Evidence of Late Ediacaran Hyperextension of the Laurentian Iapetan Margin in the Birchy Complex, Baie Verte Peninsula, Northwest Newfoundland: Implications for the Opening of Iapetus, Formation of PeriLaurentian Microcontinents and Taconic – Grampian Orogenesis
The Birchy Complex of the Baie Verte Peninsula, northwestern Newfoundland, comprises an assemblage of mafic schist, ultramafic rocks, and metasedimentary rocks that are structurally sandwiched between overlying ca. 490 Ma ophiolite massifs of the Baie Verte oceanic tract and underlying metasedimenta...
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ftconicet:oai:ri.conicet.gov.ar:11336/11473 2023-10-09T21:50:05+02:00 Evidence of Late Ediacaran Hyperextension of the Laurentian Iapetan Margin in the Birchy Complex, Baie Verte Peninsula, Northwest Newfoundland: Implications for the Opening of Iapetus, Formation of PeriLaurentian Microcontinents and Taconic – Grampian Orogenesis Van Staal, Cees R. Chew, Dave M. Zagorevski, Alexandre Mcnicoll, Vicki Hibbard, James Skulski, Tom Castonguay, Sébastien Escayola, Monica Patricia Sylvester, Paul J. application/pdf http://hdl.handle.net/11336/11473 eng eng Geological Assoc Canada info:eu-repo/semantics/altIdentifier/url/https://journals.lib.unb.ca/index.php/GC/article/view/geocanj.2013.40.006 http://hdl.handle.net/11336/11473 Van Staal, Cees R.; Chew, Dave M.; Zagorevski, Alexandre; Mcnicoll, Vicki; Hibbard, James; et al.; Evidence of Late Ediacaran Hyperextension of the Laurentian Iapetan Margin in the Birchy Complex, Baie Verte Peninsula, Northwest Newfoundland: Implications for the Opening of Iapetus, Formation of PeriLaurentian Microcontinents and Taconic – Grampian Orogenesis; Geological Assoc Canada; Geoscience Canada; 40; 2; 12-2013; 94-117 0315-0941 info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ Ediacarian Iapetus Taconic Origenesis https://purl.org/becyt/ford/1.5 https://purl.org/becyt/ford/1 info:eu-repo/semantics/article info:ar-repo/semantics/artículo info:eu-repo/semantics/publishedVersion ftconicet 2023-09-24T20:06:41Z The Birchy Complex of the Baie Verte Peninsula, northwestern Newfoundland, comprises an assemblage of mafic schist, ultramafic rocks, and metasedimentary rocks that are structurally sandwiched between overlying ca. 490 Ma ophiolite massifs of the Baie Verte oceanic tract and underlying metasedimentary rocks of the Fleur de Lys Supergroup of the Appalachian Humber margin. Birchy Complex gabbro yielded a Late Ediacaran U–Pb zircon ID–TIMS age of 558.3 ± 0.7 Ma, whereas gabbro and an intermediate tuffaceous schist yielded LA–ICPMS concordia zircon ages of 564 ± 7.5 Ma and 556 ± 4 Ma, respectively. These ages overlap the last phase of rift-related magmatism observed along the Humber margin of the northern Appalachians (565–550 Ma). The associated ultramafic rocks were exhumed by the Late Ediacaran and shed detritus into the interleaved sedimentary rocks. Psammite in the overlying Flat Point Formation yielded a detrital zircon population typical of the Laurentian Humber margin in the northern Appalachians. Age relationships and characteristics of the Birchy Complex and adjacent Rattling Brook Group suggest that the ultramafic rocks represent slices of continental lithospheric mantle exhumed onto the seafloor shortly before or coeval with magmatic accretion of mid-ocean ridge basalt-like mafic rocks. Hence, they represent the remnants of an ocean – continent transition zone formed during hyperextension of the Humber margin prior to establishment of a mid-ocean ridge farther outboard in the Iapetus Ocean. We propose that microcontinents such as Dashwoods and the Rattling Brook