3.7 billion year old biogenic remains

Abstract

3.7 Billion year old inclusions inside garnet crystals contain 13C depleted carbonaceous material consistent with biogenic origin. Additional evidence in the form of the other elements of life mainly O, N and P were found to be structural bound to this material by using a new technique, AFM-IR. Here we show additional evidence that support our claim. By overlaying maps generated by the AFM-IR we show how the location of 100's of nm sized contiguous domains of nitrile and possibly phosphonate overlap inside the inclusion. This shows that O, N and P are not only co-localized to the same inclusion but they are co-localized to the same patch of carbonaceous material inside the inclusion. They therefore provide spatial characterization for potentially the oldest biogenic remains in Earth's geological record and corroborates earlier claims for the biogenic origins of carbon in Isua metasediments.

Keywords

• AFM-IR
• Isua supercrystal belt
• nitrile
• phosphonate
• remains of early life