Basic Research Needs for Geosciences - Energetics Meetings and ...

PANEL REPORT: MODELING AND SIMULATION OF GEOLOGIC SYSTEMSCourtesy of Susan Hubbard, LBNLFigure 19. Hydrogeophysical examples. (A): Estimation of hydraulic conductivity obtained using crosshole seismicand radar data conditioned to flowmeter data within a Bayesian framework (datasets and methods described inHubbard et al. 2001). (B): Estimation of sediment geochemistry obtained using crosshole radar amplitude andwellbore measurements within a Markov chain Monte Carlo approach (Chen et al. 2004).difficulties related to provability of a scientific hypothesis (e.g., Oreskes 2000). A data-drivenmodeling paradigm, with continuous updating and error assessment, will move the dialog beyondtheoretical discussions of model validity to a much more useful discussion of the state ofknowledge of a particular system, and to a process of continual model improvement. Such achange of perspective would greatly improve the communication process between scientists,managers, regulators and the public in planning these often contentious projects by providingmuch-needed context for discussions of model validity.Computational chemical thermodynamics—Equilibria and reactionsThe chemical properties of aqueous and nonaqueous fluid phases, their mixtures, and theirinteractions with solid mineral phases are central to the safe storage of nuclear waste and thesequestration of CO 2 in geologic formations, the transport of ore-forming and toxic materials, theexploitation of geothermal energy, and many others. Our knowledge of the relevant subsurfacesystems is adequate for some engineering applications, but a better understanding of the complexstructure of many species in solutions is needed as demands on engineered geological systemsbecome more complex.In recent years there have been dramatic advances in both the theory available to calculate theproperties of complex mixtures and in the performance of computational platforms available forsimulation. These developments, coupled with new high-resolution, analytical measurementsmade possible by high performance light sources and neutron sources, have led to advances inthe understanding of complex materials at an unprecedented level of atomic specificity. A major,new scientific challenge is to build on the remarkable development of these technologies toachieve a new level of understanding and control of processes as diverse as self-organization in58 Basic Research Needs for Geosciences: Facilitating 21 st Century Energy Systems