H2O Exsolution Research Articles

A Model for Predicting the Volumes of Vesicles in Submarine Basalts

The total volume percentage of vesicles in submarine pillow basalt rinds can be modelled by the exsolution of H₂O and CO₂ vapor, using available solubility determinations for these components in basalt. In accordance with observations on natural samples, CO₂ is predicted to be the major vapor component in vesicles at eruption depths > 1-2 km. Only small initial contents of CO₂ (0.1-0.2 wt %) are consistent with the vesicle volumes observed in most deep sea pillow lavas. H₂O is important only at shallow depths. Crystallization of pillow interiors can lead to more extensive vesiculation inside of pillow lavas than in the vesicle-poor outer rinds.