cryolithozone) is undergoing now an intensive anthropogenic influence. The strongest influence of the linear structure could be heating of the upper part of the ground layer, thawing of ice inclusions, weakening of the soil and surface subsidence. The strongest risk for constructing engineering structures within the southern part of the cryolithozone results from peatlands because of peat soil with high ice content. The aim of this work is revealing main interpretation criteria of peatlands containing thawing, frozen, and ice-soil with the purpose of studying peatland dynamics along the linear structures in the southern part of cryolithozone. Using remote sensing data and basing on traditional methods of indicative interpretation, widely developed in bog science, it is possible to determine ice content reliably and, accordingly, the hazard. A joint study of remote sensing data and geological engineering survey was done for the study area. 128 peatland sites were detected on the base of suggested classification features along the pipeline route, which were ranged by their danger for the structure. The following types of peatlands were revealed: type 1 – peatlands with thawing thin peat; type 2 - peatlands with thawing thin peat surrounding by frozen soil; type 3 - peatlands with little and medium ice content in peat; 4 - peatlands with high ice content in peat. Accordingly, every type has got its rank of danger: type 1 – 0; type 2 – 1; type 3 – 2; type 4 – 3.

Keywords: peatlands, permafrost, icy ground, peat soils, remote sensing