Ofioliti, 2019, 44 (2), 97-110 - doi: 10.4454/ofioliti.v44i2.527 97 MAPPING THE PROGRESSIVE GEOLOGIC HISTORY AT THE JUNCTION OF THE ALPINE MOUNTAIN BELT AND THE WESTERN MEDITERRANEAN OCEAN Guido Gosso*, Jean-Marc Lardeaux**, °, Davide Zanoni*, , Silvia Volante***, Michel Corsini**, Riccardo Bersezio*, Jean Mascle°°, Luca Spaggiari*,°°°, Maria Iole Spalla*, Michele Zucali*, Gérard Giannerini**, and Laurent Camera** * Dipartimento di Scienze della Terra “A. Desio”, Università degli Studi di Milano, Italy. ** UMR 7329, Géoazur, Université Nice Sophia-Antipolis, Valbonne, France. *** Earth-Dynamics Research Group, ARC Centre of Excellence for Core to Crust Fluid Systems (CCFS) and The Institute for Geoscience Research (TIGeR), School of Earth and Planetary Sciences, Curtin University, Australia. ° Center for Lithospheric Research, Czech Geological Survey, Praha, Czech Republic. °° UMS 829, Observatoire Océanologique de Villefranche, Villefranche sur Mer, France. °°° Present address, since July 2015: ENI Spa, Upstream and Technical Services, San Donato Milanese, Italy. Corresponding author, e-mail:
[email protected] Keywords: geological event map; polycyclic orogeny; incremental tectonic history; Variscan orogeny; Alpine orogeny; Apennine subduction; Ligurian-Provençal margin; western Mediterranean. ABSTRACT This contribution illustrates a new type of map, the “geological event map” (1:250,000 scale), which highlights the progressive steps of the geologic his- tory recorded in the polycyclic orogenic belt of the European Alps, at their southwestern termination facing the western Mediterranean Sea. The formula of historical progression simplifies comprehension of significant phenomenal visions and reorients public curiosity towards geologic processes. This part of the Alpine belt records a geologic history starting with the Variscan convergence during Devonian, throughout the opening of the Tethys Ocean, Alpine conver- gence, followed by Apennine subduction driving the opening of the Ligurian-Provençal Ocean.