The evolution of the Baie Verte Lineament, Burlington Peninsula, Newfoundland

William Kidd, Apollo-University Of Cambridge Repository, Apollo-University Of Cambridge Repository
2012
An area measuring about 5 km by 30 km, of the relatively well-exposed central part of the Baie Verte Lineament, has been mapped in detail. Two major rock divisions are recognised by their differing structural and metamorphic histories. A terrain of psammitic, semipelitic and mafic schists borders the western side of the Lineament. These rocks (part of the Fleur de Lys Supergroup) are in upper greenschist to epidote-amphibolite metamorphic facies, and are affected by a polyphase deformation
more » ... nce. They are intruded by post-kinematic granite and tonalite. A large, generally unfoliated, granodiorite (Burlington Granodiorite) borders the eastern side of the Lineament. Outside the map area, it is seen to be either a pre- or early syn-kinematic intrusion into Fleur de Lys schists. The Baie Verte Lineament consists, in the mapped area, of two adjacent narrow-parallel belts; to the west the Baie Verte Group of uncertain (?Arenigian) age, and to the east the early Devonian Mic Mac Lake Group. Large lensoid "alpine-type" (ophiolitic) ultramafic bodies are situated along the tectonic contact between the Fleur de Lys schists and the Baie Verte Group. A narrow discontinuous strip containing bodies of ophiolitic gabbro with parallel diabase dykes is found at the western side of the Baie Verte Group adjoining the tectonic contact. The internal structures and textures of the ophiolitic rocks are described. The Baie Verte Group consists mainly of mafic pillow lava and mafic volcaniclastic sediments, subvertical to moderately west-dipping, and facing east, for which a stratigraphy is defined. At or near the base, a conglomerate, resting on ophiolite gabbro megabreccia, contains clasts mainly referable to the mafic parts of an ophiolite complex, with some clasts identical to the Burlington Granodiorite, and rare clasts referable to previously deformed silicic volcanics and related sediments of the Fleur de Lys Supergroup found to the east of the map area. Redeposited carbonate rocks are very occasionally found near this horizon. [...]
doi:10.17863/cam.15954 fatcat:3fx7m3yym5fohmbrnmv4lp6dny