1. Process for three-dimensional modeling of a geological volume, in which cells are defined that are adapted to the critical surfaces of the geological volume to be modeled, characterized by the fact that the process comprises the following steps: a) defining an assembly of polyhedral macrocells in the geological domain adapted to the geometry of the geological layers of the volume to be modeled; b) carrying out a parametering of the geological space to match the geological domain studied and a parametric domain, by associating with a point belonging to the geometric domain an image point located in the parametric domain; c) defining a virtual subdivision of said macrocells into microcells, whose geometry is obtained by subdivision of the geometry of each macrocell, such that the positions of each microcell will be deduced by interpolation of the positions of the summits of the corresponding macrocell and such that microcells correspond to nodes of a regular grill covering the parametric domain; so as to model a function representative of a geological property on the regular grill of the parametric domain by reducing the number of data to be memorized.