EVALUATION OF A DISCRETE FRACTURE NETWORK (DFN) MODEL AND COMPARISON WITH FRACTURED CARBONATE OUTCROPS, MONTE CONERO, ITALY

Characterization of fracture geometry and distribution is important for understanding fluid flow in fractured reservoirs and aquifers with applications in hydrology, petroleum- and mining engineering, storage of CO2 and the use of geothermal energy. Because it is impossible to characterize every single fracture, modelling of fracture networks with Discrete Fracture Network (DFN) models (Jing, 2003) may be used, combining stochastic modelling, Monte Carlo simulations and fracture properties measured for example on outcrops of rocks (e.g. Massart et al., 2010). FracSim3D, elaborated by Xu & Dowd (2010), is one of the available programs which offers representations in two and three dimensions and statistical tools for the analysis of the results. The aim of this study is to compare the results of DFN modelling using FracSim3D with a map of a fractured carbonate outcrop. This evaluation is made in terms of the geometrical, mechanical and hydraulic properties of fractures, such as, length, connectivity, orientation, position and structural typology, in order to define the accuracy of the model for a fluid flow analysis. The use of Geographic Information System (GIS), Excel macro-script and field-work data, was combined to create the input for FracSim3D. Fracture properties including orientation, length, opening and fracture type, were measured during field work on exposures of Mesozoic fractured carbonate outcrops near Monte Conero (Le Marche Region, Italy). In this sense Monte Conero serves as an analogue for a fractured carbonate aquifer or reservoir.