Over the last decades some main oil and gas discoveries have been achieved in the West Africa margin and the production is expected to rise in the next years, especially in deep and ultra-deep waters. The main trapping mechanism in the conjugated South Atlantic passive margins (but also in other salt provinces as Caspian basin, Gulf of Mexico, etc; see Fig. 1), is generally connected to salt tectonics. This paper, that arises from a larger thesis work, is carried out by a collaboration between the University of Trieste and Eni E&P Division: its first target is the interpretation of a set of seismic horizons, both in pre- and post-salt sequences, along some confidential depth migrated 2D seismic profiles of the W-Africa margin; a second target is balancing cross-sections to validate the interpretation and to promote a better understanding of the geological evolution of the halocinetic structures. The confidentiality of the data doesn’t allow us to detail the exact position of the profile, but many considerations and results could be regionally applied.