Titanite petrochronology linked to phase equilibrium modelling constrains tectono-thermal events in the Akia Terrane, West Greenland
The Mesoarchean Akia Terrane in West Greenland contains a detailed magmatic and metamorphic mineral growth record from 3.2 Ga to at least c. 2.5 Ga. This time span makes this region an important case study in the quest to track secular changes in geodynamic style which may ultimately inform on the d...
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2020
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Online Access: | https://research-portal.st-andrews.ac.uk/en/researchoutput/titanite-petrochronology-linked-to-phase-equilibrium-modelling-constrains-tectonothermal-events-in-the-akia-terrane-west-greenland(ccbde835-e339-4ab2-b129-30206a730a2f).html https://doi.org/10.1016/j.chemgeo.2020.119467 https://research-repository.st-andrews.ac.uk/bitstream/10023/19327/1/Kirkland_2020_CG_Titanite_CC.pdf |
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ftunstandrewcris:oai:research-portal.st-andrews.ac.uk:publications/ccbde835-e339-4ab2-b129-30206a730a2f 2024-09-09T19:43:19+00:00 Titanite petrochronology linked to phase equilibrium modelling constrains tectono-thermal events in the Akia Terrane, West Greenland Kirkland, C.L. Yakymchuk, C. Gardiner, N. J. Szilas, K. Hollis, J. Olierook, H. Steenfelt, A. 2020-03-20 application/pdf https://research-portal.st-andrews.ac.uk/en/researchoutput/titanite-petrochronology-linked-to-phase-equilibrium-modelling-constrains-tectonothermal-events-in-the-akia-terrane-west-greenland(ccbde835-e339-4ab2-b129-30206a730a2f).html https://doi.org/10.1016/j.chemgeo.2020.119467 https://research-repository.st-andrews.ac.uk/bitstream/10023/19327/1/Kirkland_2020_CG_Titanite_CC.pdf eng eng https://research-portal.st-andrews.ac.uk/en/researchoutput/titanite-petrochronology-linked-to-phase-equilibrium-modelling-constrains-tectonothermal-events-in-the-akia-terrane-west-greenland(ccbde835-e339-4ab2-b129-30206a730a2f).html info:eu-repo/semantics/openAccess Kirkland , C L , Yakymchuk , C , Gardiner , N J , Szilas , K , Hollis , J , Olierook , H & Steenfelt , A 2020 , ' Titanite petrochronology linked to phase equilibrium modelling constrains tectono-thermal events in the Akia Terrane, West Greenland ' , Chemical Geology , vol. 536 , 119467 . https://doi.org/10.1016/j.chemgeo.2020.119467 Titanite Geochronology Phase equilibrium Ti-in-zircon Petrochronology article 2020 ftunstandrewcris https://doi.org/10.1016/j.chemgeo.2020.119467 2024-07-17T23:33:27Z The Mesoarchean Akia Terrane in West Greenland contains a detailed magmatic and metamorphic mineral growth record from 3.2 Ga to at least c. 2.5 Ga. This time span makes this region an important case study in the quest to track secular changes in geodynamic style which may ultimately inform on the development of plate tectonics as a globally linked system of lateral rigid plate motions. The common accessory mineral titanite has recently become recognised as a powerful high temperature geochronometer whose chemistry may chart the thermal conditions of its growth. Furthermore, titanite offers the potential to record the time-temperature history of mafic lithologies, which may lack zircon. Although titanite suffers from higher levels of common Pb than many other UPb chronometers, we show how measurement of 207 Pb/ 206 Pb in texturally coeval biotite may assist in the characterization of the appropriate common Pb composition in titanite. Titanite extracted from two samples of mafic gneisses from the Akia Terrane both yield UPb ages of c. 2.54 Ga. Although coeval, their chemistry implies growth under two distinctly different processes. In one case, the titanite has elevated total REE, high Th/U and grew from an in-situ partial melt, consistent with an identical date to granite dyke zircon. In contrast, the second titanite sample contains greater common Pb, lower total REE, lower Th/U, and grew from dominantly hydrothermal fluids. Zr-in-titanite thermometry for partial melt-derived titanite, with activities constrained by phase equilibrium modelling, indicates maxima of c. 690 °C. Elsewhere in the Akia Terrane, coeval metamorphism linked to growth of hydrothermal titanite is estimated at temperatures of c. 670 °C. These new results when coupled with existing findings indicate punctuated, repeated metamorphic events in the Akia Terrane, in which high temperature conditions (re)occurred at least three times between 3.0 and 2.5 Ga, but crucially changed in style across a c. 3.0 Ga change point. We interpret this change ... Article in Journal/Newspaper Greenland University of St Andrews: Research Portal Greenland Chemical Geology 536 119467 |
