Bayesian Analysis of ²¹⁰Pb Dating

In studies of environmental change of the past few centuries, ²¹⁰Pb dating is often used to obtain chronologies for sedimentary sequences. One of the most commonly used approaches to estimate the age of material at different depths in a sequence is to assume a constant rate of supply (CRS) or influx of ‘unsupported’ ²¹⁰Pb from the atmosphere, together with a constant or varying amount of ‘supported’ ²¹⁰Pb. Current ²¹⁰Pb dating models do not use a proper statistical framework and provide poor estimates of the uncertainties. Here, we develop a new model for ²¹⁰Pb dating, where ages and values of supported and unsupported ²¹⁰Pb form part of the parameters. We apply our model to a case study from Canada as well as to some simulated examples. Our model can extend beyond the current CRS approach, deal with asymmetric errors and mix ²¹⁰Pb with other types of dating, thus obtaining more robust, realistic and statistically better defined age estimates.