Lithostratigraphy and lithogeochemistry of Ediacaran alkaline basaltic rocks of the Musgravetown Group, Bonavista Peninsula, northeastern Newfoundland, Canada: an extensional volcanogenic basin in the type-Avalon terrane
Volcanic rocks of the Ediacaran Musgravetown Group on Bonavista Peninsula, Avalon terrane, Newfoundland, include basal ca. 600 Ma calc-alkaline basalt succeeded by continental tholeiite and alkaline rhyolite of the ca. 592 Ma Plate Cove volcanic belt (Bull Arm Formation), indicating a change from su...
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Atlantic Geoscience Society
2021
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Online Access: | https://doi.org/10.4138/atlgeol.2021.010 http://id.erudit.org/iderudit/1082236ar |
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fttriple:oai:gotriple.eu:10670/1.fnrh1l 2023-05-15T17:22:02+02:00 Lithostratigraphy and lithogeochemistry of Ediacaran alkaline basaltic rocks of the Musgravetown Group, Bonavista Peninsula, northeastern Newfoundland, Canada: an extensional volcanogenic basin in the type-Avalon terrane Mills, Andrea Sandeman, Hamish 2021-01-01 https://doi.org/10.4138/atlgeol.2021.010 http://id.erudit.org/iderudit/1082236ar en eng Atlantic Geoscience Society Érudit doi:10.4138/atlgeol.2021.010 10670/1.fnrh1l http://id.erudit.org/iderudit/1082236ar other Atlantic Geology: Journal of the Atlantic Geoscience Society / Atlantic Geology: Revue de la Société Géoscientifique de l'Atlantique geo envir Text https://vocabularies.coar-repositories.org/resource_types/c_18cf/ 2021 fttriple https://doi.org/10.4138/atlgeol.2021.010 2023-01-22T16:49:12Z Volcanic rocks of the Ediacaran Musgravetown Group on Bonavista Peninsula, Avalon terrane, Newfoundland, include basal ca. 600 Ma calc-alkaline basalt succeeded by continental tholeiite and alkaline rhyolite of the ca. 592 Ma Plate Cove volcanic belt (Bull Arm Formation), indicating a change from subduction-related to extensionrelated tectonic regimes during that interval. Alkalic basalts on northeastern (Dam Pond area) and southwestern (British Harbour area) Bonavista Peninsula occur below and above, respectively, the ca. 580 Ma glacial Trinity facies. Dam Pond basalt occurs in a structural dome intercalated with and flanked by fine-grained, siliciclastic deposits (Big Head Formation) overlain by Trinity facies. The British Harbour basalt occurs above the Trinity facies, in an upward- coarsening sandstone sequence (Rocky Harbour Formation) overlain by red beds of the Crown Hill Formation (uppermost Musgravetown Group). The Rocky Harbour and Big Head formations are likely stratigraphically interfingered proximal and distal deposits, respectively, derived from erosion of the Bull Arm Formation and older Avalonian assemblages.The Big Head basalts have lower SiO2, Zr, FeOT, P2O5, TiO2 and higher Mg#, Cr, V, Co and Ni contents, and are therefore more primitive than the more FeOT-, TiO2-, and P2O5-rich British Harbour basalts. Large-ionlithophile and rare-earth-element concentrations and ratios indicate that both suites originated from low degree partial melts of deep, weakly garnet-bearing, undepleted asthenospheric peridotite sources, with magma conduits likely focused along regional extensional faults. The protracted and episodic extension-related volcanic activity is consistent with a geodynamic setting that evolved from a mature arc into extensional basins with slowly waning magmatism, possibly involving slab rollback and delamination followed by magmatic underplating. The duration and variation of both volcanism and sedimentation indicate that the Musgravetown Group should be elevated to a Supergroup in order ... Text Newfoundland Unknown Big Head ENVELOPE(-55.081,-55.081,49.517,49.517) Canada Dam Pond ENVELOPE(-56.098,-56.098,49.767,49.767) Rocky Harbour ENVELOPE(-57.932,-57.932,49.583,49.583) Atlantic Geology 57 207 234 |
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geo envir Mills, Andrea Sandeman, Hamish Lithostratigraphy and lithogeochemistry of Ediacaran alkaline basaltic rocks of the Musgravetown Group, Bonavista Peninsula, northeastern Newfoundland, Canada: an extensional volcanogenic basin in the type-Avalon terrane |
topic_facet |
geo envir |
description |
