Piemontite-bearing Explosion Breccia in Archean Rocks, Labrador, Newfoundland
An explosion breccia, 4 km east of Hopedale, Labrador, occurs in Archean migmatite forming part of the Hopedale Gneiss. The breccia, 105 by 60 m, consists of angular to well-rounded fragments compositionally similar to the country rock. Extensive development of piemontite and epidote is characterist...
| Published in: | Canadian Journal of Earth Sciences |
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| Main Authors: | , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Canadian Science Publishing
1973
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| Subjects: | |
| Online Access: | http://dx.doi.org/10.1139/e73-129 http://www.nrcresearchpress.com/doi/pdf/10.1139/e73-129 |
| Summary: | An explosion breccia, 4 km east of Hopedale, Labrador, occurs in Archean migmatite forming part of the Hopedale Gneiss. The breccia, 105 by 60 m, consists of angular to well-rounded fragments compositionally similar to the country rock. Extensive development of piemontite and epidote is characteristic of the breccia. Two narrow mafic dikes post-date and fill fractures in the breccia. An electron probe analysis of piemontite and epidote shows the former contains 1.86% Mn 2 O 3 and the latter 0.21%. A genesis of the breccia involving fluidization with subsequent development of piemontite by hydrothermal activity is suggested. |
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