Sebastián,
After analyzing the peak metamorphic phases, you should try
using Holland & Powell to see about limits on their stability. The T
will depend strongly on the Mg/Fe in the actinolite.
cheers,
eric
On Jun 23, 2009, at 10:00 AM, Sebastián Verdecchia wrote:
> Hi all
>
> I am studying quartzites with actinolite paragenetic (complete
> paragenesis: Qtz-Pl-Act±Ep±Chl and opaques). The actinolite was
> classification from diagram suggested by Leake et al. (1997). These
> rocks suffer low pressure condition (<2.5 kb) and a temperature
> about 600-650º C established from quartz-micaceous schist located in
> contact with these quartzites.
> Chlorite and epidote would be product from retrograde reaction: Act
> +Pl+H2O --> Ep + Chl
>
> My question is, Could actinolite be stable at about 600-650 ºC? Does
> somebody know some works about stability of actinolite in middle- to
> high-grade metamorphism in quartzites or calcosilicates?
>
> Thank you in advance,
>
> Sebastián Verdecchia
>
>
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