Data collecting and mapping and for kinematic reconstruction: a case history from the Ligurian Alps.

Four superposed tectonic units crop out in the area considered. Detailed mapping and data on stratigraphy, tectonics and metamorphism were used to reconstruct the complex Alpine structural geometry and possible strain path. Using all available structural data (attitude of foliations, hinge lines, stretching lineation; finite strain measurements), a retro-deformation process was applied in order to reconstruct the most probable configuration and evolution of the top of the pre-Namurian basement during Late Carboniferous times. Local data and related processing have been inserted into a wider regional framework, characterised by the stacking of a great number of nappes. Starting from the most probable Late Jurassic palaeogeographic setting for this sector of the Alpine chain, the authors have produced a general model of the kinematic evolution of the Briançonnais units, in which a satisfactory fit is found for the characteristics of the nappes considered here.