A. The N-S seismic profile (location Figs. 4 and 11) with better penetration, running close to OR-1, discovered below the SGS marine sediments a thick (3 to 4 km) section of syn-tectonic sediments. They could be continental Late Eocene to Late Chattian in age following field studies and comparison with similar basins in southern France (Séranne et al., 2021; Semmani et al., 2023; 2024) (See Sect. 6 Discussion). They were deposited in a narrow half graben (20-30 km wide) bounded westward by the Capo Frasca-Sinis Fault (not crossed by the profile). Above, the strong reflectors at the Base of the Miocene are interpreted as turbidites at the toe of prograding deltas fans (See Fig. 12B) in a deep marine basin resulting from the rifting of Sardinia (SGS). B. Enlargement of the southern part of profile Figure 12A (dotted rectangle on Fig. 12A), stratigraphically calibrated at OR-1. It shows a detail of superimposed deltaic fans prograding from the South, infilling the deep marine Late Chattian Aquitanian to Lower Burdigalian basin of the SGS, with transition to shales and clastics turbidites identified in OR-1. The sediments above the green horizon, Upper Burdigalian to MES in age, onlap the prograding fans and are post-rift sediments.