Underground Metal-Munching Microbes Can Help Explore and Recover Oil and Gas

Researchers found that Halomonas, an underground metal-munching bacteria can help explore and recover oil and gas.

Halomonas are underground metal-munching bacteria that have dominated deep sandstone formations because of their unique traits. They can withstand heat, high salinity, low oxygen, utter darkness and pressures that would kill most other organisms. This makes them adaptable to any living condition. However, not much is known about these microbes.

Therefore, Bruce Fouke, a professor of geology and of microbiology at the University of Illinois at Urbana-Champaign, undertook a study to shed more light on the diversity of underground microbes.

"Astonishingly little is known of this vast subsurface reservoir of biodiversity, despite our civilization's regular access to and exploitation of subterranean environments," he said in a press statement.

For the study, researchers from the University of Illinois collected microbial samples from a sandstone reservoir 1.8 kilometers below the surface. Using a probe developed by the oilfield services company Schlumberge, researchers sampled sandstone deposits of the Illinois Basin. This sampling revealed "a low-diversity microbial community dominated by Halomonas sulfidaeris-like bacteria that have evolved several strategies to cope with and survive the high-pressure, high-temperature and nutrient deprived deep subsurface environment," Fouke stated.

They found that these microbes were able to make use of iron and nitrogen from their surroundings for their own nutritional needs. What makes the discovery all the more interesting is that Halomonas are capable of metabolizing aromatic compounds, a common component of petroleum.

"This means that these indigenous microbes would have the adaptive edge if hydrocarbon migration eventually does occur," Fouke said. "This will enhance our ability to explore for and recover oil and gas, and to make more environmentally sound choices for subsurface gas storage."