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610219 
Journal Article 
Flatwater Pond Group: tectonostratigraphy and age constraints of an Ordovician ophiolite cover sequence, Baie Verte Peninsula, Newfoundland 
Kerr, IAN; Skulski, TOM; McNicoll, V; Castonguay, SB; Van Staal, CR 
2008 
Yes 
Atlantic Geology
ISSN: 0843-5561 
44 
58-58 
The Flat water Pond Group is situated on Baie Verte Peninsula and lies in the western part of the Dunnage Zone, along the Baie Verte Line. It unconformably overlies and is in fault contact with the Advocate Complex, a partially eroded ophiolitic complex consisting of peridotite, gabbro cumulates, sheeted dykes and very thin to non-existent boninitic lavas. Continental sedimentary and volcanic rocks of the Silurian (?) Micmac Lake Group unconformably overlies the Flatwater Pond Group. This study builds on previous bedrock mapping (work of W. Kidd in particular) and is augmented by a recent aeromagnetic survey and lithogeochemical and U/Pb geochronological data collected on key marker units. The lower Flatwater Pond Group consists of several conglomerate to megaconglomerate units likely derived from the underlying Advocate Complex and adjacent Laurentian continental margin (Fleur de Lys Supergroup). These are overlain by mafic pyroclastic rocks, tholeiitic pillow basalts, clinopyroxene megacrystic mafic tuff (lapilli tuff ), and associated pyroclastic rocks. The upper Flatwater Pond Group comprises tholeiitic pillow basalts and dacite, the former dated at ca. 476 Ma and containing Grenvillian- and Archean-age inherited zircons. The Flatwater Pond Group is interpreted to have been deposited on ophiolitic crust obducted onto the Laurentian continental margin during the Taconian Orogeny. It is correlative with tholeiitic volcanic cover sequences of similar age found across the Baie Verte Peninsula including the upper Pacquet Harbour and Snooks Arm groups. The Flatwater Pond Group sustained penetrative deformation during the Salinic Orogen and later brittle ductile deformation associated with the Baie Verte Road fault, which has resulted in a complex and polyphase tectonic history. [ABSTRACT FROM AUTHOR] Copyright of Atlantic Geology is the property of Atlantic Geology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts) 
OPHIOLITES; FAULT zones; VOLCANIC ash, tuff, etc.; GEOLOGY, Stratigraphic -- Silurian; GEOLOGY, Structural; BAIE Verte Peninsula (N.L.); NEWFOUNDLAND & Labrador