Brief communication: Identification of 140 000-year-old blue ice in the Grove Mountains, East Antarctica, by krypton-81 dating

The presence of exceptionally old ice and relative ease of access make Antarctic blue-ice areas (BIAs) attractive paleoclimate archives. However, only a handful of BIAs, mostly situated in West Antarctica and along the Transantarctic Mountains, have been investigated for this purpose. Here, we present the age of surface ice from the Grove Mountains BIA in Princess Elizabeth Land, East Antarctica, determined by measuring inline-formula⁸¹Kr in the trapped air. Two samples yield an average age of inline-formula $M2inlinescrollmathml{\mathrm{normal\; 143}}_{-\mathrm{normal\; 29}}^{+\mathrm{normal\; 33}}$ 35pt17ptsvg-formulamathimgad30d90ec066907e65f6835051c718bd tc-18-1647-2024-ie00001.svg35pt17pttc-18-1647-2024-ie00001.png  kyr. Together with the reported terrestrial age of a chondrite, we conclude that the Grove Mountains BIA holds considerable potential for paleoclimate studies.