Geology of the Monte Banchetta – Punta Rognosa area (Troncea valley, Western Alps)

Abstract

The map ‘Geology of the Monte Banchetta – Punta Rognosa area (Troncea valley, Western Alps)’ details the lithostratigraphy and structural setting of a key sector in the Alpine chain, characterized by close associations of continental and oceanic basements, and meta-sediments. The mapped Monte Banchetta – Punta Rognosa unit (BRU), tectonically juxtaposed to different metaophiolitic units, comprises the Punta Rognosa succession, made of serpentinized mantle overlain by Middle-Upper? Jurassic polymictic meta-breccia, with oceanic and continental clasts, and metasandstone, and the Monte Banchetta succession, consisting of continental crust and Lower–Upper? Jurassic carbonate-bearing quartzite, micaschist and polymictic meta-breccia. These two successions share the uppermost stratigraphic levels consisting of post-rift Upper Jurassic-Cretaceous carbonate-micaschists. The deciphered stratigraphic architecture indicates that the lower succession of the BRU represents portions of continental crust and exhumed mantle reworked and emplaced before deposition of post-rift sediments.

Keywords

• geological map
• lithostratigraphy
• monte banchetta-punta rognosa
• western alps