Recent evolution of the overall radioactive levels in the ice of Livingston Island (Antarctica)

A study was carried out of the physico-chemical characteristics of the different layers of ice to a depth of 8.32 m in the Hurd glacier on Livingston Island in the South Shetland archipelago (Antarctica). No dependence on depth was observed for the pH, dry residue, or the concentrations of Ca2+, Mg2+, and K+ ions. The only dependence observed was a systematic increase in density from 0.5 to 0.85 g cm−3 due to the greater compaction of the deeper layers. The mean annual mass balance was determined by two methods: localization of the ashes emitted by a volcano on Deception Island and by means of a 210Pb dating method. The result in both cases was a value of 0.24 kg m−2 yr−1, which allowed us to date different layers of ice sampled. The mean annual 210Pb fallout was determined to be 1.9 Bq m−2 yr−1. While no systematic variations in total β activity were observed with depth, they were observed for total α and residual β activities in the said ice layers.