Geostatistical analysis of surface morphology and its relationship with hydro-mechanical properties of natural fractures

Abstract

The morphological properties of rock fractures are intimately linked with its hydro-mechanical behaviours. In this paper, the relationship between the two properties for a real rock like fracture is studied using geostatistical analysis techniques. Surface morphology of the fracture is modelled through variograms for different directions to determine the anisotropy extent of the fracture’s roughness. The results are then compared to the results of a fluid flow simulation undertaken for a separate study to determine whether any correlation exists between the two properties. Observations suggest a clear correlation between directional dependence of the asperity elevations of a fracture surface and fluid pressure drop. Thus, geostatistical modelling of surface morphology can potentially be used to predict and understand the hydro-mechanical properties of a fracture which can prove to be valuable in real applications such as minimising the negative impacts of fractures to hydrocarbon production.