A Gas from the Past

A bit of subterranean detective work has led a U of T geochemist to discover evidence of gases similar to those that may have been on the early Earth, before the origin of life. Geology professor Barbara Sherwood Lollar’s research, published in the journal Nature, has found evidence of abiogenic – or non-life-based – gases in an underground mine near Timmins, Ont. It is a widely held scientific theory that life on Earth probably began from simple organic compounds, including hydrocarbons formed from abiogenic reactions involving water, carbon dioxide and methane. Until now, scientists assumed these abiogenic reactions had been erased by the organic reactions that have dominated Earth since the evolution of complex life. “Until now, these types of gases had been known only through laboratory experimentation and from extraterrestrial samples such as meteorites,” says Sherwood Lollar who believes these gases may be a food source for microbes far below the Earth’s surface.