ABSTRACT:
During the development of conceptual geosphere models for potential candidate sites for deep geologic repositories, in-depth understanding of multi-disciplinary geoscientific information (geological, lithological, hydrological, geomechanical, etc.) must be acquired. The Moderately Fractured Rock (MFR) experiment, part of Ontario Power Generation’s Deep Geologic Repository Technology Program (DGRTP), has provided an ideal opportunity to demonstrate characterisation, integration and simulation technology because of the large, complex and multidisciplinary data set that has been developed. The MFR dataset is extensive since a tremendous amount of study has been conducted over the last several years pertaining to the geology, lithology, hydrogeology, geophysics, geochemistry and the geomechanics of the local rockmass. Given the large data sets available, an illustrative case study of stress control on anisotropy in the permeability field of the MFR experimental area has been undertaken. Through this work, it is demonstrated that stress may play an important role in controlling the anisotropy of the MFR’s permeability field. An improved understanding has been attained as to how fluid could move through the MFR by relating the existing fracture pathways with the contemporary stress field and observations of measured hydraulic responses.
1 INTRODUCTION
1.1 3D geoscience visualisation for the moderatelyfractured rock experiment
As part of Ontario Power Generation’s (OPG’s) Deep Geologic Repository Technology Program, a pilot-level project was initiated (3D Geoscience Visualization (Phase I)) to explore the application of Virtual Reality (VR) technology for conceptual geosphere model development (Cotesta & Kaiser 2002). The data used in this study was from the Moderately Fractured Rock (MFR) experiment at the Underground Research Laboratory (URL) in Pinawa, Manitoba (Fig. 1). Site characterization and modelling activities produced a data set that was both complex and multi- disciplinary combining observational, modelled and interpreted data for a 125,000 m3 block of fractured plutonic rock.
