Methane is a potent greenhouse gas with a multitude of biological as well as non-biological sources. It is also one of the main targets for NASA and European/Russian missions on Mars. One of the most exciting recent advances in understanding Earth’s methane cycle has been the recognition that methane seepage from marine seabed is globally widespread. The primary sink of this methane, which prevents the vast majority of it being released into the water and into the atmosphere, is consumption in sediment by ‘methanothrophic’ archaea. These archaea often work together with sulfate reducing bacteria to consume the methane and produce calcium carbonate rock and sulfide. An important reservoir of methane are gas hydrates, which exist of solid methane/water complexes under specific temperature/pressure conditions in marine sediments.
Check out the abundant shallow methane seepage environments on Dublin’s doorstep, just a few kilometres into the Irish Sea by these papers I authored and co-authored;
Also check out these cool videos from the E/V Nautilus on the East coast of North America.