Correlations Between Natural Fracture Attributes and Equivalent Dual-Porosity Model

Thanks to advanced fracture analysis software, seismic, structural, logging and core information on fractured reservoirs can now be integrated into distribution laws of fracture attributes such as density, length and orientation. In addition, the stochastic network images derived from these distributions can be converted into an equivalent dual-porosity model using an efficient methodology and computation procedures described in recent publications. This paper gives the results of an extensive application of this conversion tool to establish correlations between the distribution parameters of fracture attributes and the equivalent fracture permeabilities of the equivalent dual-porosity model. Geometrical attributes controlling connectivity of the fracture network have been studied on 2D images of a single fracture set: average density, dispersion of azimuths, fracture lengths average and dispersion. Furthermore, the effect of fracture conductivity dispersion han been studied. Analytical relationships have been defined and abacuses constructed for easy use in field applications. The percolation threshold of the fracture network has also been quantified as a function of fracture distribution parameters.