Mingling of multiple crystals mushes in the Fogo batholith
This field, petrographic, and geochemical study examines mingling of compositionally similar rocks at multiple scales. Evidence of complex magma mingling in a multi-component crystal mush reservoir is preserved at Wild Cove East, located along the northeast shoreline of Fogo Island, Newfoundland. Th...
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Memorial University of Newfoundland
2017
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Online Access: | https://research.library.mun.ca/13221/ https://research.library.mun.ca/13221/1/thesis.pdf |
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ftmemorialuniv:oai:research.library.mun.ca:13221 2023-10-01T03:57:37+02:00 Mingling of multiple crystals mushes in the Fogo batholith Graham, Benjamin 2017-10 application/pdf https://research.library.mun.ca/13221/ https://research.library.mun.ca/13221/1/thesis.pdf en eng Memorial University of Newfoundland https://research.library.mun.ca/13221/1/thesis.pdf Graham, Benjamin <https://research.library.mun.ca/view/creator_az/Graham=3ABenjamin=3A=3A.html> (2017) Mingling of multiple crystals mushes in the Fogo batholith. Masters thesis, Memorial University of Newfoundland. thesis_license Thesis NonPeerReviewed 2017 ftmemorialuniv 2023-09-03T06:49:08Z This field, petrographic, and geochemical study examines mingling of compositionally similar rocks at multiple scales. Evidence of complex magma mingling in a multi-component crystal mush reservoir is preserved at Wild Cove East, located along the northeast shoreline of Fogo Island, Newfoundland. 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 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 different 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 at depth. Evidence of exchange of liquid 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 minerals such as plagioclase and pyroxene. Heterogeneity in textures and composition of both major minerals (plagioclase and pyroxene) and an accessory mineral (zircon) suggest processes such as crystal exchange and capture affected mush host rocks, enclaves, and other intrusions in the study area earlier in their histories at deeper levels. Thesis Newfoundland Memorial University of Newfoundland: Research Repository Fogo ENVELOPE(-54.281,-54.281,49.717,49.717) Fogo Island ENVELOPE(-54.165,-54.165,49.667,49.667) Wild Cove ENVELOPE(-54.781,-54.781,49.667,49.667) |
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Memorial University of Newfoundland: Research Repository |
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ftmemorialuniv |
language |
English |
description |
This field, petrographic, and geochemical study examines mingling of compositionally similar rocks at multiple scales. Evidence of complex magma mingling in a multi-component crystal mush reservoir is preserved at Wild Cove East, located along the northeast shoreline of Fogo Island, Newfoundland. 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 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 different 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 at depth. Evidence of exchange of liquid 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 minerals such as plagioclase and pyroxene. Heterogeneity in textures and composition of both major minerals (plagioclase and pyroxene) and an accessory mineral (zircon) suggest processes such as crystal exchange and capture affected mush host rocks, enclaves, and other intrusions in the study area earlier in their histories at deeper levels. |
format |
Thesis |
author |
Graham, Benjamin |
spellingShingle |
Graham, Benjamin Mingling of multiple crystals mushes in the Fogo batholith |
author_facet |
Graham, Benjamin |
author_sort |
Graham, Benjamin |
title |
Mingling of multiple crystals mushes in the Fogo batholith |
title_short |
Mingling of multiple crystals mushes in the Fogo batholith |
title_full |
Mingling of multiple crystals mushes in the Fogo batholith |
title_fullStr |
Mingling of multiple crystals mushes in the Fogo batholith |
title_full_unstemmed |
Mingling of multiple crystals mushes in the Fogo batholith |
title_sort |
mingling of multiple crystals mushes in the fogo batholith |
publisher |
Memorial University of Newfoundland |
publishDate |
2017 |
url |
https://research.library.mun.ca/13221/ https://research.library.mun.ca/13221/1/thesis.pdf |
long_lat |
ENVELOPE(-54.281,-54.281,49.717,49.717) ENVELOPE(-54.165,-54.165,49.667,49.667) ENVELOPE(-54.781,-54.781,49.667,49.667) |
geographic |
Fogo Fogo Island Wild Cove |
geographic_facet |
Fogo Fogo Island Wild Cove |
genre |
Newfoundland |
genre_facet |
Newfoundland |
op_relation |
https://research.library.mun.ca/13221/1/thesis.pdf Graham, Benjamin <https://research.library.mun.ca/view/creator_az/Graham=3ABenjamin=3A=3A.html> (2017) Mingling of multiple crystals mushes in the Fogo batholith. Masters thesis, Memorial University of Newfoundland. |
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thesis_license |
_version_ |
1778529413961351168 |