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Abstract The mainly deep-submarine Ontong Java Plateau (OJP) is the result of the largest outpouring of lava in the geologic record. Volcanic events of this magnitude can have dramatic environmental impacts due to volatile emissions. We report new S measurements in naturally glassy, olivine-hosted melt inclusions and pillow basalt glasses from the OJP. We combined these data with previous S measurements in OJP glasses to quantify S degassing in a suite of OJP glasses. Comparison with an S degassing model suggests OJP lavas that erupted at depths ~>1500 m did not degas S; OJP lavas that erupted at depths ~<1500 m degassed up to ~40% initial S, but these lavas likely made up a small fraction of OJP lavas. This result suggests that despite its large volume compared to continental large igneous provinces (LIPs), OJP lavas emitted less S, potentially contributing to its muted environmental impact. The OJP may provide a framework for the temporal evolution of S degassing at oceanic LIPs, with early eruptions at great water depths releasing limited to no S, and later eruptions at shallow water depths releasing larger, but still limited amounts of S. This framework may also have implications for continental LIP magmas, which may release significant amounts of CO2 but limited amounts of S during intrusive activity, with magmatic S emissions only becoming important during extrusive phases.
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Sulfur_X: A Model of Sulfur Degassing During Magma Ascent
Key Points Sulfur_X is a new open‐source magma degassing model that accurately predicts the volatile and redox evolution of ascending arc magmas Sulfur_X shows that sulfur can start degassing in the lower crust or near‐surface, depending on the initial S 6+ /ΣS and H 2 O in the melt The vapor compositions predicted by Sulfur_X can be used to interpret the CO 2 /S T ratios in high‐ T volcanic gases, an eruption precursor
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- PAR ID:
- 10459039
- Date Published:
- Journal Name:
- Geochemistry, Geophysics, Geosystems
- Volume:
- 24
- Issue:
- 4
- ISSN:
- 1525-2027
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1029/2022GC010552
