Linking Gondwana inheritance to Alpine paleogeography in the Northern Dora-Maira Massif (Western Alps)

Inherited structures in rifted continental margins strongly influence the architecture and evolution of collisional orogens. The northern Dora-Maira Massif in the Western Alps (NW Italy) preserves records of such inheritances, capturing the transition from Gondwana inheritance to Alpine convergence. New lithostratigraphic and structural data, together with U-Pb zircon dating, reveal a long-lasting tectonostratigraphic and/or magmatic evolution during (i) pre-Permian, (ii) Permian, (iii) Triassic and (iv) Jurassic time intervals. The heterogeneous Paleozoic basement consists of pre-Variscan micaschist and metabasite, and was intruded by Permian igneous bodies now corresponding to the Borgone metagranite and Luserna augen gneiss. The basement was later overlain by a Mesozoic cover made up of Lower Triassic siliciclastic sediments, a Middle to Upper Triassic carbonate platform and Lower to Middle Jurassic syn-rift deposits linked to the opening of the Ligurian-Piedmont Ocean Basin. Our results highlight that the Dora-Maira Massif was located within a transitional paleogeographic domain, emphasizing the role of pre-rift architecture in governing margin segmentation. Successive cycles of sedimentation, magmatism, and rifting created structural and rheological heterogeneities that may have localized strain during the Cenozoic Alpine-related overprinting. The Dora-Maira case illustrates that deep-time inherited structures and tectonostratigraphic settings continue to influence rifting, subduction, and collision, offering a broader framework for understanding the dynamics of orogens worldwide.