In this article we focus on the potential of fault-overlap zones as conduits for fluid flow in a variety of reservoir types. Light detection and ranging (LIDAR) technology were applied to collect a three-dimensional, spatially constrained data set from a well-exposed fault-overlap zone that crops out in the Devil's Lane area of the Canyonlands National Park in Utah. A virtual outcrop was generated and used to extract structural and stratigraphic data that were taken into a reservoir modeling software and reconstructed. The outcrop-based model was flow simulated and used to test fluid flow through a real-world faultoverlap zone. A structural framework was built based on collected outcrop data and combined with a series of nine different fades models. The different fades models included an eolian model based on the outcrop and a range of synthetic fluvial and shallow marine systems. Results show that, for certain depositional models, cross-fault reservoir communication may be poor despite the geometric connectivity of the relay beds. This was the case for low net/gross fluvial models and shoreface models. Conversely, high net/gross fluvial systems and eolian systems show good communication through the same relay zone. Overall, the results show that, in the presence of a fault-overlap zone, pressure communication across a relay ramp may still be poor depending on the scale of the faults and relay ramp as well as the geometry and volume of the sands.
Rotevatn, A., Buckley, S. J., Howell, J. A., & Fossen, H. (2009). Overlapping faults and their effect on fluid flow in different reservoir types: a LIDAR-based outcrop modeling and flow simulation study. AAPG Bulletin, 93(3), 407-427. https://doi.org/10.1306/09300807092