Modeling Atmospheric 14C Influences and 14C Ages of Marine Samples to 10,000 BC

Abstract

The detailed radiocarbon agevs.calibrated (cal) age studies of tree rings reported in this Calibration Issue provide a unique data set for precise14C age calibration of materials formed in isotopic equilibrium with atmospheric CO2. The situation is more complex for organisms formed in other reservoirs, such as lakes and oceans. Here the initial specific14C activity may differ from that of the contemporaneous atmosphere. The measured remaining14C activity of samples formed in such reservoirs not only reflects14C decay (related to sample age) but also the reservoir14C activity. As the measured sample14C activity figures into the calculation of a conventional14C age (Stuiver & Polach 1977), apparent14C age differences occur when contemporaneously grown samples of different reservoirs are dated.