# Comparison of \({}^{210}\)Pb Age Models of Peat Cores Derived from the Arkhangelsk Region
###### Abstract  
Dating young peatlands using the \({}^{210}\)Pb dating procedure is a challenging task. The traditional \({}^{210}\)Pb age models assume an exponential decline in radioactivity in line with depth in the peat profile. Lead exhibits considerable migratory capacity in Arctic peatlands; hence, to perform precise peat dating, existing models should be enhanced to remove the effects of migration. Independent isotope chronometers, such as \({}^{137}\)Cs, can verify this. The Monte Carlo method and IP-CRS were utilised, together with several CA, CF/CS, PF, and CF models, to analyse the peat core samples acquired in the Arkhangelsk region. Data analysis revealed that the height partitioning of \({}^{137}\)Cs and \({}^{210}\)Pb is associated with physical characteristics, like the peat ash and the bulk density of the bog. Comparison between the natural activity of \({}^{210}\)Pb in the peat and the radioactivity of \({}^{137}\)Cs measured at depths of 19-21 cm in relation to the global fallout in 1963 indicated that the CF/CS, CF, and IP-CRS models (1965, 1962 and 1964, respectively) gave the closest age to the reference point given. IP-CRS was found to be the preferred model of these three options, as it gave a rather closer correlation with the \({}^{137}\)Cs activity specific to the reference layer, allowing the error. The core dating of \({}^{210}\)Pb showed an age of 1963 for a depth of 17-19 cm, which was in agreement with the reference horizon \({}^{137}\)Cs and ash content, thus validating the accuracy and sufficiency of the selected model turf profile chronology. The maximum content of man-made radioisotopes in the peatlands corresponded to the formulation of the Partial Test Ban Treaty of 1963. The rates of accumulation of peat and atmospheric flux of \({}^{210}\)Pb are in good agreement with the values available for the bogs of Northern Europe and those previously estimated by the authors in the subarctic region of European Russia. Although the problems of the complex migration-related distribution of \({}^{210}\)Pb in the peat layer were considered, the dating methods used were effective in our study and can be adapted in following studies to perform the age determination of different peat deposits. p 2023 13 10486 15 August 2023 15 September 2023 20 September 2023 2023 2023 2023 2023 2023 2023 2023 2023 2023  
a component of the \({}^{238}\)U chain, is commonly used as an autonomous geochronometer to perform \({}^{137}\)Cs dating in studies of peat deposit accumulation to verify man-made radionuclide data [6]. It is important to note that dating performed via this method is a challenging problem due to the planned migration capacity of Pb in modern peatlands, as standard dating models assume an exponential decline in \({}^{210}\)Pb activity with the depth of the core, giving a rather precise and complete time line for the peat. [7]. Accurate dating requires the proper selection of dating models, with refinement and subsequent validation using independent radioisotopes, e.g., \({}^{137}\)Cs. The rationale is that the maximum levels of man-made radionuclides in natural sediments correspond to specific radioactivity episodes in the past, especially the signing of the 1963 Partial Test Ban Treaty, which provides an appropriate time point for this study. In the present study, the authors used dating models, such as CA (constant activity model), CF/CS (constant sedimentation model), PF (periodic flow model), and CF (constant flow model) via the Monte Carlo simulation method and IP-CRS (initial penetration-constant rate of supply model). Their features were briefly outlined to allow researchers to choose the most correct model. Since the start of the nuclear century on Earth, bogs have begun to contain man-made radioactivity and other isotopes released into the atmosphere via nuclear tests and radiation emergencies [8]. Studying radionuclides from atmospheric fallout in peats is an essential way of studying peat chronology, peat deposit formation, the productivity of peatlands over time, etc. [9].