In this project we propose to study the adsorption of methane onto a model mineral surface. This type of study is crucial to the understanding of the temperature dependence of the amount of methane stored on submarine mineral surfaces. The ultimate aim is to determine the adsorption isotherms for methane on various surfaces over a range of salinity. The specific experiments proposed in this application will also be used to deduce the composition of the aqueous medium (i.e. the H2O/D2O ratio) that will give the most information on the thickness and density of the adsorbed methane layer. Once these compositions are determined, experiments will be completed, using this contrast, to determine the adsorbed amount of methane on sapphire surfaces at various temperatures and salt concentrations.