Comparison of 210Pb dating models as applied to peat deposits of the European subarctic of Russia (evidence from the Arkhangelsk region)

The dating of young peatlands with 210Pb method is a difficult task. Standard 210Pb dating models require an exponential decrease in activity down the peat profile. In Arctic peatlands, we note a significant migratory capacity of lead, therefore, for accurate dating of peat, it is necessary to improve the existing dating models to eliminate the effect of migration and their verification using independent isotope chronometers, for example, 137Cs. We applied several models CA, CFCS, PF, CF together with the Monte Carlo method for peat core samples taken within the European Subarctic of Russia (Arkhangelsk region). Comparison with the specific activities of 137Cs, determined at a depth of 19-21 cm, associated with the global fallout in 1963, showed that the closest age to the specified reference point is given by the CFCS and CF models (1965 and 1962, respectively). Among these two options, CF using the Monte Carlo method turned out to be preferable, since it provided, taking into account the error, a slightly better agreement with the specific activities of 137Cs in the reference horizon. Despite the difficulties associated with the complex distribution of 210Pb over the peat section due to migration, the dating methods used were successful and, in the future, can be applied to dating other peat deposits.