The solubility of magnesium-hydroxide sulfate-hydrate in seawater at elevated temperatures and pressures.

Abstract

The stability of magnesium-hydroxide-sulphate-hydrate (MHSH) over a range of T-P is evaluated from results of experiments to estimate its thermochemical parameters and determine its solubility. Chemical mass balance calculations and mineral stability data indicate the existence of at least two distinct MHSH stoichiometries. The experimental data impose significant constraints on the interpretation of sea-water-basalt interaction experiments and the study of hydrothermal fluids and associated mineralogy of oceanic ridge crests.-M.S.