Methane Converted to Abiogenic Oil in Mantle-like Conditions
Posted by Jeff Id on July 27, 2009
We’ve heard it before, but this sounds like a bit of progress. It makes you wonder.
The oil and gas that fuels our homes and cars started out as living organisms that died, were compressed, and heated under heavy layers of sediments in the Earth’s crust. Scientists have debated for years whether some of these hydrocarbons could also have been created deeper in the Earth and formed without organic matter. Now for the first time, scientists have found that ethane and heavier hydrocarbons can be synthesized under the pressure-temperature conditions of the upper mantle —the layer of Earth under the crust and on top of the core.
The research was conducted by scientists at the Carnegie Institution’s Geophysical Laboratory, with colleagues from Russia and Sweden, and is published in the July 26, advanced online issue of Nature Geoscience.
Now, a team led by Alexander Goncharov at the Carnegie Institute of Washington in the US, say they have provided solid experimental data that support these predictions. ‘What we found, for the first time, is the transformation of methane to heavy hydrocarbons like propane or butane, under upper mantle conditions,’ says Goncharov.
Furthermore, the researchers recognise that this is just the first of many steps in building a case that supports an abiogenic origin of hydrocarbons. ‘We are in preparation for doing more experiments with more complex systems, including minerals which are relevant for the upper mantle earth,’ explains Goncharov. ‘An obvious consequence of our work could be that we might have more oil in the Earth than has been expected, but that’s highly speculative’ he adds.