Thanks, Robert, for the web address of the SCMR proposal
(www.bgs.ac.uk/scmr). Very useful indeed and I feel that most of the recent
questions on the nomenclature have an answer there.
Frank said "Particularly so since most gneisses are blastomylonites".
Maybe true (I do not know Frank's definition of gneiss) although in the SCMR
framework, a blastomylonite should have a well-developed schistosity while a
gneiss should have a schistosity either poorly developed or if
well-developed, only in broadly shaped zones.
This demonstrates the usefulness of a well-constrained terminology in
discussions.
Jean-Paul
Jean-Paul Liegeois
Head of Section, Isotope Geology
Africa Museum
B-3080 Tervuren, Belgium
Tel & Fax: +32 (0)2 6502252
e-mail: [log in to unmask]
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