The Biotite-free assemblage: Muscovite+Chloritoid+Andalusite/Kyanite+Chlorite
occurs in graphitic aluminous pelites in the NW Iberian peninsula. The paper
"Evolution of a kyanite-bearing belt within a HT-LP orogen: the case of NW
Variscan Iberia" (J.Met.Geol: 16, 379-394. 1998) in a great part deals with
this subject. Further study on these particular rocks is now in press in the
same place.
Cheers,
Francisco J. Martinez
Dept. de Geologia
Univ. Autonoma de Barcelona
08193 Bellaterra, Barcelona
Spain
e-mail: [log in to unmask]
David Pattison wrote:
> Does anyone know of occurrences of the following rather rare metamorphic
> mineral assemblage:
>
> Muscovite+Chloritoid+chlorite+Al2SiO5 mineral (with or without biotite)
>
> Okuyama-Kusunose (J Met Geol 1994) reports extensive development of
> MsChlCtdBt and MsCtdAndBt in metamorphosed lateritic pelites in the Tono
> aureole, Japan, and alludes to the occurrence of MsCtdChlAnd(without Bt).
>
> The most likely rock types for these assemblages are aluminous metapelites,
> aluminous quartzites and metamorphosed altered felsic volcanics.
>
> David R.M. Pattison, Department of Geology and Geophysics,
> University of Calgary, Calgary, Alberta, T2N 1N4, Canada.
> Phone: 403-220-3263 (my office); 403-220-5841 (dept. office)
> Fax: 403-284-0074 email: [log in to unmask]
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