Magma Mushes of the Fogo Island Batholith: a Study of Magmatic Processes at Multiple Scales
Abstract This field, petrographic, and geochemical study examines mingling of compositionally similar rocks at multiple scales. Evidence of complex magma interaction in a multi-component crystal mush reservoir is preserved within the Wild Unit, located along the NE shoreline of Fogo Island, Newfound...
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Oxford University Press (OUP)
2020
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Online Access: | http://dx.doi.org/10.1093/petrology/egaa097 http://academic.oup.com/petrology/advance-article-pdf/doi/10.1093/petrology/egaa097/34042306/egaa097.pdf http://academic.oup.com/petrology/article-pdf/61/10/egaa097/37165924/egaa097.pdf |
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croxfordunivpr:10.1093/petrology/egaa097 2024-04-28T08:28:55+00:00 Magma Mushes of the Fogo Island Batholith: a Study of Magmatic Processes at Multiple Scales Graham, B Dunning, G Leitch, A M Hibernia Geophysics Fund Memorial University 2020 http://dx.doi.org/10.1093/petrology/egaa097 http://academic.oup.com/petrology/advance-article-pdf/doi/10.1093/petrology/egaa097/34042306/egaa097.pdf http://academic.oup.com/petrology/article-pdf/61/10/egaa097/37165924/egaa097.pdf en eng Oxford University Press (OUP) https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model Journal of Petrology volume 61, issue 10 ISSN 1460-2415 Geochemistry and Petrology Geophysics journal-article 2020 croxfordunivpr https://doi.org/10.1093/petrology/egaa097 2024-04-09T07:56:29Z Abstract This field, petrographic, and geochemical study examines mingling of compositionally similar rocks at multiple scales. Evidence of complex magma interaction in a multi-component crystal mush reservoir is preserved within the Wild Unit, located along the NE shoreline of Fogo Island, Newfoundland and Labrador, Canada. The irregular contacts and lack of chilled margins between units, the back-intrusion of younger units by older units, the similar composition of units, and an overlap in U–Pb zircon ages suggest that all units interacted as viscous crystal mushes at similar temperatures in the shallow crust. Abundant rounded to ellipsoidal magmatic enclaves, of which there are at least three populations based on composition and crystallinity, appear to represent separate magmas that were entrained either as earlier mush material or crystal-poor intrusions that experienced break-up. Evidence of changes in liquid environment at deeper levels is preserved both in the field and at the mineral scale, where it is highlighted by abrupt compositional spikes in traverses across early forming plagioclase and pyroxene crystals. Heterogeneity in textures and composition of both major minerals (plagioclase and pyroxene) and an accessory mineral (zircon) point to processes such as crystal exchange and capture affecting tonalite crystal mushes, magmatic enclaves, and other intrusions in the study area earlier in their histories at deeper levels. Article in Journal/Newspaper Newfoundland Oxford University Press Journal of Petrology 61 10 |
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Open Polar |
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Oxford University Press |
op_collection_id |
croxfordunivpr |
language |
English |
topic |
Geochemistry and Petrology Geophysics |
spellingShingle |
Geochemistry and Petrology Geophysics Graham, B Dunning, G Leitch, A M Magma Mushes of the Fogo Island Batholith: a Study of Magmatic Processes at Multiple Scales |
topic_facet |
Geochemistry and Petrology Geophysics |
description |
Abstract This field, petrographic, and geochemical study examines mingling of compositionally similar rocks at multiple scales. Evidence of complex magma interaction in a multi-component crystal mush reservoir is preserved within the Wild Unit, located along the NE shoreline of Fogo Island, Newfoundland and Labrador, Canada. The irregular contacts and lack of chilled margins between units, the back-intrusion of younger units by older units, the similar composition of units, and an overlap in U–Pb zircon ages suggest that all units interacted as viscous crystal mushes at similar temperatures in the shallow crust. Abundant rounded to ellipsoidal magmatic enclaves, of which there are at least three populations based on composition and crystallinity, appear to represent separate magmas that were entrained either as earlier mush material or crystal-poor intrusions that experienced break-up. Evidence of changes in liquid environment at deeper levels is preserved both in the field and at the mineral scale, where it is highlighted by abrupt compositional spikes in traverses across early forming plagioclase and pyroxene crystals. Heterogeneity in textures and composition of both major minerals (plagioclase and pyroxene) and an accessory mineral (zircon) point to processes such as crystal exchange and capture affecting tonalite crystal mushes, magmatic enclaves, and other intrusions in the study area earlier in their histories at deeper levels. |
author2 |
Hibernia Geophysics Fund Memorial University |
format |
Article in Journal/Newspaper |
author |
Graham, B Dunning, G Leitch, A M |
author_facet |
Graham, B Dunning, G Leitch, A M |
author_sort |
Graham, B |
title |
Magma Mushes of the Fogo Island Batholith: a Study of Magmatic Processes at Multiple Scales |
title_short |
Magma Mushes of the Fogo Island Batholith: a Study of Magmatic Processes at Multiple Scales |
title_full |
Magma Mushes of the Fogo Island Batholith: a Study of Magmatic Processes at Multiple Scales |
title_fullStr |
Magma Mushes of the Fogo Island Batholith: a Study of Magmatic Processes at Multiple Scales |
title_full_unstemmed |
Magma Mushes of the Fogo Island Batholith: a Study of Magmatic Processes at Multiple Scales |
title_sort |
magma mushes of the fogo island batholith: a study of magmatic processes at multiple scales |
publisher |
Oxford University Press (OUP) |
publishDate |
2020 |
url |
http://dx.doi.org/10.1093/petrology/egaa097 http://academic.oup.com/petrology/advance-article-pdf/doi/10.1093/petrology/egaa097/34042306/egaa097.pdf http://academic.oup.com/petrology/article-pdf/61/10/egaa097/37165924/egaa097.pdf |
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Newfoundland |
genre_facet |
Newfoundland |
op_source |
Journal of Petrology volume 61, issue 10 ISSN 1460-2415 |
op_rights |
https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model |
op_doi |
https://doi.org/10.1093/petrology/egaa097 |
container_title |
Journal of Petrology |
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61 |
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10 |
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1797587294292541440 |