Geology of Pletovarje motorway tunnel (Slovenia)

Abstract

Styrian motorway crosses the Pletovarje ridge through the tunnel having the same name. It intersects the most eastern extension of the Southern Karavanke tectonic unit. Considering geological conditions, the tunnel could be divided into three sections: the inner Donat / Donačka fault zone composed of tectonic lenses of different lithostratigraphic units (of paleozoic, triassic and tertiary age), massive dolomite (lower triassic) and Smrekovec series of oligocene age. Main faults have east - west direction and are subvertical.