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A range of unfaulted and faulted bed-scale models with sheet-like bed geometries have been built and analysed in terms of static bed connectivity and fractional permeability assuming permeable sands and impermeable shales. The models are built using a new method which allows amalgamation ratio to be included explicitly as model input and this property, rather than net:gross ratio, is found to be the dominant control on inter-bed connectivity. The connectivity of faulted sequences is much more complex and is dominated by interactions of variables. A comprehensive modelling suite illustrates these results and highlights the extremely rare combinations of circumstances in which faulted sequences have lower connectivities than their unfaulted sedimentological equivalents, irrespective of whether fault rock properties are included or not. In general, models containing stochastically placed shale smears associated with each faulted shale horizon are better connected than if deterministic Shale Gouge Ratio cut-offs are applied. Despite the complex interactions between geological input and bed-scale connectivity, the flow properties of a system are controlled by only three geometrical, rather than geological, variables describing connectivity, anisotropy and resolution. If two different faulted or unfaulted systems have identical values of these three variables they will have the same flow properties. Not applicable Amerada Hess, BG Energy, BP Exploration, ConocoPhillips, Kerr-McGee North Sea, Shell, Statoil and Total

Post-depositional normal faults within the turbidite sequence of the Late Miocene Mount Messenger Formation of the Taranaki basin, New Zealand are characterised by granulation and cataclasis of sands and by the smearing of clay beds. Clay smears maintain continuity for high ratios of fault throw to clay source bed thickness (c. 8), but are highly variable in thickness, and gaps occur at any point between the clay source bed cutoffs at higher ratios. Although cataclastic fault rock permeabilities may be significantly lower (c. 2 orders of magnitude) than host rock sandstone permeabilities, the occurrence of continuous clay smears, combined with low clay permeabilities (10's to 100's nD) means that the primary control on fault rock permeability is clay smear continuity. A new permeability predictor, the Probabilistic Shale Smear Factor (PSSF), is developed which incorporates the main characteristics of clay smearing from the Taranaki Basin. The PSSF method calculates fault permeabilities from a simple model of multiple clay smears within fault zones, predicting a more heterogeneous and realistic fault rock structure than other approaches (e.g. Shale Gouge Ratio, SGR). Nevertheless, its averaging effects at higher ratios of fault throw to bed thickness provide a rationale for the application of other fault rock mixing models, e.g. SGR, at appropriate scales. Not applicable Amerada Hess, BG Energy Holdings, BP Exploration, ConocoPhillips, Kerr-McGee North Sea, Shell, Statoil and Total.