PALEOMAGNETIC EVIDENCE FOR LATE MIOCENE ROTATION OF THE SWISS-ALPS - RESULTS FROM THE NORTH ALPINE FORELAND BASIN

Magnetostratigraphic studies in the Oligocene to Miocene north Alpine foreland basin of Switzerland suggest a post-middle Miocene (< 13 Ma) clockwise rotation of the Swiss Alps, The angle of rotation is 16-17 d egrees with respect to the present-day earth's magnetic field. This ro tation can be observed in 12 sections analysed for palaeomagnetic dire ctions which cover a lateral distance of approximate to 250 km (SW-NE extension), The rotation angle shows neither a significant change thro ughout the examined period of deposition, nor is it dependent on the t ectonic position of the individual regions in the basin (autochthonous or allochthonous Molasse).