In this paper, we compare results of 14C and 210Pb dating of the peat profile Mauntschas-03, Switzerland. A previously published series of AMS 14C dates allowed us to build a precise age-depth model of that profile (Goslar et al. 2005), where the 14C-bomb peak (1964 AD) occurred at the depth of ca. 22 cm, and 65 cm corresponded to ca. 1810 AD. An alternative age-depth model was obtained using measurements of 210Pb over the profile. The 210Pb-based model suggests that between 25 and 60 cm the peat is 20-50 years younger than implied by the 14C data. Detailed consideration of the available data shows that the 210Pb-derived model is unlikely. The most probable reason for that is a limited retention capacity of Pb in the site. Using the 14C-based chronological model of the peat profile, we reconstruct past changes of Pb retention capacity in the profile for the last 150 years, and we discuss correlation of these changes with the history of evolution of the Mauntschas peatbog.
References: Goslar T., Van der Knaap W.O., Hicks S., Andric M., Czernik J., Goslar E., Rasanen S., Hyotyla H., 2005. Radiocarbon dating of modern peat profiles: pre- and post-bomb 14C variations in the construction of age-depth models. Radiocarbon, 47, 115-134.
See more of Poster Session I
See more of The 10th International Conference on Accelerator Mass Spectrometry (September 5-10, 2005)