It is a sad comment on where Metamorphic Petrology has got to, that some of
us do not appear to read the scientific content of each other's emails any
more, we just worry about terminology. I attempted to make the scientific
point, which Jorge Julian Restrepo has also picked up on, that, although we
all agree that there are a wide range of P-T conditions in which either
classic hornfelses or apparently normal regionally metamorphosed rocks may
be produced, there are some extreme conditions of high-T, low-P contact
metamorphism with no regional equivalents, in which some very distinctive
assemblages are produced. The science behind why this should be the case is
clearly of interest. The fact that I referred in passing to Turner's
regional/honfels facies terminology, even though it was only to point out
that it was not appropriate, may perhaps be of interest to lexicographers
but it is not of scientific interest. I would like to propose that someone
sets up a separate geo-lexicography mailing list for people who want to
discuss matters of pure terminology.
Bruce Yardley
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Professor Bruce Yardley
School of Earth Sciences
University of Leeds
Leeds LS2 9JT
UK
Tel. 0113 233 5227 Fax 0113 233 5259
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GEOFLUIDS now exists! http://www.blackwell-science.com/gfl
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