Sulfate-methane transition as a proxy for average methane hydrate saturation in marine sediments

We develop a relationship between the sulfate-methane transition (SMT) and average gas hydrate saturation (AGHS) for systems dominated by methane migration from deeper sources. The relationship is explained by a one-dimensional numerical model that simulates gas hydrate accumulation in marine sediments. Higher methane fluxes result in shallow SMT depths and high AGHS, while lower methane fluxes result in deep SMTs and low AGHS. We also generalize the variation between AGHS and scaled SMT depth, a procedure that aids prediction of AGHS at different sites from observations of the SMT, such as along Cascadia Margin.