Paleomagnetism of external southern and central Dinarides and northern Albanides: Implications for the Cenozoic activity of the Scutari-Pec transverse zone

International audiencePaleomagnetic investigations have been conducted on 43 Cretaceous to Miocene sites (500 oriented cores) from the southern and central external Dinarides and from the northern external Albanides. The 24 reliable sites (out of 33) from the Dinarides do not document any significant rotation with respect to Africa since at least early Eocene. This result contrasts with the very coherent post-Eocene 45 ø clockwise rotation previously observed in the external Albano-Hellenides from Peloponesus to the Tirana basin. These new results suggest that the Scutari-Pec line, located between the two orogens and considered as a Mesozoic transform fault on the basis of geological observations, is the place where the torsion between the Dinarides and the Albanides recently occurred. On a local scale, four sites (out of 10) from two ridges located in northern Albania, south of the Scutari-Pec line but with a Dinaric trend, show that these two structures have undergone a •-30 ø post-Eocene clockwise rotation. This intermediate value of rotation between the north and the south suggests that the Scutari-Pec line is, in fact, a rather wide transversal zone in which the two ridges are located. It acted as a decoupling zone between the Dinarides and the Albano-Hellenides during the Cenozoic and probably until the Pleistocene time. The strong seismic activity recorded in this region and the anomalously high positive heat flow (documented by other authors) are also evidence for the recent activity of the Scutari-Pec transverse zone