Dear All,
Thank you very much for 2Fsp thermometric programs and refs to websites:
with your help, I've got 'em all!
But, I have another question regarding these programs - and, especially,
ternary feldspar model of Fuhrman & Lindsley, 1988 (AM'88, NN3-4,
pp.201-215). I've been surprised that I cannot reproduce T's calculated by
2Fsp programs (with F&L'88 model and even fixed mineral compositions).
Comparison of W-parameters revealed that enthalpy terms (WH) for An-Or join
are in opposite places in the paper and SOLVCALC database (i.e. WH[AnOr]
and WH[OrAn] are swapped somewhere). So, the question is: where is a typo -
in the paper, or in all the programs I have got now? T's presented in the
same paper suggested me, that typo is in its table with Margules
parameters...
This may be interesting for those who use TWQ program: its databases use
F&L'88 model with parameters taken directly from that table;) Otherwise,
what's about MTHERM3 and SOLVCALC?
To say, such swapping lead to 74(!)deg. differences in calculated
"anorthitic" temperatures for the trachyte sample from Carmichael (1965)
(1st sample from Table 3, F&L'88, calced with fixed compositions).
Thanks,
Dima DD.
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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
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