Geochemistry and the Origin of Life

Abelson Acad Acta algal alkanes amino acids amounts analyses atmosphere benzene billion biogenic biological Bulawayan carbon isotopic carbonaceous chondrites Chem chemical evolution chemistry chromatographic composition concentration contain Cosmochim deposits distribution E. S. Barghoorn Early Precambrian equilibrium evidence extractable organic fatty acids fossils fraction free oxygen gas chromatographic Geochim Geol geologic Gunflint chert H₂O Hoering hydrocarbons hydrogen indicate iron formations isoprenoid kerogen Kvenvolden limestone material MEINSCHEIN methane microfossils minerals mixture Mokoia molecules morphological Murchison meteorite Murray n-alkanes NAGY Nonesuch Nonesuch shale NOONER ocean Onverwacht organic compounds organic geochemistry organic matter Orgueil meteorite origin ORÓ oxidation oxygen paper peaks photosynthesis porphyrins Precambrian present primitive earth pristane pristane and phytane ratio reaction reported residue sample Science sedimentary rocks sediments shale solvent South Africa spheroids stromatolitic structures studies suggested sulfur surface Swaziland System synthesis Table temperature terrestrial tion uraninite Urey values volcanic gases µg/g