A Geomechanical Approach to Predicting Fracture Behaviour - An Example from the Gorm field, Danish North Sea

The Gorm field, Danish North Sea, is central to the pipeline infrastructure of the region. Declining production is strongly dependent on fracture permeability. Geomechanical modelling (Elastic Dislocation) can be used to predict first order fracture orientations and density in the chalk reservoir. We can resolve in situ stresses onto fractures in order to model their hydraulic conductivity by estimating how close they are to failure. Both of these predictive techniques yield good agreement with well data. The inference is that if we can predict (reasonably) the orientation of a fracture in a given area and apply the stress field of that area to it, we can determine whether it will be optimally oriented for flow. This coupled with the density of those fractures is a powerful tool in identifying potential targets for production tests, orientation of line drive patterns and inputs for reservoir management. At the time of writing a new well targeted one of our predicted “sweet spots”, becoming the most productive well in the field accounting for over 25% of daily production, suggesting that mature (and even virgin or developing) fields could benefit from a better understanding of the structure, both at the seismic and sub-seismic scale.