Fig. 7
Field aspect and petrographic characterization of the Granero Orthogneiss. a An outcrop displaying the characteristic, regular and tabular, foliation in the orthogneiss, indicating strong flattening during ductile deformation (44° 55′ 26.31′′ N, 7° 06′ 49.9′′ E). b A folded quartzo-feldspathic layer in the augen orthogneiss, interpreted as a former aplitic dyke. Note that an early foliation, parallel to the boundaries of the meta-aplitic dyke, is observed in the orthogneiss. The asymmetry of the folds is consistent with a top to the W sense of shear (44° 54′ 51.77′′ N, 7° 10′ 02.46′′ E). c A section perpendicular to the foliation and parallel to the stretching lineation evidences the strong flattening of the orthogneiss body. Note that narrow shear bands (C’) indicate top to W sense of shear (44° 54′ 55.8′′ N, 7° 10′ 05.4′′ E). d Cross-polarised light photomicrograph of the Granero orthogneiss (sample OG34, 44° 57′ 27.1′′ N–7° 08′ 11.3′′ E) showing a millimetre-size alkali feldspar with a simple twin and exsolution lamellae (perthite)