Un nouveau point de départ pour l'histoire de l'Atlantique central

Abstract

The first oceanic crust in the central Atlantic is usually thought to have a Middle Jurassic age. The new interpretation of the two key parameters, the African homologue of the East Coast Magnetic Anomaly and the situation of the Triassic salt basin of Morocco and Novia Scotia, shows that this age was underestimated by about 20 Ma. In our kinematic reconstruction, the first oceanic crust begins at the Late Sinemurian. This difference in age is crucial for the evolution of those margins and we discuss here its consequences.