Table 1 Schematic relationships between deformation and metamorphism in the lithologies studied (Roisan Zone and Arolla Series, Lower Unit)
Stage | Age | Structure | Unit | Metamorphic conditions |
|---|---|---|---|---|
D1 + M1 + MAGI | Pre-Alpine | Migmatitic structures and foliation | VALPELLINE SERIES | Granulite-Amphibolite |
Inequigranular aggregates | CUNEY and BECCA DI SALE’ SLICES | Amphibolite | ||
Igneous intrusion | AROLLA SERIES (coronitic domain) | |||
D2 + M2 | Pre-Alpine | Coronas | AROLLA SERIES (coronitic domain) | Greenschist |
D3 + M3 | Alpine | S3 | AROLLA SERIES (mylonitic and tectonitic domains) | Blueschist |
CUNEY and BECCA DI SALE’ SLICES | Blueschist | |||
ROISAN ZONE | Blueschist?-Greenschist | |||
D4 + M4 | Alpine | S4; F4, PA4 | AROLLA SERIES (mylonitic and tectonitic domains) | Blueschist |
CUNEY and BECCA DI SALE’ SLICES | Blueschist | |||
ROISAN ZONE | Blueschist?-Greenschist | |||
D5 ± M5 | Alpine | F5; PA5,S5 | AROLLA SERIES (mylonitic and tectonitic domains) | Greenschist |
ROISAN ZONE | ||||
D6 ± M6 | Alpine | Fractures and veins | All lithologies | Greenschist |