Transition from subduction to collision recorded in the Pan-African arc complexes (Mali to Ghana)

•The suture zone of the Dahomeyide belt, exposed coronitic HP granulitic massifs.•The closure of Pharusian ocean occurred along intra-oceanic arc and active margin from 800 to 600 Ma.•Between 620 and 610 Ma, the forearc system and the tip of the active continental margin were buried synchronously.•The positive Bouguer anomaly East of the suture zone, could correspond to the underplated buried forearc.•The transition from continental subduction to continental collision occurred between 610 and 580 Ma.