Radiocarbon Variations from Tasmanian Conifers - 1st Results from Late Pleistocene and Holocene Logs

Dendrochronological studies have begun on two conifer species in the Stanley River area of western Tasmania. The chronology extends to 273 BC for Huon pine (Lagarostrobos franklinii) and to AD 1450 for celery-top pine (Phyllocladus aspleniifolius). Apart from living or recently felled trees, sections have been taken from 58 logs preserved in floodplain sediments. Two of these logs have late Pleistocene ages, centered around 13.0 and 12.7 k C-14 yr BP. Four logs are between 8 and 9 ka BP, and one is centered at 7.3 ka BP. The remaining logs have various ages between 6.2 ka BP and the present. C-14 measurements have been performed on decadal samples from the two late Pleistocene logs, providing short (260-yr) records of atmospheric C-14 variations when plotted against individual ring numbers. Decadal measurements on the 7300-yr-old log have been wiggle-matched with C-14 calibration curves from German oak and bristlecone pine. Measurements for the period, AD 1600-1800, show good agreement with northern hemisphere results, and a nearly zero offset between the hemispheres.