Automatic detection method of planar heterogeneities intersecting the stratification of an environment

The invention concerns a method for automatic detection of planar heterogeneities intersecting the stratification of an environment from images of a borehole wall or developed core samples of said environment, which consists in using an original image defined in a system of axes (X1, Y1, Z1) associated with the borehole whose axis is Z1, said image containing, for a zone, traversed by the bore hole planar heterogeneities consisting of stratification planes (2 to 14) and planar heterogeneities (15 to 23) intersecting the stratification planes. The invention is characterised in that it consists in: determining a dominant orientation of the stratification planes located in at least on part of said original image; filtering the original image to eliminate the planar heterogeneities of the stratification planes (2 to 14) located in the dominant direction; determining on said filtered image at least two contour segments (15' to 23') of the heterogeneities intersecting the stratification planar heterogeneities.