This diploma thesis focused on tectonic* and metamorphism* of the Alpe Larecc (Val Lavizzara, North of Ticino, Switzerland) around the main Lareccio anticline* (= Verzasca anticline), at the limit between pre-Mesozoic* metasediments* of the Campo Tencia unit and the Verzasca gneiss* complex on Simano nappe.

Metasediments are mainly micaschists* (figure on the left) and paragneiss*. Besides both micas (biotite and muscovite), plagioclase (5-25% anorthite) and quartz (ubiquist in those lithologies), garnet, kyanite and staurolite are also often associated. In some particular lithologies*, garnet and/or staurolite can form centimetric porphyroblasts*. The metasediment layers with porphyroblasts are irregular from millimeter- to decameter-size thickness. The sediment are composed of an alternation of argilous (micas-rich) and detritics (rich in quartzo-feldspathic material) deposits.

Amphibolites* (in its broad sens, figure on the right) are composed of alternation of massive amphibolites (in the strict sens with often more than 75% amphibole) and paragneiss with amphibole (right figure). The amphibolite (strict sens) shows a mineral assemblage* with green hornblend (tschermakite), garnet, plagioclase (15-45% anorthite) and biotite. The local retromorphosis* of those rocks lead to the formation of epidote-calcite-chlorite assemblage.