AAPG Student Chapter Talk

Quentin Fisher, Professor of Petroleum Geoengineering, and one of Petroleum Leeds' Research Directors, will be giving a talk on "Impact of faults on fluid flow in petroleum reservoirs".

Abstract: Fault-related hydrocarbon seeps and mineralisation provide ample evidence that faults sometimes act as conduits for fluid flow. Indeed, mud loses and increased rates of petroleum production frequently occur in some reservoirs at positions where well bores intersect faults. Production data from petroleum reservoirs, however, also provides strong evidence that faults sometimes also act as barriers to fluid flow. It has often been suggested that this paradoxical behaviour is related to fault activity: active faults are often regarded as being conduits for flow whereas inactive faults are regarded as being barriers to fluid flow. Examination of the microstructure of >3000 faults from >500 petroleum reservoirs throughout the world indicates, however, that factors such as stress conditions, stress history and rheology of the reservoir at the time of faulting often have a more important influence on whether a fault acts as a conduit or a barrier to fluid flow than whether or not it is active.

Optimizing production strategies and identifying unswept compartments or totally new exploration targets not only requires information on whether or not a fault will act as a barrier or conduit – it requires far more detail information on the likely flow rates that can be achieved on a range of time scales (10 to >10⁶ years). The presentation will provide details of current methods that are used to predict likely cross-fault flow rates but more importantly how to calibrate these methods using static and dynamic data obtained from petroleum reservoirs.