Tectonic Structures Along the Periadriatic Lineament in Slovenia

The Periadriatic lineament extends from the Sesia zone in Italy across southern Austria into Slovenia, in the area of the Karavanke mountains. It continues eastwards into the Pannonian basin in Hungary as the Balaton line. The Karavanke mountain range runs from Slovenia in the east westwards into the Carnian Alps of Austria. Further east they extend beneath the Tertiary sediments of the Pannonian basin into Hungary. The Karavanke mountains represent a boundary zone between the Eastern Alps to the north and the Julian and Savinja-Kamnik Alps or Southern Alps to the south. The Periadriatic lineament intersects the eastern part of the Karavanke mountains from Austria, trending eastwards, dividing this unit into the Northern and Southern Karavanke. Geologically, the Karavanke mountains consist of Palaeozoic, Mesozoic (mostly Triassic) rocks and Tertiary sediments. In the eastern part of the Karavanke mountains, along the Periadriatic lineament, there is a belt of magmatic rocks, granite in the north and tonalite in the south, with a narrow belt of metamorphic rocks in between. The tectonic structure of the aforementioned boundary zone is especially interesting. New research results show that both the overall structure and individual tectonic units respectively of this zone steeply deep towards the south beneath the Julian and Savinja (Kamnik) Alps. The Karavanke mountains are on the north thrusted over Eastern Alps by horizontal movements along single faults. Among these faults, the Periadriatic lineament, along which the mentioned magmatic (granite - tonalite) zone appears, is especially interesting. This paper attempts to define the sequence of tectonic movements which took place at the end of the Alpine geotectonic cycle, and the tectonic structure of the Karavanke Mt. zone.