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Table 1 Summary of deformation-metamorphic transformation stages with characteristic structures and mineral associations

From: Blueschist mylonitic zones accommodating syn-subduction exhumation of deeply buried continental crust: the example of the Rocca Canavese Thrust Sheets Unit (Sesia–Lanzo Zone, Italian Western Alps)

Stage Event Structures Mineral association
Grt-bearing gneiss
 I pre-1a Coronitic Wm1 + Grt1a + Qz
pre-1b Microfractures Grt1b
 II M1, D1 S1 discontinuous foliation Wm2 + Grt2 + Jd1 + Qz + Ep1 ± Ttn1
 III M2, D2 S2 mylonitic foliation Wm3 + Grt3 + Gln1 + Qz + Pl1 + Ep2 ± Ttn2
 IV M3, D3 AP3 folding Cpx1
Grt-free gneiss
 I pre-1 Coronitic Qz + Bt1
 II M1 Coronitic Wm1 + Jd1 + Cpx1 + Qz + Ep1 ± Ttn1
 III M2, D2 S2 mylonitic foliation Wm2 + Jd2 + Ep2 + Qz ± Ttn2 ± Gln1
 IV M3, D3 AP3 folding Cpx2 + Qz + Pl1
Orthogneiss
 I pre-1 Coronitic Kfs1 + Qz
 II M1 Coronitic Wm1 + Grt1 + Jd1 + Qz ± Ttn1
 III M2, D2 S2 mylonitic foliation Wm2 + Jd2 + Qz ± Ttn2
 IV M3, D3 AP3 folding Cpx1