Quantitative structural analysis of reservoir outcrop analogues

The speed and efficiency of data acquisition with terrestrial laser scanning and dGPS, and the level of detail and spatial precision provided by these methods, means that quantitative 3D structural analysis is now able to yield results that were previously impossible or impractical to obtain. We will present a range of case studies that illustrate the application of digital outcrop analysis techniques to structural studies of reservoir analogues. These include detailed spatial analysis of complex fracture networks, quantification of 3D fold geometries, and examples of fractured folds that have shed new light on the inter-relationship between fold curvature and fracture density.

Various fracture attributes can be quantified from the virtual outcrop data, including 3D curvature, fracture connectivity, branch-line geometry, detailed fault throw profiles, and the spatial correlation between fault corrugations and splays. Measurement of such fracture parameters, collected from a range of outcrop analogues, provides direct quantitative input for calibration of geomechanical models, and for comparison with fracture networks seen in subsurface data or derived from deterministic or stochastic methods.

A number of key issues remain for future research and development. These include: improved interactive tools for construction and interpretation of digital outcrop analogues; better methods of interpolation and extrapolation of surfaces in 3D; more advanced 3D spatial statistics; quantification of uncertainty associated with construction and interpretation of digital outcrop models; increased sophistication of reservoir modelling software to incorporate more realistic structural geometries; decrease in cost and weight of digital field equipment, and many others.