Seminar Series – Dr. Hector Lamadrid: Kinetics of Carbonation Reaction of Ultramafic Rocks

Dr. Hector Lamadrid, University of Missouri

Kinetics of Carbonation Reaction of Ultramafic Rocks: A Geologist Baby Steps Towards the Energy Transition

Serpentinization and carbonation of ultramafic rocks play an important role in the deep volatile cycle on Earth due to the subduction of hydrothermally altered ultramafic rocks, transporting a significant amount of carbon and other volatiles to the deep mantle. Carbonation of ultramafic rocks is also considered a suitable option for long-term geological storage of CO2. Understanding the effect of different PTX conditions on these reactions can contribute to making industrial CO2 more economically feasible and advance our understanding of oceanic hydrothermal systems that are believed to be an essential place for early biological evolution. In this study, I show different applications of a recently developed experimental technique that uses the combination of synthetic fluid inclusions as microreactors and various non-destructive analytical techniques that allows us to obtain kinetic data under various environmental conditions. The method has been successfully used to study the rates of both olivine and pyroxene serpentinization and olivine carbonation reactions at different temperatures, pressures, and fluid compositions. The advantage of this method over more traditional experimental approaches is that it allows detailed micron-scale investigations of fluid-rock interactions and the determination of reaction products and reaction rates in situ, in real-time, with various fluid compositions at elevated temperatures (and pressures) in tens to hundreds of individual microreactors simultaneously. This technique provides new avenues to obtain detailed kinetic and thermodynamic information under different conditions relevant to natural processes and carbon capture and sequestration (CCS). 

Host: Kennet Flores