TESTING THE USE OF δ~2H VALUES FOR RESERVOIR CORRECTIONS IN RADIOCARBON DATING HUMAN BONE

摘要

Consumption of marine protein in humans and animals can result in an apparent older radiocarbon (~(14)C) age due to reservoir offsets. In order to correct for this, an estimate of the marine protein intake should be used to correct the ~(14)C age for reservoir offsets, which is ordinarily done using δ~(13)C or δ~(15) N values. However, these two isotopic proxies can be influenced by a number of factors which can hamper estimation of the correct marine protein intake. A small dataset of 12 samples from the Limfjord, Denmark, ranging in age from Mesolithic to Viking Age, was used to test the use of δ~2~H values to quantify marine protein intake and determine the reservoir corrections. Each of the three stable isotopic values (δ~2H, δ~(13)C, δ~(15)N) was used to estimate the percent marine protein intake, which produced three different calibrated~(14)C ages. The calculated percent marine protein intake differed between the use of the stable isotopic ratios with a maximum difference of 42.1% between the use of δ~(15)N and δ~(13)C, 23.8% between δ~2H and δ~(13)C, and 46.2% between δ~2H and δ~(15)N. In some cases the calculated percent marine protein intake changed the sample's archaeological period, although there was generally still overlap in the archaeological periods for samples used in this study.