Experimental Modeling of Carbonate Mineral Precipitation in the Presence of Cyanobacteria

International audienceCarbonate mineral precipitation in the presence of cyanobacteria is at the forefront of scientific research due to its importance for understanding paleo-environments of mineral formation and for optimizing conditions of mineralogical CO2 sequestration via biological pathway. Stromatolites are amongst the oldest known biological formations, and they provide insight into early Earth environments and climates. It is therefore essential to understand the processes governing their formation. Numerous field studies were carried out to characterize these bio-formed rocks and their way of formation showing that various parameters could be involved in the processes of formation of carbonate rocks. Thus, reproducing natural environments under laboratory-controlled conditions is an efficient approach to better understand the role of each parameter. The present chapter aims to present some results of these laboratory studies on the biomineralization of Ca, Ca-Mg and Mg carbonates, via analyzing and discussing mechanisms of mineral formation, providing examples of several case studies, assessing, based on available information, the stoichiometry of inorganic carbon removal in the form of carbonate minerals and organic carbon sequestered in the form of bacterial biomass, and finally recommending future research directions in this actively developing field of science