Implications of reactions between SO2 and basaltic glasses for the mineralogy of planetary crusts
Description
This data accompanies the paper "Implications of reactions between SO2 and basaltic glasses for the mineralogy of planetary crusts", Journal of Geophysical Research, Planets. Abstract: Basalts are ubiquitous in volcanic systems on several planetary bodies, including the Earth, Mars, Venus and Jupiter’s moon Io, and are commonly associated with sulfur dioxide (SO2) degassing. We present the results of an experimental study of reactions between SO2 and basaltic glasses. We examined Fe-free basalt, and Fe-bearing tholeiitic and alkali basalts with a range of Fe3+/Fetotal (0.05 to 0.79) that encompass the oxygen fugacities proposed for most terrestrial planetary bodies. Tholeiitic and alkali basalts were exposed to SO2 at 600, 700 and 800 °C for 1 h and 24 h. Surface coatings formed on the reacted basalts; these contain CaSO4, MgSO4, Na2SO4, Na2Ca(SO4)2, Fe2O3, Fe3O4, Fe-Ti-(Al)-oxides and TiO2. Additionally, the SO2-basalt reaction drives nucleation of crystalline phases in the substrate to form pyroxenes and possible Fe-oxides. A silica-rich layer forms between the substrate and sulfate coatings. More oxidized basalts may readily react with SO2 to form coatings dominated by large Ca-sulfate and oxide grains; if these reactions occur then the products may be detected readily by techniques sampling the upper 10s of microns of the surfaces, such as visible-near infrared and thermal infrared spectroscopy, laser-induced breakdown spectroscopy and X-ray spectrometry. In less oxidized basalts (NNO-1.5 to NNO-5), reactions with SO2 will form thin, fine-grained aggregates of sulfates; such materials are less readily detected by spectroscopy and spectrometry techniques. In contrast, in very reduced basalts (lower than NNO-5), typical of the Moon and Mercury, SO2 is typically a negligible component in the magmatic gas, and sulfides are more likely.
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Steps to reproduce
The nanoSIMS data files .im can be read using the plugin openMIMS in Fiji (recommended) or ImageJ: https://github.com/BWHCNI/OpenMIMS/wiki/Installation Details on experiments and data acquisition are discussed in the accepted paper "Implications of reactions between SO2 and basaltic glasses for the mineralogy of planetary crusts".