Radiocarbon Measurements of Tree Rings from 14 ka Huon Pine

Abstract

We have measured the radiocarbon content of tree rings from a section of Huon pine retrieved from Tasmania. The sample was divided into 39 five-ring sub-samples covering a period of 194 years. Radiocarbon ages of each of these sub-samples was determined by making four measurements of each sub-sample at the Arizona AMS laboratory (Table 1). The resulting 1-sigma precisions are about 0.5%. A comparison of our data with the appropriate curve in INTCAL98 indicates that the calendar age of our sample is close to 14,000 cal BP. Using this age calibration, we have constructed a plot of Delta-14C versus assumed calendar age. This plot shows an essentially constant value over the youngest 125 rings of our sample. Over the oldest 75 yr of the sample, the Delta-14C curve exhibits three fluctuations, the largest of which is about 65 per mil. The time of the peaks in the Huon-pine 14C curve corresponds approximately with the European Bolling/Allerod climatic event. Work is in progress to extend the data 100 yr more toward older ages.