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Low sulfur content in submarine lavas: An unreliable indicator of subaerial eruption

A. S. Davis·D.A. Clague·M. S. Schulz·J.R. Hein
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Abstract

Low S content (<250 ppm) has been used to identify subaerially erupted Hawaiian and Icelandic lavas. Large differences in S content of submarine-erupted lavas from different tectonic settings indicate that the behavior of S is complex. Variations in S abundance in undegassed, submarine-erupted lavas can result from different source compositions, different percentages of partial melting, and crystal fractionation. Low S concentrations in highly vesicular submarine lavas suggest that partial degassing can occur despite great hydrostatic pressure. These processes need to be evaluated before using S content as an indicator of eruption depth.

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A. S. Davis, D.A. Clague, M. S. Schulz, J.R. Hein. 1991. Low sulfur content in submarine lavas: An unreliable indicator of subaerial eruption. https://doi.org/10.1130/0091-7613(1991)019%3C0750%3Alscisl%3E2.3.co%3B2

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