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

GRAND CHALLENGE: SIMULATION OF MULTISCALE GEOLOGIC SYSTEMS FOR ULTRA-LONG TIMES3. Data IntegrationFor many subsurface applications, the model must be capable of using real-time information toupdate predictions, to inform field-scale deployment of monitoring methods, and toquantitatively assess the data. Data integration requires measurements from the laboratory to thefield scale. In particular:• Laboratory experiments need to be designed to provide scale-appropriate information undercontrolled conditions. These provide the best potential for validating mathematicalformulations and calibrating numerical methods for complex processes and media.• Coupling across multiple scales needs to be tested, which will require the integration of dataacquired at multiple scales—from the laboratory to the field scale.• Time-lapsed data has to be integrated into the numerical models.4. Coordination with other priority research directionsCoordination with other priority research directions is required to achieve an accuraterepresentation of the physics, chemistry and biology at different scales for development ofmodels that will couple information across scales. Specific length and time scale information willinclude (but is not limited to): quantitative chemical reaction rates, the role of interfaces (fluidfluid/ fluid-solid) on multiphase transport, microbial-solid interaction rates, chemical migration,and time-lapsed data of evolving systems.SCIENTIFIC IMPACTSThe fundamental importance of heterogeneity on all scales in natural systems suggests thatresearch in this area will have broad scientific impact on subsurface science. For example,insofar as permeability heterogeneity controls fluid flow, heterogeneity exerts a profound controlon key processes in a wide range of subsurface systems. From the pore scale to the basin scale,heterogeneity may lead to emergent behavior not readily predicted from process descriptionsrestricted to one scale or another.Research into impacts of heterogeneity over multiple scales will aid in the understanding of theorigin of residual saturation, a key mechanism of CO 2 trapping. At the pore level, fluid phasesare subject to entrapment and bypassing of existing fluids. Predicting residual saturations andtheir evolution with time across multiple scales is important for estimating the capacity of CO 2storage sites and predicting brine displacement. From pore-level studies, we can derive accurateparameterizations (e.g., hysteretic relative permeability and capillary pressure curves) needed forreservoir and basin-scale models.Critical to reactive transport modeling at the pore scale is accurate modeling of pore-fluidcomposition. The spatial averaging concepts inherent in Darcy’s law do not suffice fordescribing fluid composition at fluid-mineral interfaces where reactions occur. Feedback ofreactions on pore geometry and fluid compositions propagates to larger length and time scales.The importance of reactive multiphase flow processes at various scales depends to a large degreeon the questions being asked and the data available. Research in this area will allowidentification of dominant processes and length and time scales over which they operate,102 Basic Research Needs for Geosciences: Facilitating 21 st Century Energy Systems