Hydrogeochem

Aqueous Geochemistry, Reactive Transport, and Tracers

Reactive transport involves physical and chemical processes that occur as fluids flow through geologic formations, resulting in complex feedbacks between flow and chemical reactions. Assistant Professor Andrew Luhmann and MS student Zhidi Wu are currently conducting flow-through fluid-rock interaction and mechanical experiments to assess coupled chemical-mechanical degradation in geologic carbon sequestration environments. Experiments at reservoir temperature and pressure are conducted on Pennsylvanian Morrow B Sandstone cores from the Farnsworth Field in Texas (Southwest Regional Partnership on Carbon Sequestration site), and will identify how cement composition and texture impact mechanical property changes due to reaction with CO₂-rich brine.

Preferential flow paths, such as the critical path shown above, can accommodate much of the flow through geologic samples, and thus control locations of chemical reactions. This fluid-rock reaction modifies flow pathways, impacting subsequent flow and reactive transport. Figure from Luhmann et al. (2017, WRR).