This artistic view of the Earth's interior shows hydrocarbons forming in the upper mantle and transported through deep faults to shallower depths in the Earth's crust. The inset shows a snapshot of the methane dissociation reaction studied in this work. (Credit: Image courtesy A. Kolesnikov and V. Kutcherov)
From Science Daily:
ScienceDaily (July 27, 2009) — 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.
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