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At 08:16 AM 13/11/2001 +0200, Malcolm Roberts wrote:
>Dugald,
>A worthy exercise, but maybe its more to do with frequency of occurence
>and what people have been studying rather than how popular a facies name
>is. How do you differentiate one from the other whilst wading through
>mountains of Georef?

No need to differentiate, Malc! IMHO for all these reasons (not much
occurrence, not much study, not popularly named) Turner's so-called "facies
of contact metamorphism" should be abandoned (as cogently recommended in
Miyashiro's textbook). In contact aureoles variation in grade is best
portrayed by mapping isograds and zones. SCMR would abandon
albite-epidote-hornfels and hornblende-hornfels facies; why cling to
pyroxene-hornfels and sanidinite facies? The facies classification is
practical for mapping only at the compilation scale (~1:5,000,000), where
the gradational boundaries between facies can be concealed beneath a
black-line contact.:-)

Cheers, Dugald