Figure 7: X-ray absorption spectra of Gunflint organic microfossils.
The atomic N/C ratios (±0.010) shown here have been estimated following the methodology developed by Alleon et al.47. The absorption spectra of modern cyanobacteria (G. violaceus) and of modern micro-algae (E. gracilis) are shown for comparison. Absorption features observed in the 340–360 eV range indicate the presence of calcium.
