1. A method of 3D object delineation from 3D seismic data comprising the steps of: a) providing 3D seismic data; b) processing the data based on a first characteristic, wherein said first characteristic is extracted from the data and compared with at least one reference characteristic so as to define a set of object data; c) delineating the object data according to a first delineation technique; d) transforming the delineated object data using a second delineation technique so as to obtain a set of improved object data; e) extracting object data from the improved object data set; f) and repeating steps b) to e) using the extracted object data, until desired criteria are reached, so as to define a region of interest; and g) wherein the first delineation technique includes active contour delineation; and the second delineation technique includes level set segmentation; the region of interest being defined is a geological element.