A method of 3D object delineation from 3D seismic data comprising the steps of, providing 3D seismic data; processing the data based on at least one characteristic whereby said characteristic is extracted from the data and compared with at least one reference characteristic and delineated based on the comparison, and defining a geological element based on the delineation. The characteristics may be adjusted. Data can be processed based on one characteristic then processed based on a second characteristic or data is processed based on two characteristics substantially simultaneously. Data may be processed n times producing n delineations from which the geological element is defined. An algorithm is provided for processing the data which may shift an evolving shape description of an object between explicit and implicit representations, where each shift applies a transformation to the object. Multiple sources of data may be utilized simultaneously to drive the delineation process.