Group formed as a hanging wall block and an extensional crustal allochthon, respectively, analogous to the isolation of the Briançonnais block during the opening of the Alpine Ligurian–Piemonte and Valais oceanic seaways. Le complexe de Birchy de la péninsule de Baie Verte, dans le nord-ouest de Terre-Neuve, est constitué d’un assemblage de schistes mafiques, de roches ultramafiques et de métasédiments qui sont coincés entre des massifs ... Article in Journal/Newspaper Baie Verte Newfoundland Terre-Neuve CONICET Digital (Consejo Nacional de Investigaciones Científicas y Técnicas) Verte ENVELOPE(141.192,141.192,-66.740,-66.740) Baie Verte ENVELOPE(-56.182,-56.182,49.933,49.933) Fleur de Lys ENVELOPE(-56.131,-56.131,50.117,50.117) Baie Verte Peninsula ENVELOPE(-56.498,-56.498,49.833,49.833) Rattling Brook ENVELOPE(-57.882,-57.882,49.500,49.500) Flat Point ENVELOPE(-56.415,-56.415,49.917,49.917) |
institution |
Open Polar |
collection |
CONICET Digital (Consejo Nacional de Investigaciones Científicas y Técnicas) |
op_collection_id |
ftconicet |
language |
English |
topic |
Ediacarian Iapetus Taconic Origenesis https://purl.org/becyt/ford/1.5 https://purl.org/becyt/ford/1 |
spellingShingle |
Ediacarian Iapetus Taconic Origenesis https://purl.org/becyt/ford/1.5 https://purl.org/becyt/ford/1 Van Staal, Cees R. Chew, Dave M. Zagorevski, Alexandre Mcnicoll, Vicki Hibbard, James Skulski, Tom Castonguay, Sébastien Escayola, Monica Patricia Sylvester, Paul J. Evidence of Late Ediacaran Hyperextension of the Laurentian Iapetan Margin in the Birchy Complex, Baie Verte Peninsula, Northwest Newfoundland: Implications for the Opening of Iapetus, Formation of PeriLaurentian Microcontinents and Taconic – Grampian Orogenesis |
topic_facet |
Ediacarian Iapetus Taconic Origenesis https://purl.org/becyt/ford/1.5 https://purl.org/becyt/ford/1 |
description |
The Birchy Complex of the Baie Verte Peninsula, northwestern Newfoundland, comprises an assemblage of mafic schist, ultramafic rocks, and metasedimentary rocks that are structurally sandwiched between overlying ca. 490 Ma ophiolite massifs of the Baie Verte oceanic tract and underlying metasedimentary rocks of the Fleur de Lys Supergroup of the Appalachian Humber margin. Birchy Complex gabbro yielded a Late Ediacaran U–Pb zircon ID–TIMS age of 558.3 ± 0.7 Ma, whereas gabbro and an intermediate tuffaceous schist yielded LA–ICPMS concordia zircon ages of 564 ± 7.5 Ma and 556 ± 4 Ma, respectively. These ages overlap the last phase of rift-related magmatism observed along the Humber margin of the northern Appalachians (565–550 Ma). The associated ultramafic rocks were exhumed by the Late Ediacaran and shed detritus into the interleaved sedimentary rocks. Psammite in the overlying Flat Point Formation yielded a detrital zircon population typical of the Laurentian Humber margin in the northern Appalachians. Age relationships and characteristics of the Birchy Complex and adjacent Rattling Brook Group suggest that the ultramafic rocks represent slices of continental lithospheric mantle exhumed onto the seafloor shortly before or coeval with magmatic accretion of mid-ocean ridge basalt-like mafic rocks. Hence, they represent the remnants of an ocean – continent transition zone formed during hyperextension of the Humber margin prior to establishment of a mid-ocean ridge farther outboard in the Iapetus Ocean. We propose that microcontinents such as Dashwoods and the Rattling Brook Group formed as a hanging wall block and an extensional crustal allochthon, respectively, analogous to the isolation of the Briançonnais block during the opening of the Alpine Ligurian–Piemonte and Valais oceanic seaways. Le complexe de Birchy de la péninsule de Baie Verte, dans le nord-ouest de Terre-Neuve, est constitué d’un assemblage de schistes mafiques, de roches ultramafiques et de métasédiments qui sont coincés entre des massifs ... |
