Dear James:
Thanks a lot for your interest. I see quite interesting your suggestion
about patchy zonation of amphiboles. Nevertheless, I've got no data about
fluids in these rocks.
Yes, I've got some comments: I'm sorry I didn't say that the Cpx I've got is
diopside and I can't get Pargasite from Diopside, since I need Na and Al,
which can't be supplied by diopside. Probably, I didn't give all the clues
needed to understand the situation. The problem is that, even if there is no
equilibrium, there must be a metamorphic evolution from Pargasite (high
temperature), through Mg-Hbl, to actinolite or the way back. Anyway, no
Pargasite have been found in the Cpx bearing assemblages, which are supposed
to be the highest ones. So, it's hard to explain that in lower zones there
is Pargasite. I'm thinking that perhaps, these Pargasites could be igneous
relics. What do you think?
Cheers
Manuel
--
Manuel Díaz Azpiroz
Dpto. Geología, Universidad de Huelva
Campus de La Rábida. Crtra. Palos de la Frontera s/n
21087 Huelva
Tf: 959-351000/351012
Fax: 959-530175
E-mail: [log in to unmask]
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