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Table 6 Representative analysis of main minerals of garnet-free gneiss (CR115)

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 Jd1 Jd2 Omp1 Aeg1 Wm1 Wm2 Ep1 Ep2 Bt1
SiO2 59.6 58.72 55.78 53.39 53.93 51.58 38.77 38.1 43.12
TiO2 0.04 0.09 0 0 0.04 0.07 0.04 0.03 0
Al2O3 24.73 18.77 10.63 1.46 25.48 27.44 25.59 25.67 19.6
FeOt 0.55 6.43 8.73 26.18 3.63 3.71 10.41 9.36 13.97
NiO 0 0 0 0 0 0 0 0 0
MnO 0 0.12 0.49 0.14 0.11 0.12 0.14 0.14 0.26
MgO 0.04 0.86 5 2.05 3.12 3.33 0 0.01 9.02
CaO 0.23 1.71 10.8 3.76 0 0 23.28 22.68 0.05
Na2O 14.98 14.2 8.65 12.56 0.04 0.04 0.01 0.01 0.24
K2O 0 0 0.06 0.01 11.19 11.32 0.06 0.02 9.99
Cr2O3 0.02 0.01 0 0 0 0 0.02 0 0
TOT 100.19 100.91 100.14 99.55 97.54 97.61 98.33 96.03 96.3
Si 2.01 2.01 1.99 1.97 3.53 3.39 3.02 3.03 3.1
AlIV 0 0 0.01 0.03 0.47 0.61 0 0 0.9
AlVI 0.98 0.76 0.44 0.03 1.5 1.52 2.35 2.4 0.76
Ti 0 0 0 0 0 0 0 0 0
Fe2+ 0.02 0.02 0.09 0 0.2 0.2 0.03 0.03 0.81
Fe3+ 0 0.17 0.17 0.81    0.65 0.59 0.03
Mg 0 0.04 0.27 0.11 0.3 0.33 0 0 0.97
Mn 0 0 0.01 0    0.01 0.01 0.02
Na 0.98 0.94 0.6 0.9 0 0 0 0 0.03
Ca 0.01 0.06 0.41 0.15 0 0 1.94 1.93 0
K 0 0 0 0 0.94 0.95 0.01 0 0.92
Cr 0 0 0 0 0 0 0 0 0
SUM 4 4 3.99 4 6.94 7 8.01 7.99 7.53