In particular, incompatibility of finite values for empirical data, which are constrained by detection limit and core length, with terms in the age calculation, which represent integrations to infinity, can generate erroneously old ages for deeper sections of cores.
We use high-resolution (70 × 70 μm/pixel) calibrated hyperspectral imaging of a varved lake sediment core from meromictic Lake Jaczno (north-east Poland), to quantitatively map the spatial distribution of Bacteriopheophytin a (Bphe a) at very high sub-varve (i.e. Bphe a is a bacterial pigment and stable degradation product of Bacteriochlorophyll a (Bchl a), which is produced by anoxygenic phototrophic bacteria (APBs) at the chemocline of meromictic lakes.²¹⁰Pb dating provides a valuable, widely used means of establishing recent chronologies for sediments and other accumulating natural deposits.The Constant Rate of Supply (CRS) model is the most versatile and widely used method for establishing ²¹⁰Pb chronologies but, when using this model, care must be taken to account for limitations imposed by sampling and analytical factors.CE 1920, the climatic influence generally decreased in the following decades as the lake remained persistently in a meromictic state due to eutrophication.
However, the climatic fingerprint remained detectable for very warm or cold summers.
We used three excess 210Pb-based (210Pbxs) sedimentation rate models (constant 210Pb flux and sedimentation, constant rate of supply of 210Pb and constant initial 210Pb concentration) to develop core chronologies and compared them to the chronology obtained from the 137Cs peak.