Geophysical monitoring of carbon dioxide geological storage in basaltic reservoirs.
Minimizing climate change from increasing atmospheric concentrations of carbon dioxide (CO2) requires dramatic reductions in anthropogenic CO2 emissions. A vital strategy is carbon capture and storage (CCS), also called carbon sequestration. Geological storage, which implies injecting CO2 into underground geologic formations, is currently the most mature storage method. Detailed site characterization and reliable monitoring are crucial aspects for successful CO2 geologic storage. My research focuses on applying geophysical methods for these purposes. Although there are successful examples of geophysical monitoring of CO2 plume propagation, quantifying the amount of CO2 underground remains a challenging task. My major goal is to develop viable monitoring techniques using a complex of geophysical methods, such as well logging, petrophysical analysis and seismic surveys.
In a number of recent studies, basaltic rocks have been proposed as a promising target for CO2 storage. Unlike sedimentary aquifers, basalts have a high potential for geochemical trapping, which involves long-term reactions of CO2 with host rocks and the formation of stable minerals such as carbonates under in situ conditions. Massive continental flood basalts exist on many continents and represent a potentially important host medium for CO2 geological sequestration, especially in regions where conventional storage options in sedimentary basins are limited. As a part of my dissertation I am conducting pre-injection reservoir characterization based on well logging data for a pilot CO2 sequestration project in the Columbia River flood basalts (Washington, USA). This project is one of the first field tests specifically designed to confirm the feasibility of permanently and safely sequestering of CO2 within deep flood basalt formations. An accurate petrophysical analysis is crucial for describing reservoir properties and characterizing its storage capacity and containment, as well as for establishing base-line conditions for future post-injection monitoring.
One of the greatest challenges will be monitoring of basalt mineralization due to CO2 injection. I am currently investigating the feasibility of applying an innovative approach for mineralization monitoring using borehole elemental spectroscopy measurements and core analysis (including infrared spectroscopy and geochemical data).