Flipkens et al. (2023): Enhanced olivine dissolution in seawater through continuous grain collisions

Gunter Flipkens, Michael Fuhr, Géraldine Fiers, Filip J.R. Meysman, Raewyn M. Town, Ronny Blust IN: Geochimica et Cosmochimica Acta 359,84-99, https://doi.org/10.1016/j.gca.2023.09.002

Coastal enhanced silicate weathering is one of the proposed CDR techniques that aims to accelerate the natural process of CO2-sequestration during marine chemical weathering of silicate minerals. To this end, finely ground rock containing olivine (MgxFe2−xSiO4) could be dispersed in dynamic coastal environments, where local biotic and abiotic factors potentially enhance the weathering process. However, accurate predictions of the olivine dissolution rate and the associated CO2 sequestration under in situ conditions are currently lacking and ecosystem impacts remain to be assessed. Previously, it has been hypothesized that in situ grain collisions, induced by bed load transport due to currents and waves, could accelerate the in situ chemical weathering of olivine particles. To examine this, the authors investigated the effects of continuous grain tumbling on olivine dissolution in natural seawater.