THE INTERNAL ARCHITECTURE ANDPERMEABILITY STRUCTURES OF FAULTS INSHALE FORMATIONS
Résumé
The evaluation of fluid flow through fractures and faults is of primary importance for thelong-term performance assessment of radioactive waste repositories in shale formationsand could be used to assess CO2 storage security or the integrity of caprocks and reservoircapacity. This study focuses on the structural evolution within brittle to ductileshear zone in order to understand permeability enhancement and sealing processesaffecting a strike-slip fault system within the Toarcian shale formation from the TournemireUnderground Research Laboratory (URL), southern France. A combination ofquantitative field measurements and laboratory and in situ experiments was used to estimatethe fluid-flow properties of a fractured shale formation. Results indicate that microfracturesgovern the matrix porosity in the damagezone and play an increasingly dominantrole in fluid flow along the boundary between fault core and fault damage zone.
