Geologic fractures are always under significant overburden stress. While stress has been shown to impact fluid flow through fractured media in a fundamental way, the impact of stress on tracer transport have not been investigated well.
We recently demonstrated that an increase in the normal stress on a rough fracture can induce anomalous transport. Normal stress transforms the fracture geometry from a relatively homogeneous to a very heterogeneous flow structure: as the mean fracture aperture decreases, the flow self-organizes into preferential-flow channels and stagnation zones. We are extending this line of research to discrete fracture networks. Figure below shows the emergence of preferential flow paths caused by change in stress orientation.
More details will be updated soon.