A Correction for In-Situ 14C in Antarctic Ice with 14CO

Abstract

We use a dry extraction method to obtain trapped CO2 of shallow ice cores from a blue ice area of East Antarctica. In-situ-produced 14C extracted in 14CO2 and 14CO concentrations show a mean ratio of 3.4 +/0.4. Correction for insitu 14CO2 resulted in ice ages within 7-13 ka. The accumulation and ablation rates determined from the in-situ production of 7-20 cm yr-1 and 10-13 cm yr-1, respectively, agree with field measurements, and thus indicate close to total efficiency of extraction.