A major issue to be resolved when modeling CO2 spreading and
trapping in relation to geological storage, is the broad range of spatial and temporal scales that need to be addressed. Spatial scales range from the scale of pores, relevant for processes like viscous fingering and for many geochemical processes, to the scale of a whole basin, relevant for issues such as brine migration, mechanical stability or reservoir capacity. Temporal scales range from fractions of seconds,
which is relevant for many geochemical processes, to days and weeks, a typical duration of a field test, to decades, which is the expected duration of industrial injections, to periods of geologic when analyzing the final stabilization. No model can represent the details of all phenomena at all scales. Instead, one needs to seek effective or upscaling approaches, i.e. approaches that capture the essence of the phenomenon modeled in a simplified manner. The problem lies in the fact that geological heterogeneities cause the relevant coupled physical, chemical and mechanical processes to be important at different scales and their effective parameters to become scale-dependent, but in different ways.

This session invites all contributions addressing the issues of scale and approaches for upscaling in the modeling and data analysis of geological storage of CO2.