Structural and geomorphological map of the Passo San Marco–Pizzo di Trona area (Western Orobic Alps, Southern Alps, Italy)

We present a structural and geomorphological map of the Passo San Marco-Pizzo di Trona area (Northwestern Orobic Alps). This area was studied in order to make a contribution to the mapping and interpretation of the landforms and the mesoscale structures in the basement and sedimentary cover. The aim of this study is to provide a useful insight for a better understanding of the geological and geomorphological evolution of the Orobic belt during the Alpine orogenesis. The original geological survey was carried out at a 1: 5000 scale while the presented map is at a 1: 8000 scale. In particular, a detailed structural survey of brittle and ductile structures was carried out. The structural analysis has led to the identification of six phases of deformation: three pre-Alpine and three Alpine. During these deformation phases, ductile (folds and foliations) and brittle (faults, cataclasites and pseudotachylites) structures developed both in the Variscan basement and in the Permo-Triassic sedimentary cover.