Geology and petrochemistry of ophiolitic rocks of the Baie Verte Group exposed at Ming's Bight, Newfoundland
The Baie Verte Group, as exposed on the peninsula between Baie Verte and Ming's Bight, consists of a disrupted ophiolite sequence. The rock types range from interlayered ultramafics and gabbro to sheeted diabase dikes overlain by pillow lavas and volcanic sediments. The sequence has been disrup...
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Format: | Thesis |
Language: | English |
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Memorial University of Newfoundland
1973
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Online Access: | https://research.library.mun.ca/6822/ https://research.library.mun.ca/6822/1/Ryburn_E_Norman.pdf https://research.library.mun.ca/6822/3/Ryburn_E_Norman.pdf |
Summary: | The Baie Verte Group, as exposed on the peninsula between Baie Verte and Ming's Bight, consists of a disrupted ophiolite sequence. The rock types range from interlayered ultramafics and gabbro to sheeted diabase dikes overlain by pillow lavas and volcanic sediments. The sequence has been disrupted into five structural blocks separated by fault zones containing serpentinized peridotite and/or talc-carbonate; units within each block are separated by less significant faults. This widespread imbrication is similar to 'schuppen zones' in north-east Shetland as described by Flinn (1958). These structures and other deformation features in the Baie Verte Group are interpreted to be related to early Ordovician emplacement with some effects of later Acadian deformation. -- The Baie Verte Group is chemically similar to other ophiolite sequences such as in Oman and Papua. A parental magma, interpreted to have been a low-Ti and low-K basaltic magma, crystallized under conditions of low oxygen fugacity in the upper crustal zones beneath a mid-ocean ridge, producing the ultramafics-gabbro-diabase-pillow lava sequence observed. -- Mineral occurrences in the area have similar mineralogy (pyrite-chalcopyrite-pyrrhotite-sphalerite) to those of other ophiolite areas such as Betts Cove and Troodos. |
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