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Table 5 Representative analysis of main minerals of garnet-bearing gneiss (ZR4)

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)

Mineral Grt1a Grt1b Grt2 Grt3 Wm1 Wm2 Wm3 Jd1 Ep1 Ep2 Gln1 Ttn1
SiO2 37.98 37.47 38.14 38.2 45.61 52.48 50.33 58.68 37.38 38.14 56.6 30.7
TiO2 0.01 0.06 0.15 0.17 0.39 0.07 0.07 0 0.24 0.06 0.01 38.33
Al2O3 21.24 20.82 21.19 20.99 35.88 24.83 27.84 22.88 25.81 27.92 11.17 2.5
FeOt 34 35.88 25.37 19.52 1.03 3.46 3.73 1.63 9.43 6.85 17.37 0.48
NiO 0 0 0 0 0 0 0 0 0.01 0 0 0
MnO 3.23 4.94 1.66 3.36 0 0 0.07 0.01 0.13 0.06 0.1 0
MgO 4.12 0.84 0.54 0.21 0.56 2.47 2.94 0.34 0.16 0 5.25 0.01
CaO 1.04 1.94 13.99 17.48 0.01 0.07 0.04 0.66 23.2 23.17 0.29 28.03
Na2O 0 0 0.02 0.01 0.37 0.48 0.2 15.37 0.02 0 7.28 0.03
K2O 0.03 0 0.02 0.07 9.47 10.3 10.61 0.01 0.01 0.08 0.03 0.12
Cr2O3 0.04 0 0.01 0 0.02 0 0 0 0.03 0 0 0.05
TOT 101.69 101.95 101.09 100.02 93.35 94.16 95.83 99.57 96.41 96.27 98.1 100.26
Si 2.99 3.01 3 3.01 3.07 3.55 3.36 1.99 2.96 3 7.99 4
AlIV 0.01 0 0 0 0.93 0.45 0.64 0.01 0.04 0 0.01 0.38
AlVI 1.97 1.97 1.96 1.95 1.92 1.53 1.56 0.9 2.36 2.58 1.85  
Ti 0 0 0.01 0.01 0.02 0 0 0 0.01 0 0 3.76
Fe2+ 2.21 2.39 1.64 1.25 0.06 0.2 0.21 0 0 0.04 2  
Fe3+ 0.03 0.02 0.03 0.04     0.05 0.62 0.41 0.05 0.05
Mg 0.48 0.1 0.06 0.03 0.06 0.25 0.29 0.02 0.02 0 1.1 0
Mn 0.22 0.34 0.11 0.22     0 0.01 0 0.01  
Na 0 0 0 0 0.05 0.06 0.03 1.01 0 0 1.94 0.01
Ca 0.09 0.17 1.18 1.48 0 0.01 0 0.02 1.97 1.95 0.04 3.91
K 0 0 0 0.01 0.81 0.89 0.9 0 0 0.01 0.01 0.02
Cr 0 0 0 0 0 0 0 0 0 0 0 0
SUM 8 8 7.99 8 6.92 6.94 6.99 4 7.99 7.99 15 12.13