TY - JOUR
T1 - Prokaryotes stimulate mineral H2 formation for the deep biosphere and subsequent thermogenic activity
AU - Parkes, R. John
AU - Linnane, Cathal D.
AU - Webster, Gordon
AU - Sass, Henrik
AU - Weightman, Andrew J.
AU - Hornibrook, Ed R.C.
AU - Horsfield, Brian
PY - 2011/3
Y1 - 2011/3
N2 - The deep subseafloor biosphere contains two-thirds of Earth's prokaryotic biomass, which may indicate the presence of novel mechanisms of energy generation as temperatures increase in the subsurface. In sediment slurry experiments (0-100 °C) with a range of common minerals and rocks (including basalt and quartz), there is significant H2 formation at elevated temperatures, but only in the presence of prokaryotes. This stimulates further prokaryotic activity, typical of deep sediments (sulfate reduction, acetogenesis, and CO2 production, plus continuing methanogenesis), and Bacteria and Archaea representative of many deep sediment types develop. H2 and acetate formation is particularly stimulated above 70 °C. This prokaryotic activity even enhances reactions when temperatures are raised to thermogenic levels (~125-155 °C), including hydrocarbon generation. Mechanochemistry may be important for mineral H2 formation; this is enhanced by prokaryotes (biomechanochemistry), and subsurface stress and fracturing, which is widespread on Earth.
AB - The deep subseafloor biosphere contains two-thirds of Earth's prokaryotic biomass, which may indicate the presence of novel mechanisms of energy generation as temperatures increase in the subsurface. In sediment slurry experiments (0-100 °C) with a range of common minerals and rocks (including basalt and quartz), there is significant H2 formation at elevated temperatures, but only in the presence of prokaryotes. This stimulates further prokaryotic activity, typical of deep sediments (sulfate reduction, acetogenesis, and CO2 production, plus continuing methanogenesis), and Bacteria and Archaea representative of many deep sediment types develop. H2 and acetate formation is particularly stimulated above 70 °C. This prokaryotic activity even enhances reactions when temperatures are raised to thermogenic levels (~125-155 °C), including hydrocarbon generation. Mechanochemistry may be important for mineral H2 formation; this is enhanced by prokaryotes (biomechanochemistry), and subsurface stress and fracturing, which is widespread on Earth.
UR - http://www.scopus.com/inward/record.url?scp=79951718091&partnerID=8YFLogxK
U2 - 10.1130/G31598.1
DO - 10.1130/G31598.1
M3 - Article
AN - SCOPUS:79951718091
SN - 0091-7613
VL - 39
SP - 219
EP - 222
JO - Geology
JF - Geology
IS - 3
ER -