The use of terrestrial laser scanning in quantifying fault and fracture attributes in reservoir outcrop analogues

Fluid flow in hydrocarbon reservoirs is influenced by the geometry, spatial distribution and hydraulic properties of faults and fractures. The resolution of seismic reflection data is such that whilst major faults (throws > 20 m) can be mapped in three dimensions, there is little information on the 3D geometries of small-scale (sub-seismic) faults. The Fractured Reservoirs 3D Digital Atlas (FR3DA) project has begun to address this issue by using new terrestrial laser-scanning and digital surveying techniques to construct geospatially referenced 3D structural models from rock outcrops containing sub-seismic fault and fracture networks in a range of tectonic and sedimentological environments. FR3DA datasets include: deformation bands in porous sandstones adjacent to seismic-scale normal and thrust faults; slip surface and damage zone architecture in carbonates and siliciclastics; fault zone geometry and fault rock distribution within siliciclastic coal measure sequences; sub-seismic normal faults and relays in sandstone-shale interbeds; and fracture density and distribution within folded carbonates. Fault and fracture attributes such as spatial distribution, density and connectivity have been derived from each structural model to allow comparison of fault zones architectures and fracture attributes between the different reservoir analogues. These attributes provide a unique quantitative geospatial characterisation of sub-seismic scale structures in a range of tectonic and sedimentological settings.