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)

Swiss Journal of Geosciences

Table 7 Representative analysis of main minerals of orthogneiss (ZR19)

Mineral	Jd1	Jd2	Wm1	Wm2	Grt1	Kfs1
SiO₂	59.36	57.64	53.44	51.27	39.22	64.59
TiO₂	0.06	0.03	0.06	0.08	0.41	0.05
Al₂O₃	24.12	17.61	24.76	27.56	18.45	18.68
FeOt	1.34	7.79	4.73	3.34	5.65	0.1
NiO	0	0	0	0	0	0
MnO	0.04	0.08	0.17	0.12	1.78	0
MgO	0.17	0.89	2.64	2.98	0.02	0
CaO	0.32	1.66	0.13	0.04	34.42	0
Na₂O	14.81	13.91	0.03	0.02	0.03	0.45
K₂O	0.02	0	9.74	11.24	0.03	16.28
Cr₂O₃	0.05	0	0.06	0.01	0	0.09
TOT	100.29	99.61	95.76	96.66	100.01	100.23
Si	2.01	2	3.56	3.4	3	2.98
Al_IV	0	0	0.44	0.6	0	1.02
Al_VI	0.96	0.72	1.5	1.55	1.66
Ti	0	0	0		0.02	0
Fe²⁺	0.04	0.02	0.26	0.19	0.05	0
Fe³⁺	0	0.21		0	0.31
Mg	0.01	0.05	0.26	0.29	0	0
Mn	0	0	0.01	0.01	0.12	0
Na	0.97	0.94	0	0	0	0.04
Ca	0.01	0	0.01	0	2.82	0
K	0	0.06	0.83	0.95	0	0.96
Cr	0	0	0	0	0	0
SUM	4	4	6.87	6.99	7.98	5