TY - JOUR

T1 - Sulphur solubility in andesitic to basaltic melts

T2 - Implications for Hekla volcano

AU - Moune, Séverine

AU - Holtz, François

AU - Botcharnikov, Roman E.

N1 - Funding Information: Acknowledgments We acknowledge thoughtful and constructive comments on the manuscript by two reviewers: Paul Wallace and Jim Webster. We are grateful to Olgeir Sigmarsson for supplying samples and for discussions and Jean-Luc Devidal for supplying ALV981R23. Otto Diedrich is greatly acknowledged for the preparation of samples for analysis. Jürgen Koepke, Stephan Schönborn and Sara Fanara are acknowledged for their help with the analytical work. Séverine has really appreciated to work with Sandrin Feig and Oliver Beermann during her first steps in petrological experiments. Don Baker and Paul Wallace are really acknowledged for our fruitful discussions. For this project, Séverine was funded by the Humboldt foundation. Copyright: Copyright 2009 Elsevier B.V., All rights reserved.

PY - 2008/12/2

Y1 - 2008/12/2

N2 - The solubility of sulphur in sulphide-saturated, H2O-bearing basaltic-andesitic and basaltic melts from Hekla volcano (Iceland) has been determined experimentally at 1,050°C, 300 and 200 MPa, and redox conditions with oxygen fugacity (logfO2) between QFM-1.2 and QFM+1.1 (QFM is a quartz-fayalite-magnetite oxygen buffer) in the systems containing various amounts of S and H2O. The S content of the H2O-rich glasses saturated with pyrrhotite decreases from 2,500 ppm in basalt to 1,500 ppm in basaltic andesite at the investigated conditions. Furthermore, the reduction of water content in the melt at pyrrhotite saturation and fixed T, P and redox conditions leads to a decrease in S concentration from 2,500 to 1,400 ppm for basaltic experiments (for H2O decrease from 7.8 to 1.4 wt%) and from 1,500 to 900 ppm (for H2O decrease from 6.7 to 1.7 wt%) for basaltic andesitic experiments. Our experimental data, combined with silicate melt inclusion investigations and the available models on sulphide saturation in mafic magmas, indicate that the parental basaltic melts of Hekla were not saturated with respect to sulphide. During magmatic differentiation, the S content in the residual melts increased and might have reached sulphide saturation with 2,500 ppm dissolved S. With further magma crystallization, the S concentration in the melt was controlled by the sulphide saturation of the magma, decreasing from ∼2,500 to 900 ppm S.

AB - The solubility of sulphur in sulphide-saturated, H2O-bearing basaltic-andesitic and basaltic melts from Hekla volcano (Iceland) has been determined experimentally at 1,050°C, 300 and 200 MPa, and redox conditions with oxygen fugacity (logfO2) between QFM-1.2 and QFM+1.1 (QFM is a quartz-fayalite-magnetite oxygen buffer) in the systems containing various amounts of S and H2O. The S content of the H2O-rich glasses saturated with pyrrhotite decreases from 2,500 ppm in basalt to 1,500 ppm in basaltic andesite at the investigated conditions. Furthermore, the reduction of water content in the melt at pyrrhotite saturation and fixed T, P and redox conditions leads to a decrease in S concentration from 2,500 to 1,400 ppm for basaltic experiments (for H2O decrease from 7.8 to 1.4 wt%) and from 1,500 to 900 ppm (for H2O decrease from 6.7 to 1.7 wt%) for basaltic andesitic experiments. Our experimental data, combined with silicate melt inclusion investigations and the available models on sulphide saturation in mafic magmas, indicate that the parental basaltic melts of Hekla were not saturated with respect to sulphide. During magmatic differentiation, the S content in the residual melts increased and might have reached sulphide saturation with 2,500 ppm dissolved S. With further magma crystallization, the S concentration in the melt was controlled by the sulphide saturation of the magma, decreasing from ∼2,500 to 900 ppm S.

KW - Experiments

KW - Hekla volcano

KW - Saturation

KW - Sulphide

KW - Sulphur

UR - http://www.scopus.com/inward/record.url?scp=65049088012&partnerID=8YFLogxK

U2 - 10.1007/s00410-008-0359-0

DO - 10.1007/s00410-008-0359-0

M3 - Article

AN - SCOPUS:65049088012

VL - 157

SP - 691

EP - 707

JO - Contributions to Mineralogy and Petrology

JF - Contributions to Mineralogy and Petrology

SN - 0010-7999

IS - 6

ER -