In the Western Mediterranean sea the contact between the Iberian and African plates has not a clear and delineated boundary. The diffuse contact area of ~400 km wide and ~1200 km long present a widespread deformation between the old continental margins. Several tectonic models have been proposed to explain the evolution of this plate boundary but more information about the crustal an mantle structure is needed to elucidate between those models. The main goal of this project -TRANSCORBE- is to study the Crustal and Mantle structure of the transition between the different domains that form the northern part of the Africa and Iberian plate boundary. We use receiver function techniques in a highly dense profile of broad band stations: ~120 km long with spacing of ~3 km between stations. The aim is to study the transition between the contact area of the Alboran domain and the stable continental region known as the Iberian Massif domain.