Subvertical fracturing is a common feature of carbonate reservoirs. Fracturing occurs on the local scale due to variable stress, differential compaction and chemical weakening of the rock. Larger-scale features occur due to deformation associated with folds or faults. Such fracturing can impact significantly on inter-well flows if the fractures form a connected network. A stochastic discrete fracture network (DFN) approach can be used to assess the geometry, magnitude and volume of fracture connectivity around wells. Such models make use of data from image logs, core logs, formation microscanner, production logs and outcrop maps.