Conventional methods of quantitative reservoir characterization are inappropriate when confronted with the complex ripple-scale (millimetric to centimetric scale) intercalations of sand and shale that are characteristic of heterolithic facies. This paper presents a new methodology for quantifying single-phase fluid flow behaviour in heterolithic facies by defining, for discrete heterolithic lithofacies types, effective permeabilities at Representative Elementary Areas (REAs). REA graphs are defined by calculating effective permeabilities at increasing scales, using the renormalization approach. Given that effective permeability values in these facies are dominated by sand connectivity, these REAs are based on binary sand-shale indicator maps derived from constant-scale photography at outcrop. The heterolithic facies studied produce REAs at characteristic scales of around 20,000 cm2. REA based effective permeabilities in different directions show comparable areal dimensions, but significantly different permeability values. REA based effective permeabilities can subsequently be modelled in inter-well volumes through the use of various indicator based pattern recognition procedures. A methodology is presented for developing realistic "training" patterns of heterolithic lithofacies through outcrop photography.

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