Mining the seafloor

Scientists at the US Department of Energy’s

have recreated the high-pressure, low-temperature conditions of the seafloor in a tabletop apparatus for the study of methane-hydrates, an abundant, but currently out-of-reach, source of natural gas trapped within sediments below the ocean floor.

‘The amount of natural gas that is tied up in methane hydrates beneath the seafloor and in permafrost on Earth is several orders of magnitude higher than all other known conventional sources of natural gas — enough to meet our energy needs for several decades,’ Brookhaven chemist Devinder Mahajan said.

But extracting this resource poses several challenges.

For one thing, methane hydrates - which are ice-like cages made of water molecules surrounding individual methane molecules - are only stable at the very low temperatures and high pressures present at the ocean floor. ‘If you try to bring it up, these things fizzle and decompose, releasing the trapped methane,’ Mahajan says.