The aim of our study is to understand how the rifted margins are inverted and integrated in orogens during early inversion processes. In order to resolve this topic, we must describe the architecture of the former rifted margins. We looked the tectono-sedimentary record, deduced from the analysis of fault-sediment relationships and subsidence and thermal maturity of rift basin development, in order to unravelling the rifting processes. We used the Pyrenean range as study case, because a Cretaceous hyperextended rift system is preserved and integrated in this orogen.
Rifting event in Pyrenees is associated with a pre-rift decoupling layer (Upper Triassic evaporites) that play a significant role on the rift and orogen architecture. In the distal domain, along the main axis rift axis, the pre- and syn-rift sediments of the basin directly overlies exhumed mantle assisted by the efficiency of the decoupling layer. Associated with the thinning, the basin is also affected by a HT/LP metamorphism with maximum temperatures exceeded 500°C.