format |
Article in Journal/Newspaper |
author |
Van Staal, Cees R. Chew, Dave M. Zagorevski, Alexandre Mcnicoll, Vicki Hibbard, James Skulski, Tom Castonguay, Sébastien Escayola, Monica Patricia Sylvester, Paul J. |
author_facet |
Van Staal, Cees R. Chew, Dave M. Zagorevski, Alexandre Mcnicoll, Vicki Hibbard, James Skulski, Tom Castonguay, Sébastien Escayola, Monica Patricia Sylvester, Paul J. |
author_sort |
Van Staal, Cees R. |
title |
Evidence of Late Ediacaran Hyperextension of the Laurentian Iapetan Margin in the Birchy Complex, Baie Verte Peninsula, Northwest Newfoundland: Implications for the Opening of Iapetus, Formation of PeriLaurentian Microcontinents and Taconic – Grampian Orogenesis |
title_short |
Evidence of Late Ediacaran Hyperextension of the Laurentian Iapetan Margin in the Birchy Complex, Baie Verte Peninsula, Northwest Newfoundland: Implications for the Opening of Iapetus, Formation of PeriLaurentian Microcontinents and Taconic – Grampian Orogenesis |
title_full |
Evidence of Late Ediacaran Hyperextension of the Laurentian Iapetan Margin in the Birchy Complex, Baie Verte Peninsula, Northwest Newfoundland: Implications for the Opening of Iapetus, Formation of PeriLaurentian Microcontinents and Taconic – Grampian Orogenesis |
title_fullStr |
Evidence of Late Ediacaran Hyperextension of the Laurentian Iapetan Margin in the Birchy Complex, Baie Verte Peninsula, Northwest Newfoundland: Implications for the Opening of Iapetus, Formation of PeriLaurentian Microcontinents and Taconic – Grampian Orogenesis |
title_full_unstemmed |
Evidence of Late Ediacaran Hyperextension of the Laurentian Iapetan Margin in the Birchy Complex, Baie Verte Peninsula, Northwest Newfoundland: Implications for the Opening of Iapetus, Formation of PeriLaurentian Microcontinents and Taconic – Grampian Orogenesis |
title_sort |
evidence of late ediacaran hyperextension of the laurentian iapetan margin in the birchy complex, baie verte peninsula, northwest newfoundland: implications for the opening of iapetus, formation of perilaurentian microcontinents and taconic – grampian orogenesis |
publisher |
Geological Assoc Canada |
url |
http://hdl.handle.net/11336/11473 |
long_lat |
ENVELOPE(141.192,141.192,-66.740,-66.740) ENVELOPE(-56.182,-56.182,49.933,49.933) ENVELOPE(-56.131,-56.131,50.117,50.117) ENVELOPE(-56.498,-56.498,49.833,49.833) ENVELOPE(-57.882,-57.882,49.500,49.500) ENVELOPE(-56.415,-56.415,49.917,49.917) |
geographic |
Verte Baie Verte Fleur de Lys Baie Verte Peninsula Rattling Brook Flat Point |
geographic_facet |
Verte Baie Verte Fleur de Lys Baie Verte Peninsula Rattling Brook Flat Point |
genre |
Baie Verte Newfoundland Terre-Neuve |
genre_facet |
Baie Verte Newfoundland Terre-Neuve |
op_relation |
info:eu-repo/semantics/altIdentifier/url/https://journals.lib.unb.ca/index.php/GC/article/view/geocanj.2013.40.006 http://hdl.handle.net/11336/11473 Van Staal, Cees R.; Chew, Dave M.; Zagorevski, Alexandre; Mcnicoll, Vicki; Hibbard, James; et al.; Evidence of Late Ediacaran Hyperextension of the Laurentian Iapetan Margin in the Birchy Complex, Baie Verte Peninsula, Northwest Newfoundland: Implications for the Opening of Iapetus, Formation of PeriLaurentian Microcontinents and Taconic – Grampian Orogenesis; Geological Assoc Canada; Geoscience Canada; 40; 2; 12-2013; 94-117 0315-0941 |
op_rights |
info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ |
_version_ |
1779313154587623424 |