Method for automatically forming a model simulating the stratigraphic structure of an underground zone

Abstract

A method for automatic modelling of the stratigraphic structure of an underground zone with fast adjustment of the parameters of the model with observed or measured data is disclosed. The method comprises a) determining, by measurement or observation, a series of quantities (such as sedimentary deposit heights for example) representative of the stratigraphic structure of the zone at various points, b) implementing a (for example diffusive type) direct initial model depending on a set of parameters representative of the geologic formation process of the zone, c) determining, by means of the initial model, the values taken by the quantities at the various measurement or observation points, d) calculating, by means of the direct model, the gradients (by the analytic or finite-difference type method according to circumstances) of each quantity in relation to the parameters to be adjusted, and e) optimizing the model by minimizing by successive iterations the criterion function (preferably according to a quasi-Newtonian algorithm) until a sufficient difference reduction is obtained, by calculating the sensitivity of the direct model to the parameters to be adjusted, so as to produce a stratigraphic representation of the underground zone.

Dependencies are inferred from the claim text.