The interpretation of seismic facies in the molassic deposition of Preadriatic Foredeep

Résumé

The purpose of this article is to illustrate the principles of seismic facie analysis used in the interpretation of sedimentary rocks, in siliciclastic deposits, especially in molassic one. The recognition and definition of a seismic facies and the analysis of its vertical evolution (facies associations) lead to an environmental interpretation, which can give useful information on both sedimentary facies and reservoir characteristics. With this aim, the major depositional systems, from continental to deep marine, and the depositional elements in which they can be subdivided, will be briefly overviewed in terms of extension, geometry, continuity and lateral variations. For each of these systems, it is pointed out, the major physical active processes during the deposition, the resulting sedimentary structures and their vertical and lateral evolution. The comparison between the environmental interpretation derived from bottom cores, well - logs and that derived from the current depositional models, is used to predict the nature and distribution of reservoir and sealing rocks.