In-situ analysis of lead and multiple sulfur isotopes in southern West Greenland peridotite sulfide grains reveal evidence for Eoarchean crustal recycling ...

• Main Authors: Lewis, Jonathan A., Schwarzenbach, Esther M., Liesegang, Moritz, van de Löcht, Julia, Schwarz, Alexander, Strauss, Harald, Münker, Carsten, Rosing, Minik T., Whitehouse, Martin J., Jeon, Heejin, Hoffmann, Elis
• Format: Text
• Language: English
• Published: Deutsche Geologische Gesellschaft - Geologische Vereinigung e.V. (DGGV) 2023
• Subjects: Greenland
• Online Access: https://dx.doi.org/10.48380/bv8w-t741; https://www.dggv.de/e-publikationen/in-situ-analysis-of-lead-and-multiple-sulfur-isotopes-in-southern-west-greenland-peridotite-sulfide-grains-reveal-evidence-for-eoarchean-crustal-recycling

Eoarchean peridotites from the area south of the Isua Supracrustal Belt (SOISB) in southern West Greenland have been found by previous studies to contain sulfur subject to mass independent fractionation (MIF-S), with positive Δ 33 S values indicating that these rocks have incorporated sedimentary sulfur recycled from Earth’s surface [1]. New in-situ secondary ion mass spectrometry measurements of sulfide grains found within these peridotites reveal that this MIF-S is hosted within the sulfide grains. Electron microprobe analyses of the sulfide grains reveal that they are predominantly composed of pentlandite and pyrrhotite, consistent with the typical sulfide mineralogy of mantle rocks. The peridotites displaying the least petrographic evidence for melt overprint (Group 1) were found to contain the highest average in-situ Δ 33 S values, +0.20±0.02‰, while those bearing more evidence for melt overprint (Group 2) had lower average in-situ Δ 33 S values, +0.09±0.03‰. These findings are in good agreement with ...