Petrology, geochemistry, and geochronology of some Precambrian rocks of the north-western Melville Peninsula, Northwest Territories
The northwestern Melville Peninsula in the area of 69°34'N/84°50'W consists of Precambrian Shield rocks that have suffered multiple metamorphic events, including a high grade metamorphic event in the late Archean, ranging from upper amphibolite to granulite grade locally. The oldest unit p...
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| Other Authors: | , |
| Language: | English |
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1985
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| Online Access: | http://hdl.handle.net/11375/19549 |
| Summary: | The northwestern Melville Peninsula in the area of 69°34'N/84°50'W consists of Precambrian Shield rocks that have suffered multiple metamorphic events, including a high grade metamorphic event in the late Archean, ranging from upper amphibolite to granulite grade locally. The oldest unit present is a tonalite-granodiorite-granite suite showing both foliation and lineation and a somewhat migmatic texture. This biotite-hornblende orthogneiss has produced a Rb-Sr whole rock age date of 2.55 +/- 0.2 Ga. Field relationships indicate that this is a metamorphically induced age rather than an emplacement age. A coarse grained granitic pegmatite associated with the orthogneiss has produced a Rb-Sr isochron indicating an age of 1.83 +/- 0.06 Ga. Petrographic and field evidence indicate that this represents the emplacement age of the pegmatite. Thesis Bachelor of Science (BSc) |
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