Migration of CO2 plume and reactions of injected CO2 with rocks in the Sleipner CO2 storage site, North Sea
Speaker: Pei-Hua Hsu
Abstract
Anthropogenic greenhouse-gas emissions continue to increase rapidly, and this is thought to be causing enhanced global warming. One potentially long-term solution for offsetting these emissions is the capture and storage of carbon dioxide into geological formations. The storage position is generally proposed to be injected at more than 800 meters depth, where carbon dioxide is in a supercritical state. Supercritical carbon dioxide is buoyant with respect to host rock and aqueous fluids at relevant temperatures and pressures. So the buoyant carbon dioxide fluid may migrate back to the surface. For a long-term stability of carbon dioxide storage, it needs to simulate the behavior of the injected carbon dioxide by providing the physical and chemical properties of sites. The Utsira Sand in the Sleipner Field, for an example, it is the world's first industrial-scale carbon dioxide storage operation and carbon dioxide is being injected at a depth of about 1000 meters into the Utsira Sand (as a reservoir), a regional saline aquifer, which is covered by a 250 meters thickness shale (as a caprock), the Nordland Group. For carbon dioxide storage, they need to draw some physical and chemical characterizations, such as geological structure, stratigraphic architecture, porosity and mineral composition based on seismic data, well-log, SEM, and XRD analysis for a longer-term migrant simulation of the injected carbon dioxide accumulated beneath different stratum. At last, they discuss both how the migration influences by geological formations and the reaction of the bottom of the caprocks.
Reference
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