Truncation diagram determination for a pluri-Gaussian estimation

The present invention relates to a method for determining a truncation diagram for a pluri-Gaussin geological parameter estimation associated with a zone of a real subsoil. The method comprises receiving an auxiliary variable describing the zone, computing a normalized variable based on the auxiliary variable and determining a weighted probability map for the normalized variable, each point of the weighted probability map being in correspondence with a point, of the truncation diagram. Moreover for each point of the truncation diagram, the method further comprises determining an associated geological parameter based on the probability value of each point of the weighted probability map. The method is also used to adapt truncation diagram to global or local target, proportions of the facies model to built.