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?
Malc.
Dugald Carmichael wrote:
> 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]
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