Transport behavior in three‐dimensional fracture intersections

Abstract

Flow and transport patterns in three‐dimensional fracture intersections are investigated, with emphasis on the occurrence and effects of local flows around each intersection. Flow and transport simulations indicate that local flow circulations (referred to as “local flow cells”) arise because of an interplay between intersection geometry and corresponding boundary conditions for flow along the fracture boundaries. Local flow cells are thus unique features in three‐dimensional fracture networks. The analysis here suggests that local flow cells have little effect on the overall fluid flow in a fracture network but may constitute an effective mechanism which contributes to the long breakthrough tailing and retardation often observed in transport through discrete fracture networks.