Figure 8.

(A) BAC (Bacalar microbialite) mineral inclusions and embedding organic matter (top, scanning electron micrograph), (B) SR-FTIR spectra of surface locations rich in EPS and EPS plus minerals of fresh BAC microbialite, (C) SR-FTIR spectromicroscopy images (200 μm by 150 μm) showing the distribution of microbes and minerals in a living BAC microbialite. Distribution heat maps of the protein amide II vibration modes at ~1,542 cm⁻¹, the carbohydrates vibration modes at ~1,000 cm⁻¹, calcite at ~870 cm⁻¹, and lipid is base on the CH vibration modes near 2,900 cm⁻¹. Scale bars: 10 μm. Transmittance is given in % units.