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

GRAND CHALLENGE:INTEGRATED CHARACTERIZATION, MODELING, AND MONITORING OF GEOLOGIC SYSTEMSCourtesy of Susan Hubbard, Lawrence Berkeley National LaboratoryFigure 30: Example of diverse datasets described in Chen et al. (2006a). Seismic velocity and attenuation ofsubsurface media at the Oak Ridge Field Research Center showing high resolution estimates of subsurface zonationthat correspond well with measured hydraulic conductivity measurements. From Hubbard et al. 2006.Relating geophysical measurements to in situ properties/processesThe data required to predict the impact of deep subsurface emplacement of anthropogenic fluidsat the basin scale include 3D seismic reflection data cubes and potential fields (gravity,magnetic). On the aquifer scale, these data may be augmented with geoscience data from welllogs and core-derived rock properties. Fluid communication pathways in the subsurface areidentified using chemical tracers, time-lapse monitoring of geochemical changes in oil andbrines, and pressure transients. Phase changes in the fluids in response to pressure changes canboth be imaged and directly measured in wells.A key scientific challenge addressing deep subsurface disposal consists in part of applying thesestate-of-the-art tools to probe the volume under investigation for a range of physical andchemical properties (e.g., density, bulk modulus, porosity, viscosity, permeability, saturation,concentration). Part of this challenge is to identify new methodologies to represent theseproperties at all scales to predict system performance after perturbation. The performance of thissystem relative to the process of storage will be critically defined by the geological propertiesassociated with fluid flow, geomechanical status (stress, fractures and faults), and their84 Basic Research Needs for Geosciences: Facilitating 21 st Century Energy Systems