The emplacement mechanism and kinematics and the 3-D geometry of the Variscan granite pluton of Mortagne are interpreted, using systematic measurements of the granite structure allied with micro-structural observations, from a detailed gravimetric study. It is proposed that magma infilled a pull-apart structure which formed along a jog of a northwest-southeast–trending sinistral zone of shear. A second episode of shearing, under a dextral regime and independent of emplacement, was responsible for perigranitic tectonites. These successive transcurrent opposite movements, already documented for Variscan times in western France, are discussed concerning the age of the Mortagne pluton (313 ± 15 m.y.).

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