Radium and Thorium Isotopes GEOTRACES Arctic - HLY1502 (GN01) PI: Matthew Charette (WHOI) Co-PI: Willard Moore (University of South Carolina) Version History: 06 April 2020 (current) - version 3; re-formatted for GEOTRACES IDP compliance. 02 July 2019 - version 2; additional data columns reported; additional columns for units in dpm/L and mBq/kg. 31 October 2017 - version 1.