²¹⁰pb as a chronometer and tracer, Burrinjuck Reservoir, Australia

Abstract

Abstract Cores taken at Burrinjuck Reservoir in southeastern New South Wales have been dated using the first appearance of 137 Cs, charcoal/bushfire correlations, and annual grass pollen peaks. None of the main 210 Pb dating models reproduced the ‘known’ chronology. Correlation analysis shows no significant relationship between original 210 Pb (unsupp.) concentration and grain‐size, sedimentation rate or loss on ignition. Differences in sediment source may explain the variations in 210 Pb. A simple provenance model has been used to interpret the ratio of original 210 Pb (unsupp.)/ 226 Ra as a tracer of topsoils and subsoils. High ratios in the reservoir sediments probably indicate eroded topsoils and low ratios eroded subsoils.