Volcanic rocks of the Ediacaran Musgravetown Group on Bonavista Peninsula, Avalon terrane, Newfoundland, include basal ca. 600 Ma calc-alkaline basalt succeeded by continental tholeiite and alkaline rhyolite of the ca. 592 Ma Plate Cove volcanic belt (Bull Arm Formation), indicating a change from subduction-related to extensionrelated tectonic regimes during that interval. Alkalic basalts on northeastern (Dam Pond area) and southwestern (British Harbour area) Bonavista Peninsula occur below and above, respectively, the ca. 580 Ma glacial Trinity facies. Dam Pond basalt occurs in a structural dome intercalated with and flanked by fine-grained, siliciclastic deposits (Big Head Formation) overlain by Trinity facies. The British Harbour basalt occurs above the Trinity facies, in an upward- coarsening sandstone sequence (Rocky Harbour Formation) overlain by red beds of the Crown Hill Formation (uppermost Musgravetown Group). The Rocky Harbour and Big Head formations are likely stratigraphically interfingered proximal and distal deposits, respectively, derived from erosion of the Bull Arm Formation and older Avalonian assemblages.The Big Head basalts have lower SiO2, Zr, FeOT, P2O5, TiO2 and higher Mg#, Cr, V, Co and Ni contents, and are therefore more primitive than the more FeOT-, TiO2-, and P2O5-rich British Harbour basalts. Large-ionlithophile and rare-earth-element concentrations and ratios indicate that both suites originated from low degree partial melts of deep, weakly garnet-bearing, undepleted asthenospheric peridotite sources, with magma conduits likely focused along regional extensional faults. The protracted and episodic extension-related volcanic activity is consistent with a geodynamic setting that evolved from a mature arc into extensional basins with slowly waning magmatism, possibly involving slab rollback and delamination followed by magmatic underplating. The duration and variation of both volcanism and sedimentation indicate that the Musgravetown Group should be elevated to a Supergroup in order ... |
format |
Text |
author |
Mills, Andrea Sandeman, Hamish |
author_facet |
Mills, Andrea Sandeman, Hamish |
author_sort |
Mills, Andrea |
title |
Lithostratigraphy and lithogeochemistry of Ediacaran alkaline basaltic rocks of the Musgravetown Group, Bonavista Peninsula, northeastern Newfoundland, Canada: an extensional volcanogenic basin in the type-Avalon terrane |
title_short |
Lithostratigraphy and lithogeochemistry of Ediacaran alkaline basaltic rocks of the Musgravetown Group, Bonavista Peninsula, northeastern Newfoundland, Canada: an extensional volcanogenic basin in the type-Avalon terrane |
title_full |
Lithostratigraphy and lithogeochemistry of Ediacaran alkaline basaltic rocks of the Musgravetown Group, Bonavista Peninsula, northeastern Newfoundland, Canada: an extensional volcanogenic basin in the type-Avalon terrane |
title_fullStr |
Lithostratigraphy and lithogeochemistry of Ediacaran alkaline basaltic rocks of the Musgravetown Group, Bonavista Peninsula, northeastern Newfoundland, Canada: an extensional volcanogenic basin in the type-Avalon terrane |
title_full_unstemmed |
Lithostratigraphy and lithogeochemistry of Ediacaran alkaline basaltic rocks of the Musgravetown Group, Bonavista Peninsula, northeastern Newfoundland, Canada: an extensional volcanogenic basin in the type-Avalon terrane |
title_sort |
lithostratigraphy and lithogeochemistry of ediacaran alkaline basaltic rocks of the musgravetown group, bonavista peninsula, northeastern newfoundland, canada: an extensional volcanogenic basin in the type-avalon terrane |
publisher |
Atlantic Geoscience Society |
publishDate |
2021 |
url |
https://doi.org/10.4138/atlgeol.2021.010 http://id.erudit.org/iderudit/1082236ar |
long_lat |
ENVELOPE(-55.081,-55.081,49.517,49.517) ENVELOPE(-56.098,-56.098,49.767,49.767) ENVELOPE(-57.932,-57.932,49.583,49.583) |
geographic |
Big Head Canada Dam Pond Rocky Harbour |
geographic_facet |
Big Head Canada Dam Pond Rocky Harbour |
genre |
Newfoundland |
genre_facet |
Newfoundland |
op_source |
Atlantic Geology: Journal of the Atlantic Geoscience Society / Atlantic Geology: Revue de la Société Géoscientifique de l'Atlantique |
op_relation |
doi:10.4138/atlgeol.2021.010 10670/1.fnrh1l http://id.erudit.org/iderudit/1082236ar |
op_rights |
other |
op_doi |
https://doi.org/10.4138/atlgeol.2021.010 |
container_title |
Atlantic Geology |
container_volume |
57 |
container_start_page |
207 |
op_container_end_page |
234 |
_version_ |
1766108288555941888 |