GNGTS 2023 - Atti del 41° Convegno Nazionale

Session 1.1 - POSTER GNGTS 2023 The Kruja thrust front is composed by an outcropping internal roof thrust and a basal thrust envelopping a stack of thrusts buried under the Tirana wedge-top basin deposits, deformed at surface by the NW-SE oriented Makaresh, Fushë-Kruja and Ishëm anticlines. The main thrust (Dajti-Kruja) bounds with a NW-trending rectilinear front the Dajti mountain ridge for ca. 50 km (Fig. 2, 3a). The very steep and straight scarp just above the tectonic contact of the Mesozoic limestones with the underlying Oligocene flysch deposits is suggestive of neotectonic activity, but the slope deposits were not seen affected. In the frontal zone, Quaternary slope breccias were found in tectonic contact with the limestones through a SW dipping normal fault (Fig. 3b) NW of Kruja, without a clear scarp at surface, likely representing secondary phenomena within the thrust mechanisms. Conversely, the morphological connection between the emergence of the thrust and the top surface of old Quaternary breccias, now largely eroded, under the old castle, may suggest sealing (Fig. 3c). Overall, the data collected so far are insufficient to conclusively deny the current activity of the thrust, constraining it to the younger structures west of it.