<p> Coronite amphibolites located near the western contact of the.
Whitestone Lake Anorthosite were studied in the field and laboratory in
order to determine their origin. The corona textures consisted of
garnet cores surrounded by complete rims of plagioclase, which in turn
were occasionally surrounded by partial or complete rims of garnet or
pyroxene. The development of coronas is also accompanied by an increase
in pyroxene in the rock, and the development of cryptic zoning in both
garnets and plagioclases. Whole rock X-Ray Fluorescence and mineral
electron-probe analyses were determined for suites of samples collected.
The analyses suggest that corona development occurred isochemically as the
result of a contact metamorphism induced by anorthosite emplacement and
mineral reactions have been proposed. Microprobe analyses of the garnets
led to the establishment of models for the production of garnets in mafic
assemblages and models for the observed cryptic zoning in the garnets~
It was concluded that the coronites represent the transition from
almandine amphibolite facies to clinopyroxene subfacies of granulite
metamorphism of garnetiferous amphibolites. This transition results from
the thermal metamorphism induced by the emplacement of the Whitestone
lake anorthosite. </p> / Thesis / Doctor of Philosophy (PhD)
| Identifer | oai:union.ndltd.org:mcmaster.ca/oai:macsphere.mcmaster.ca:11375/19752 |
| Date | 12 1900 |
| Creators | Mummery, Robert |
| Contributors | McNutt, R. H., Geology |
| Source Sets | McMaster University |
| Language | English |
| Detected Language | English |
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