Régnier - I have also seen a number of individual samples in
which Ms+St+Crd+Bt appear together, seemingly in equilibrium. Some
pictures appear in the paper referenced below. In my experience, Crd
generally surrounds or from other criteria is generally late texturally
compared to the St and when present andalusite, although in some cases it
is very hard to say one way or the other. If it weren't for some pretty
serious topological problems that arise in in the metapelite grid when
you treat this as a stable assemblage, there would seem to be no reason
to doubt its stability. This is why we emphasized having to examine the
assemblage in its broader context. The arguments are in the paper.
Returning to your sample, I would check that there is stable Ms in it (if
not, that changes everything), and entertain the possibility of unstable
persistence of St into a lower pressure Crd-bearing assemblage.
In relation with the paper from Pattison and al "
polymetamorphic origin of muscovite + cordierite + Staurolite + biotite
" (1999), I would like to know yours opinions about this thins
section (attachment) found in " la Montagne Noire " (France)
where the equilibrium at Tmax seems to be obvious.
Do you know some other examples like this?
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