At 11:57 AM 09/11/2001 +0900, Shohei Banno wrote:
>...
> From another subcommision [of the SCMR] I received questionnaire a few years
>ago, and I strongly argued that the subcommision should not try to
>define a metamorphic facies by voting. Such a subject should be debated
>in papers.
> I understand the complexity of leading the subcommission, but I
>expect to know how common is a rock name is used for what. Thus we need
>a poll of public opinion but not voting, though the former may be more
>difficult to perform.
>...

One can make a rough "poll of public opinion" by searching the GeoRef
database for the number of papers with specific words or strings of words
in their titles and keyword listings etc. Draft paper #3 on the SCMR
website distinguishes ten metamorphic facies by name, and "recommends that
only these ten facies be generally adopted." Below are listed these ten
facies and the number of papers in GeoRef that use them (with or without
hyphens).

amphibolite facies            5487
greenschist facies            4724
granulite facies              4555
eclogite facies                895
prehnite-pumpellyite facies    341
zeolite facies                 269
epidote-amphibolite facies     223
glaucophane-schist facies       74
pyroxene-hornfels facies        20
sanidinite facies                4

It seems likely that undergrads have been wasting their time memorizing the
facies of contact metamorphism.:-) And "glaucophane-schist facies" has only
one GeoRef hit for every 11 "blueschist facies" hits (74 to 838). SCMR
concedes that "the glaucophane-schist facies is often now referred to as
blueschist facies", but I wish they would OPT for blueschist facies! With
the understanding that "blueschist" in a facies context means "metabasite"
and not just "blue-amphibole rock", mineral modifiers could readily be used
to specify more restricted ranges of grade:

jadeite-blueschist facies
lawsonite-blueschist facies
pumpellyite-blueschist facies
epidote-blueschist facies

Cheers, Dugald
Dugald M Carmichael                    Phone/V-mail: 613-533-6182
Dept of Geological Sciences and Geological Engineering
Queen's University                              FAX: 613-533-6592
Kingston  ON  K7L3N6             E-mail: [log in to unmask]