Serpentinization and the Formation of H(2) and CH(4) on Celestial Bodies (Planets, Moons, Comets)

Serpentinization involves the hydrolysis and transformation of primary ferromagnesian minerals such as olivine ((Mg,Fe)(2)SiO(4)) and pyroxenes ((Mg,Fe)SiO(3)) to produce H(2)-rich fluids and a variety of secondary minerals over a wide range of environmental conditions. The continual and elevated production of H(2) is capable of reducing carbon, thus initiating an inorganic pathway to produce organic compounds. The production of H(2) and H(2)-dependent CH(4) in serpentinization systems has received significant interdisciplinary interest, especially with regard to the abiotic synthesis of organic compounds and the origins and maintenance of life in Earth's lithosphere and elsewhere in the Universe. Here, serpentinization with an emphasis on the formation of H(2) and CH(4) are reviewed within the context of the mineralogy, temperature/pressure, and fluid/gas chemistry present in planetary environments. Whether deep in Earth's interior or in Kuiper Belt Objects in space, serpentinization is a feasible process to invoke as a means of producing astrobiologically indispensable H(2) capable of reducing carbon to organic compounds. Key Words: Serpentinization—Fischer-Tropsch-type synthesis—Hydrogen formation—Methane formation—Ultramafic rocks. Astrobiology 15, 587–600.