FIG. 1. — Geologic sketch map of the Tertiary Piedmont Basin, Monferrato Complex and Torino Hill, with the location of Stazzano site («) (modified from Gelati & Gnaccolini 1996): 1, Pliocene to Recent deposits; 2, Messinian deposits; 3, Langhian to Tortonian shelf to slope deposits; 4, Upper Burdigalian to Tortonian mainly turbiditic succession; 5, Upper Oligocene to Burdigalian turbidite systems and hemipelagic mudstones; 6, Upper Eocene to Lower Oligocene deposits: a, alluvial to coastal conglomerates, shallow marine sand- stones and hemipelagic mudstone; b, slope and base-of-slope, resedimented conglomerates; c, mainly turbidites; 7, Upper Eocene to Tortonian siliciclastic deposits of the NW Apennines – Basso Monferrato – Torino Hill wedge; 8, Alpine and Appenninic allochthonous units; 9, depocentre axis of the Plio-Quaternary basins; 10, buried thrust-front of the Torino Hill – Basso Monferrato – NW Apennines wedge; 11, buried south-vergent backthrusts of Basso Monferrato, active from Messinian onward; 12, buried, pre-Burdigalian back- thrusts of Western Alps; 13, tectonic lines. Abbreviations: SV, Sestri-Voltaggio Line; VV, Villarvernia-Varzi Line.