Skip to main content

Table 4 Intervals of compositional variations in minerals marking different metamorphic stages of orthogneiss

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 pre-1 M1 M2/D2
Grt   Mg = 0  
   Fe2+ = 0.03–0.09  
   Fe3+ = 0.21–0.38  
   Ca = 2.74–2.85  
   Mn = 0.10–0.17  
Jd   XJd = 0.87–0.99 XJd = 0.50–0.88
   Na = 0.92–0.99 Na = 0.84–0.99
   Fe = 0.01–0.13 Fe = 0.12–0.41
   Ca = 0.00–0.04 Ca = 0.02–0.11
   Mg = 0.00–0.04 Mg = 0.01–0.08
Wm   Si = 3.47–3.65 Si = 3.35–3.48
   Altot = 1.86–2.07 Altot = 2.05–2.22
   Ti = 0 Ti = 0.00–0.01
   Mg = 0.24–0.33 Mg = 0.28–0.33
Kfs XAb = 0.02–0.04   
  XAn = 0   
  XOr = 0.96-0.98