Dear all,
I am working with some sapphirine bearing rocks from central Brazil. In
one sample Spr+Qtz are rare and occuring in contact only as inclusions
inside Grt. Some Grt grains are substituted by Crd+Spl+Sil and in
subsequent step Grt has its borders substituted by Opx+Crd+/-Bt. I
interpret that these assemblages were formed by the breakdown of Qtz+Spr
at an ITD P-T path followed by some cooling (?) until the remained Grt be
consumed by the reaction:
Qtz+Grt+melt=Opx+Crd+Bt
The topology of this reaction appears in the Fig 3.11 of Grant (1985). Is
there any petrogenetic grid with this reaction plotted in a quantified P-T
space? Can anybody help me?
Best regards
Renato
Grant, J.A. 1985. Phase equilibria in partial melting of pelitic rocks. In:
Ashworth, J.R. (ed). Migmatites, 86 - 144. Glasgow: Blackie.
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