Quantitative Measurements of Fracture Aperture and Directional Roughness from Rock Cores

A general method to obtain objective measurements of fracture aperture and oriented roughness from rock core through the digitization of fractures is described. In this method, the true orientation of the borehole and line of maximum dip for the true discontinuity on a lower hemispherical projection is plotted. The ATOS system was used to digitize the core in the closed position and each half of the core individually. The time required to process the data for each fracture following acquisition depends on the selected measurement resolution and raw data file sizes. This method provides a permanent digital record of the fracture that could be assessed quantitatively or qualitatively at any time in the future. It also provides physical limits for coupled hydro-mechanical modeling of flow in rock fractures and shows that irregular and anisotropic surface topography can lead to complex recirculation patterns and flow channeling.