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The sulfur budget of the 2011 Grímsvötn eruption, Iceland
Author(s) -
Sigmarsson Olgeir,
Haddadi Baptiste,
Carn Simon,
Moune Séverine,
Gudnason Jónas,
Yang Kai,
Clarisse Lieven
Publication year - 2013
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1002/2013gl057760
Subject(s) - tephra , sulfur , plagioclase , sulfide , geology , magma , geochemistry , mineralogy , melt inclusions , basalt , sulfate , volcano , chemistry , quartz , paleontology , organic chemistry
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 SO 2 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.