Microbes and lacustrine carbonates: The good, the bad and the ugly?

Daniel Ariztegui - University of Geneva

Investigations in living microbialites are providing significant data that are critical to disentangle the role of the various biotic and abiotic processes contributing to their development. Despite these efforts separating the impact and magnitude of these processes remain a difficult task.
Field and laboratory studies in modern lacustrine environments from the Andes to the Alps show that extrinsic – environmental – factors might have a changeable impact over short periods of time switching mineral precipitation from biotic to abiotic and vice-versa. Such switch may or may not be distinguishable in fossilized microbialites.