Dear all,
Your lively discussion on metasomatism entertained me a lot. However,
please consider the following not uncommon situation: Starting material
is a pure monomineralic dolomite marble. The marble reacts with an
SiO2-saturated fluid advecting on fractures cutting across the marble.
The resulting metasomatic rock consists of about 70 vol.% tremolite and
30 vol.% calcite. This means that the original rock consists of one
phase (dolomite) and the metasomatic rock consists of two phases (Tr +
Cal). This is a 100% increase in the number of phases from the source
rock to the metasomatic rock. Say hello to Mr. Kozinski. Korzinski, of
course, was not wrong. But the counting of components, phases, mobile
components, independent variables and all that is to complex for the
average geologist to be of any practical use.
Cheers
Kurt
Bucher-Nurminen, K., 1981, The formation of metasomatic reaction veins
in dolomitic marble roof pendants in the Bergell intrusion (Province
Sondrio, Northern Italy). Am. Jour. Sci., 281, 1197-1222.
Bucher-Nurminen, K., 1989, Reaction veins in marbles formed by a
fracture-reaction-seal mechanism. European J. Mineral., 1, 701-714.
Bucher, K., 1998, Growth mechanisms of metasomatic reaction veins in
dolomite marbles from the Bergell Alps. Mineralogy and Petrology, 63,
151-171.
--
Kurt Bucher (Prof. Dr.)
Institute of Mineralogy and Geochemistry
University of Freiburg
Albertstrasse 23b D-79104 Freiburg Germany
Phone 49-761-203-6395 (direct) 6396 (general office) 6407 (FAX)
http://www.minpet.uni-freiburg.de
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