Dima,
I am not a TWEEQ expert. However, I do not think that anyone has
systematically worked out the a/X of cordierite for both H2O and CO2 in the
channels, although the reduction of the activity of H2O in a fluid by
dilution with CO2 should shift the stability of hydrous cordierite. Do we
even know if the peak fluids are preserved in metamorphic cordierite that
has cooled?
eric
>Dear TWQ experts,
>
>In TWQ2.02b DOCs (and relating paper: Berman, Aranovich, 1996, CMP:126, 1-24),
>I've read that some Crd hydration model (affecting mineral energetics) has
>been
>accepted. However, I've noticed that P(T)-locations of any equilibria with
>cordierites (+ those corresponding to net-transfer reactions) are absolutely
>insensitive to any H2O-CO2 settings. I supposed that changes in a(H2O|CO2)
>settings in couple with such Crd models should influence PT results.
>Am I wrong?
>
>P.S. I've sent this question to [log in to unmask] once (in April, 2001),
> but, unfortunately, I haven't receive any reply, yet:(
>
>Thanks in advance,
>Dima DD.
>
>--
>_________________________________________________________________________
>Dmitry V. Dolivo-Dobrovolsky
>Institute of Precambrian Geology and Phone: +7(812)273-02-79 home
>Geochronology, the Russian Academy +7(812)328-03-62 work
>of Sciences Fax: +7(812)328-48-01 work
>Makarova emb. 2
>199034 St.-Petersburg E-mail: [log in to unmask]
>RUSSIA
Eric Essene
Professor of Geology
Department of Geological Sciences
2534 C.C. Little Bldg.
425 E. University Ave.
University of Michigan
Ann Arbor MI 48109-1063 USA
fx: 734-763-4690
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