Radiocarbon Dates of Peat in Palsas of Northern Eurasia

¹⁴C dates of peat in palsas from different regions of Northern Eurasia are represented. The authors apply these dates to determine the age of active palsa growth during different periods of the Holocene in permafrost zone. Climatic conditions are important for permafrost and palsa formation. However, the local environment leads to varying palsa ages even within uniform climatic and geocryologic region. ¹⁴C dating has shown that the palsa age is almost independent of latitude and temperatures of the permafrost. The authors recognize at least four different ways of permafrost mound formation, depending on temperature and drainage conditions. This defines the ¹⁴C date distributions. The cyclic character of the palsa thickness is a result of their pulsating development: repeated freezing with heaving and repeated melting with subsidence. Data was compiled after Vasil'chuk and Lakhtina (1986) with additions from Belorusova and Ukraintseva (1980); O. S. Turkina, personal communication (1980); Starikov and Zhidovlenko (1981); Washburn and Stuiver (1985); F. Z. Glebov, personal communication (1990); Ospennikov (1991); Göttlich et al (1985)