Rob Knipe1, Steve Freeman1, Simon Harris1, Russell Davies2, Quentin Fisher1, Christine Souque1, Michael Welch1, and Gavin Lewis3
1Rock Deformation Research, Earth Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
2Rock Deformation Research, PO Box 2998, McKinney, TX75070-8998, USA
3Chevron North America, Deepwater Gulf of Mexico, 1500 Louisiana, 77002 Houston, Texas, USA
Understanding along-fault flow is critical to both migration and reservoir flow modelling. However, in most cases, fluid flow is modelled only as an across-fault flow process. This paper reviews the status of research on the processes involved and the predictability of along-fault flow as well as across-fault flow in the context of hydrocarbon migration and accumulation.The flow behaviour in fault zones depends on the following.
· The fault zone architecture – the exact distribution of the faults and stratigraphic dips both within and adjacent to the fault zone.
· The fault zone property architecture – the permeability, capillary, strength and mechanical properties of fault rocks and undeformed units present in and adjacent to the fault zone.Along-fault flow as well as across-fault flow and pressure distributions are all controlled by the three-dimensional spatial distribution of the parameters listed above. The longer-term dynamic behaviour of the fault zone will depend on the stability of these properties during the geo-history.A series of new models for assessing the importance and constraints on these parameters and predicting fault zone flow are introduced. Parameter uncertainty associated with this multi-variable system is used to conduct scenario models for: (a) the prediction of flow behaviour in complex fault zones; (b) the impact of fault zone architectures and uncertainties on modelling fault zone migration; and (c) the prediction of sealing capacities and hydrocarbon column heights.Examples from both outcrops and sub-surface data are also used to highlight the issues required for future understanding and the improved prediction of along-fault flow.
AAPG Search and Discover Article #90066©2007 AAPG Hedberg Conference, The Hague, The Netherlands