Figure 6

FT-Raman spectra of the bulk sapropels from Tekirghiol (A), Amara (B) and Ursu lakes (C). Note the highest carotenoid band at 1516 cm−1 in Ursu and completely different spectral profile comprising overlapped contributions from organic material (amorphous carbon, trace of aliphatic and aromatic compounds, photosynthetic pigments). Excitation: 1064 nm. Spectra were background subtracted.