Signatures of early microbial life from the Archean (4 to 2.5 Ga) eon

  title={Signatures of early microbial life from the Archean (4 to 2.5 Ga) eon},
  author={Kevin Lepot},
  journal={Earth-Science Reviews},
  • K. Lepot
  • Published 22 July 2020
  • Geology
  • Earth-Science Reviews
Abstract The Archean era (4 to 2.5 billion years ago, Ga) yielded rocks that include the oldest conclusive traces of life as well as many controversial occurrences. Carbonaceous matter is found in rocks as old as 3.95 Ga, but the oldest (graphitic) forms may be abiogenic. Due to the metamorphism that altered the molecular composition of all Archean organic matter, non-biological carbonaceous compounds such as those that could have formed in seafloor hydrothermal systems are difficult to rule… Expand
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