The sulfur budget of the 2011 Grímsvötn eruption, Iceland

• Published in: Geophysical Research Letters
• Main Authors: Sigmarsson, Olgeir, Haddadi, Baptiste, Carn, Simon, Moune, Séverine, Gudnason, Jonas, Yang, Kai, Clarisse, Lieven
• Other Authors: Laboratoire Magmas et Volcans (LMV), Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Institute of Earth Sciences Reykjavik, University of Iceland Reykjavik, Department of Geological and Mining Engineering and Sciences, Michigan Technological University (MTU), Atmospheric Chemistry and Dynamics Laboratory Greenbelt, NASA Goddard Space Flight Center (GSFC), Spectroscopie de l'atmosphère, Service de Chimie Quantique et Photophysique, Université libre de Bruxelles (ULB)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2013
• Subjects: sulfur degassing; Grímsvötn volcano; satellite-based SO2 mass loading; sulfide globules; mineral melt inclusions; [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry; [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology; [SDE.MCG]Environmental Sciences/Global Changes; Iceland
• Online Access: https://hal.science/hal-00992831; https://hal.science/hal-00992831/document; https://hal.science/hal-00992831/file/Geophysical%20Research%20Letters%20-%202013%20-%20Sigmarsson%20-%20The%20sulfur%20budget%20of%20the%202011%20Gr%20msv%20tn%20eruption%20Iceland.pdf; https://doi.org/10.1002/2013GL057760

International audience Sulfur concentrations have been measured in 28 melt inclusions (MIs) in plagioclase, clinopyroxene, and olivine crystals extracted from tephra produced during the explosive eruption of Grímsvötn in May 2011. The results are compared to sulfur concentrations in the groundmass glass in order to estimate the mass of sulfur brought to surface during the eruption. Satellite measurements yield order of magnitude lower sulfur (~0.2 Tg) in the eruption plume than estimated from the difference between MI and the groundmass glass. This sulfur "deficit" is readily explained by sulfur adhering to tephra grains but principally by sulfide globules caused by basalt-sulfide melt exsolution before degassing. A mass balance calculation reveals that approximately ~0.8 Tg of SO2 is present as globules, representing ~50% of the total sulfur budget. Most of the sulfide globules likely reside at depth due to their elevated density, for potential later remobilization by new magma or hydrothermal circulation.