image: Photo of unit 4 of the Xiamaling Formation where recycled petrographic carbon was identified. view more
Credit: Image credit: Donald E. Canfield
Researchers performed Raman spectral analysis on samples from nine geological formations dating from 742 to 1729 million years ago and used the extent of organic matter recycling as a proxy for atmospheric oxygen levels during the Proterozoic Eon; the study estimates that minimum oxygen levels during the Proterozoic Eon were 2-20% of present levels, suggesting that oxygen levels likely did not hinder the evolution of eukaryotes and early animals during this time.
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Article #2021-01544: "Petrographic carbon in ancient sediments constrains Proterozoic Era atmospheric oxygen levels," by Donald E. Canfield et al.
MEDIA CONTACT: Donald E. Canfield, University of Southern Denmark, Odense, DENMARK; tel: (45) 65 50 27 51; email: dec@biology.sdu.dk
Journal
Proceedings of the National Academy of Sciences