Schematic illustration for the application of the geological event concept for lithostratigraphy and sequenciel stratigraphy. (A) schematic geologic (lithostratigraphic) map, with cross-section (X/Y/Z) and schematic log from points X and Z, with three principal Formation (Fm A, Fm C, Fm B) and their respective members. Lithostratigraphic boundaries are represented by facies limits corresponding to a certain deposit environment along a transect as illustrate in (C). (B) the same map and cross-section from (A) are analysed and interpreted in term of depositional sequence to represent the different key surface (MFS/ES or SB) and the regressive and transgressive system tracks. These geological features are characteristic of depositional sequences event linked to the deposit of the different formation represented in (A). These two kind of geological event (deposit of the formations and the genetic sequences which are link to them) are registred in the Event Referential System in (D), allowing to proposed a complete sequence of event associated to different process (tectonic, deposit, etc.), to draw the geological history of the syn-divergence phase 1.