In the central cliffs of Murração beach can be observed dark shales and siltstones from the Bordalete Formation (345 million years) under the limestones of the Murração Formation (328 million years), separated by a fault along which tectonic movement occurred that put the limestones over the shales and siltstones. Both formations contain fossil associations characteristic of the Lower Carboniferous Period (318 to 359 million years ago). In those cliffs we can also observe basic veins, testimonies of the early episodes of the opening of the Atlantic Ocean (200 million years ago).