A suite of alkali basalts and gabbros associated with the Hare Bay Allochthon of western Newfoundland

The Hare Bay Allochthon of northwestern Newfoundland consists of a series of sedimentary, volcanic, metamorphic, and ultramafic rocks which was emplaced over a Cambro-Ordovician continental margin as several thrust sheets. It probably represents a continental margin sequence overridden by oceanic cr...

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Bibliographic Details
Published in:Canadian Journal of Earth Sciences
Main Author: Jamieson, R. A.
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 1977
Subjects:
Online Access:http://dx.doi.org/10.1139/e77-036
http://www.nrcresearchpress.com/doi/pdf/10.1139/e77-036
Description
Summary:The Hare Bay Allochthon of northwestern Newfoundland consists of a series of sedimentary, volcanic, metamorphic, and ultramafic rocks which was emplaced over a Cambro-Ordovician continental margin as several thrust sheets. It probably represents a continental margin sequence overridden by oceanic crust and upper mantle. The Partridge Point gabbro, Cape Onion volcanics, and Ireland Point Volcanics, which now occur in the Maiden Point, Cape Onion, and St. Anthony tectonic slices respectively, appear to be closely related on petrographic and chemical grounds. Olivine, titanaugite, kaersutite, and plagioclase indicate that these rocks formed as a single suite of hydrous alkali basalts, possibly as part of a seamount near a continental margin. This relationship provides a link between the lower sedimentary and the upper igneous-metamorphic structural slices of the allochthon and implies that most of the transported rocks in the Hare Bay area evolved in close proximity to each other.