Carl
quite interesting because St-Crd isn't a typical barrovian assemblage
and is quite uncommon.
I guess Dave Pattison will want to comment on this.
Bernardo
> <!-- p { margin-top: 0px; margin-bottom: 0px; }-->
> Dear metamorphic community,
>
>
>
> We're working on a suite of archean paragneiss (Opinaca subprovince,
> Superior Craton) that display a barrovian-type sequence of isograds
> (bt-gt-st-sill). In the field, we have noticed a blueish-greenish mineral
> in the pressure shadows of early kinematic staurolite, and thought it's
> either chlorite or cordierite. However, in thin section, the mineral has
> clearly been altered and shows a heterogeneous chemical composition (see
> attached document for pictures and probe analyses).
>
>
>
> We are looking for ways to confirm or infirm that the altered mineral was
> once cordierite.
>
>
>
> Any comments/advice/references will be greatly appreciated.
>
>
>
> Best regards
>
>
>
> Carl and Myriam
> ____________________________________________
>
> Carl Guilmette, PhD. Eng.
> Professeur Adjoint
> Chaire de Leadership en Enseignement Virginia-Gaumond
> Département de Géologie et Génie Géologique
> Université Laval
> 1-418-656-2131 poste 3137
--
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Bernardo Cesare
Dipartimento di Geoscienze, Universita' di Padova
Via G. Gradenigo, 6, I-35131 PADOVA ITALY
Tel: ++39-049-8279148 Fax: ++39-049-8279134
email: [log in to unmask]
Web site: http://147.162.183.153/bernardo/berning.html
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MicROCKScopica: http://www.microckscopica.org
InsiemePerWamba: http://www.insiemeperwamba.org
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