Steve
A nice paper dealing with the stability of this sort of assemblage is
Simpson et al. (2000). If you don't want to embark on mineral analysis it
might help- for some approximations.
Simpson G.D.H., Thompson, A.B., Conolly, J.A.D., 2000. Phase relations,
singularities and thermobarometry of metamorphic assemblages containing
phengite, chlorite, biotite, K-feldspar, quartz and H2O. Contributions to
Mineralogy and Petrology 139, 555-569.
Cheers,
Steffen
-----Original Message-----
From: Metamorphic Studies Group [mailto:[log in to unmask]] On
Behalf Of Steven Kidder
Sent: 14 December 2011 22:07
To: [log in to unmask]
Subject: Minimum T for biotite?
Hi, I'd like to know the minimum temperature needed for the appearance of
metamorphic biotite in a typical metamorphosed sandstone. I'm a structural
geologist and couldn't find a relevant reference after a couple hours
literature search. The quartzite I'm working on contains ~70% quartz, lithic
fragments (predominantly volcanics and slate), detrital feldspar, mica, and
some Fe and FeTi oxides. The only clearly metamorphic minerals I've see are
chlorite and biotite growing in pressure shadows.
thanks,
Steve Kidder
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