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Dear Dr. Camacho, There is one such case which is almost what you are looking for. In the Almora Nappe, which is one of the largest nappes of Himalaya thrust southwards during the Tertiary orogeny, metapelites from chlorite to K-feldspar sillimanite(needle) zone are exposed. Our detailed recent studies(unpublished) have shown that this metamorphism culminated in anatexis resulting in the Almora gneisses(dated at ~1800my). This sequence has been folded and intruded by a Cambroordovician granitoid(dated ~560 my) resulting in contact metamorphic aureole which has preserved andalusite (Joshi et al., 1993, Curr. Science) In case you are interested I can send other details and I am also willing to collaborate on this very interesting aspect on which you are working. Yours sincerely Mallickarjun Joshi Professor Department of Geology Banaras Hindu University Varanasi 221 005 INDIA Email: [log in to unmask] ----- Original Message ----- From: Alfredo Camacho <[log in to unmask]> To: <[log in to unmask]> Sent: Monday, January 22, 2001 10:19 AM Subject: Contact aureoles > Dear all, > > I am looking for a rapidly cooled metamorphic terrane, containing garnet, > that was intruded at a much later date (in the hundreds Ma) by a granite > (or other heat source). It would be nice if garnet was found in most of > the isograds associated with the granite aureole. In addition, alteration > associated with cooling and or hydrous fluids should be minimal. > > The reason for this specific setting is that I want to use the granite > thermal overprint as a natural experiment to determine the closure > temperature of garnet by looking at diffusion profiles in garnet. This has > a much better chance of success than carrying out laboratory diffusion > experiments because REE diffuse slowly. > > Cheers > > Alfredo > > Alfredo Camacho > School of Geology, > The University of New South Wales, > UNSW SYDNEY, NSW 2052, > AUSTRALIA > > Tel no: (02) 9385 (6142 or 6134) > Fax no: (02) 9385 5935 > Email: [log in to unmask]