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a b s t r a c tCharacterising fractures at outcrop for use as analogues to fractured reservoirs can use several methods. Four important fracture data collection methods are linear scanline sampling, areal sampling, window sampling and circular scanline sampling. In regions of homogeneous fracture networks these methods are adequate to characterise fracture patterns for use as outcrop analogues, however where fractures are heterogeneous, it is more difficult to characterise fracture networks and a different approach is needed.We develop a workflow for fracture data collection in a region of heterogeneous fractures in a fold and thrust belt, which we believe has applicability to a wide variety of fracture networks in different tectonic settings. We use an augmented circular scanline method, along with areal sampling to collect a range of fracture attribute data, including orientation, length, aperture, spatial distribution and intensity. This augmented circular scanline method more than halves the time taken for data collection, provides accurate, unbiased data that is representative of local fracture network attributes and involves data collection of a wider range of fracture attributes than other sampling techniques alone.

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a b s t r a c tIn fold-and-thrust belts rocks undergo deformation as fold geometries evolve. Deformation may be accommodated by brittle fracturing, which can vary depending on structural position. We use 2D forward modelling and 3D restorations to determine strain distributions throughout folds of the Achnashellach Culmination, Moine Thrust Belt, NW Scotland. Fracture data is taken from the Torridon Group; a thick, coarse grained fluviatile sandstone deposited during the Proterozoic. Modelling infers a correlation between strain and simple curvature; we use simple curvature to infer how structural position and strain control fracture attribute variations in a fold and thrust belt.In high curvature regions, such as forelimbs, fracture intensities are high and fractures are short and oriented parallel to fold hinges. In low curvature regions fractures have variable intensities and are longer. Fracture orientations in these regions are scattered and vary over short distances. These variations do not relate to strain; data suggests lithology may influence fracturing. The strain history of fold structures also influences fracturing; structures with longer deformation histories exhibit consistent fracture attributes due to moderate-high strain during folding, despite present day low curvature. This is in contrast to younger folds with similar curvatures but shorter deformation histories. We suggest in high strain regions fracturing is influenced by structural controls, whereas in low strain regions lithology becomes more important in influencing fracturing.