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Transcripción del abstract original del autor: The natural fracturing of rocks can play an important role in the improvement of permeability and may contribute to improve productivity in fields where the primary physical characteristics are poor. In the Algerian sedimentary basins, principally the south-western basins, determining the fractures network has always been the concern of geologists and the role of fracturing has been highlighted in several prospects. In the Ahnet basin, the production of gas seems to be unrelated to lithological variations in the reservoirs. In these large anticline structures, the presence of gas has been proven in the Cambro Ordovician reservoir, but only a few production wells have been moderately successful. This inconsistency is particularly due to the spatial distribution of fractures throughout the reservoir. In order to investigate different hypotheses, we used several approaches to solve the problems highlighted by the interpreter: essentially understanding the deformation process, prediction of fractured zones and building a discrete model of the fracture network. This approach combines several methods, including sand box modelling, numerical modelling, and statistical rules, for extrapolating observations from seismic and well data (fractal behaviour of faults families). The sand box and numerical tools analysis have allowed to answer to the questions related to the formation of these large anticlines and suggest a probable origin of the variation in the spatial distribution of the fractures. The statistical modelling is used to carry out analysis of the spatial variation of mean fracture attributes at the global scale (a few kilometers) and a 3D stochastic modelling of the fracture system at the local scale (a few ten of meters).