The study concentrates on the apparent contradiction in the occurrence of tundra peat deposits, namely that they are so widespread yet that much of the peat appears to be relict, on the basis of observations in the Amguema valley and in the Anadyr' Lowland in Chukotka. Results reveal that over wide areas the peat accumulations are experiencing denudation, i.e., that erosion of the peat is occurring faster than accumulation of organic material. This appears to be associated with greater surface runoff than during the peak period of peat accumulation. A related phenomenon, associated with the greater availability of moisture, is the recent invasion of many areas of peat formation bySphagnumparticularly in the Anadyr' Lowland. The study concludes with detailed analyses of the peculiarities of peat formation in polygonal tundra bogs and in string bogs.