Testing the MOD-AGE chronologies of lake sediment sequences dated by the 210Pb method

• We tested procedure for estimation one age–depth model from 14C and 210Pb ages.
• We compare results of 210Pb age depth model with historical data.
• We compare results of 210Pb age depth model with 14C age.

In this study, we tested the MOD-AGE procedure for non-parametric age–depth model computations for several lake sediment sequences dated by the 210Pb method. MOD-AGE uses the randomization method (a type of Monte Carlo simulation) for age–depth model construction and confidence band estimation and the LOESS (locally weighted scatterplot smoothing) method for fitting of the age–depth function. To validate the constructed age–depth models, we used (1) sediments of known age and (2) an independent radiometric dating method (radiocarbon dating). All tests confirmed that the MOD-AGE algorithm is a suitable tool for the calculation of age–depth models for lake sediment sequences. We also tested the MOD-AGE procedure for calculations based on the results of two different dating methods. The tests indicated that an age–depth model based on both data sets, i.e., probability distributions of 210Pb dates and radiocarbon dates, is more consistent than the age–depth models based only on one of the two data sets. The important advantage of MOD-AGE compared to other algorithms is that it models both age and depth value as well as their confidence bands while considering the uncertainties of these values.