Evidence Against Hydrogen-Based Microbial Ecosystems in Basalt Aquifers
Robert T. Anderson,
Francis H. Chapelle,
Derek R. Lovley
*
It has been proposed that hydrogen produced from
basalt-ground-water interactions may serve as an energy source
that supports the existence of microorganisms in the deep subsurface on
Earth and possibly on other planets. However, experiments demonstrated that hydrogen is not produced from basalt at an environmentally relevant, alkaline pH. Small amounts of hydrogen were produced at a
lower pH in laboratory incubations, but even this hydrogen production
was transitory. Furthermore, geochemical considerations suggest that
previously reported rates of hydrogen production cannot be sustained
over geologically significant time frames. These findings indicate that
hydrogen production from basalt-ground-water interactions may not
support microbial metabolism in the subsurface.
R. T. Anderson, Department of Civil and Environmental
Engineering, University of Massachusetts, Amherst, MA 01003, USA.
F. H. Chapelle, U.S. Geological Survey, Columbia, SC 29210-7651,
USA. D. R. Lovley, Department of Microbiology, University of
Massachusetts, Amherst, MA 01003, USA.
*
To whom correspondence should be addressed. E-mail:
dlovley{at}microbio.umass.edu.
