Comprehension oi the fluid flows in fractured reservoirs is based on the study of the parameters which determined the geometry of the fracture network. The in situ stresses which determine the direction of the flows are oi the utmost importance. In situ stresses cannot be appreciated by direct measurements but there are indirect methods: interpretation of borehole breakouts, hydraulic fracturing,... The point is that all these indirect methods can on y yield a local evaluation of the stress pattern which is likely to differ on a field scale. It is therefore important to use models that are able to provide an overall comprehension of the stress pattern(s) in the reservoir. For example, analogical models using paraffin as a material to study deformations make it possible to study the deviation of the major horizontal stress by simple or complex faults. Experimental results are confirmed by studying similar phenomena on real scale. This type of analogical modelling is then used to determine the function of the Various geological features in the gas field of Meillon - Saint-Faust (France). The preferential use of some fractures, highlighted through experiments, is supported by the drainage pattern of the field and the water breakthrough history in the studied sector of the field.