Pre-Alpine Tectono-Stratigraphic Reconstruction of the Jurassic Tethys in the High-Pressure Internal Piedmont Zone (Stura di Viù Valley, Western Alps)

We present a detailed description of the tectono-stratigraphic architecture eclogite-facies Internal Piedmont Zone (IPZ) metaophiolite, exposed in Lanzo Valleys (Western Alps), which represents remnant Jurassic Alpine Tethys. Seafloor spreading and mantle exhumation processes related to Tethys evolution strongly conditioned intra-oceanic depositional setting, resulted an articulated physiography heterogeneous stratigraphic succession above exhumed serpentinized mantle. “Complete” “reduced” successions were recognized, reflecting deposition morphological or structural lows highs, respectively. The “complete” consists quartzite, followed by marble calcschist. differs for unconformable contact calcschist directly rocks, lacking quartzite gray marble. serpentinite at base this is intruded metagabbro characterized its top ophicalcite horizons. Mafic metabreccia grading metasandstone mark transition between successions. character reconstructed basin floor IPZ metaophiolite well comparable with Middle Jurassic–Late Cretaceous both Queyras Complex (External Zone) Ligurian Units (Northern Apennines) modern slow-spreading mid-ocean ridges.