Petrography and geochemical analysis of Arctic ikaite pseudomorphs from Utqiaġvik (Barrow), Alaska ...

• Main Authors: Schultz, Bo P., Huggett, Jennifer M., Kennedy, George L., Burger, Paul, Friis, Henrik, Jensen, Anne M., Kastrup, Marie, Bernasconi, Stefano M., Thibault, Nicolas, Ullmann, Clemens V., Vickers, Madeleine L.
• Format: Article in Journal/Newspaper
• Language: English
• Published: ETH Zurich 2023
• Subjects: Holocene; Coastal; Ikaite; Glendonite; Petrology; Isotopes; Arctic; Barrow; White Sea; Alaska
• Online Access: https://dx.doi.org/10.3929/ethz-b-000653800; http://hdl.handle.net/20.500.11850/653800

Ikaite and pseudomorphs thereafter (“glendonites”) are a potentially powerful tool for palaeoclimatic studies, as a low-temperature proxy. However, much uncertainty still surrounds the drivers of ikaite formation, in particular prerequisite thermal and chemical conditions. Furthermore, the ikaite to glendonite transformation is not fully understood, and it was unclear which calcite phases in glendonites were ikaite-derived and which were later diagenetic calcites. This leads to difficulties in choosing which phase to analyse in order to reconstruct the original ikaite growth environmental conditions. Petrographic examination of air-transformed ikaite from the Isatkoak Lagoon in Utqia?vik, Alaska, confirms that both ’Type I’ and ’Type II’ calcite phases seen in glendonites are directly derived from ikaite breakdown and not from secondary sources. Clumped isotope temperature reconstructions for transformed ikaites from Utqiaġvik, and comparison to Recent glendonites from the White Sea, Russia, confirm that ... : Norwegian Journal of Geology, 103 (1) ...