institution |
Open Polar |
collection |
University of St Andrews: Research Portal |
op_collection_id |
ftunstandrewcris |
language |
English |
topic |
Titanite Geochronology Phase equilibrium Ti-in-zircon Petrochronology |
spellingShingle |
Titanite Geochronology Phase equilibrium Ti-in-zircon Petrochronology Kirkland, C.L. Yakymchuk, C. Gardiner, N. J. Szilas, K. Hollis, J. Olierook, H. Steenfelt, A. Titanite petrochronology linked to phase equilibrium modelling constrains tectono-thermal events in the Akia Terrane, West Greenland |
topic_facet |
Titanite Geochronology Phase equilibrium Ti-in-zircon Petrochronology |
description |
The Mesoarchean Akia Terrane in West Greenland contains a detailed magmatic and metamorphic mineral growth record from 3.2 Ga to at least c. 2.5 Ga. This time span makes this region an important case study in the quest to track secular changes in geodynamic style which may ultimately inform on the development of plate tectonics as a globally linked system of lateral rigid plate motions. The common accessory mineral titanite has recently become recognised as a powerful high temperature geochronometer whose chemistry may chart the thermal conditions of its growth. Furthermore, titanite offers the potential to record the time-temperature history of mafic lithologies, which may lack zircon. Although titanite suffers from higher levels of common Pb than many other UPb chronometers, we show how measurement of 207 Pb/ 206 Pb in texturally coeval biotite may assist in the characterization of the appropriate common Pb composition in titanite. Titanite extracted from two samples of mafic gneisses from the Akia Terrane both yield UPb ages of c. 2.54 Ga. Although coeval, their chemistry implies growth under two distinctly different processes. In one case, the titanite has elevated total REE, high Th/U and grew from an in-situ partial melt, consistent with an identical date to granite dyke zircon. In contrast, the second titanite sample contains greater common Pb, lower total REE, lower Th/U, and grew from dominantly hydrothermal fluids. Zr-in-titanite thermometry for partial melt-derived titanite, with activities constrained by phase equilibrium modelling, indicates maxima of c. 690 °C. Elsewhere in the Akia Terrane, coeval metamorphism linked to growth of hydrothermal titanite is estimated at temperatures of c. 670 °C. These new results when coupled with existing findings indicate punctuated, repeated metamorphic events in the Akia Terrane, in which high temperature conditions (re)occurred at least three times between 3.0 and 2.5 Ga, but crucially changed in style across a c. 3.0 Ga change point. We interpret this change ... |
format |
Article in Journal/Newspaper |
author |
Kirkland, C.L. Yakymchuk, C. Gardiner, N. J. Szilas, K. Hollis, J. Olierook, H. Steenfelt, A. |
author_facet |
Kirkland, C.L. Yakymchuk, C. Gardiner, N. J. Szilas, K. Hollis, J. Olierook, H. Steenfelt, A. |
author_sort |
Kirkland, C.L. |
title |
Titanite petrochronology linked to phase equilibrium modelling constrains tectono-thermal events in the Akia Terrane, West Greenland |
title_short |
Titanite petrochronology linked to phase equilibrium modelling constrains tectono-thermal events in the Akia Terrane, West Greenland |
title_full |
Titanite petrochronology linked to phase equilibrium modelling constrains tectono-thermal events in the Akia Terrane, West Greenland |
title_fullStr |
Titanite petrochronology linked to phase equilibrium modelling constrains tectono-thermal events in the Akia Terrane, West Greenland |
title_full_unstemmed |
Titanite petrochronology linked to phase equilibrium modelling constrains tectono-thermal events in the Akia Terrane, West Greenland |
title_sort |
titanite petrochronology linked to phase equilibrium modelling constrains tectono-thermal events in the akia terrane, west greenland |
publishDate |
2020 |
url |
https://research-portal.st-andrews.ac.uk/en/researchoutput/titanite-petrochronology-linked-to-phase-equilibrium-modelling-constrains-tectonothermal-events-in-the-akia-terrane-west-greenland(ccbde835-e339-4ab2-b129-30206a730a2f).html https://doi.org/10.1016/j.chemgeo.2020.119467 https://research-repository.st-andrews.ac.uk/bitstream/10023/19327/1/Kirkland_2020_CG_Titanite_CC.pdf |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland |
genre_facet |
Greenland |
op_source |
Kirkland , C L , Yakymchuk , C , Gardiner , N J , Szilas , K , Hollis , J , Olierook , H & Steenfelt , A 2020 , ' Titanite petrochronology linked to phase equilibrium modelling constrains tectono-thermal events in the Akia Terrane, West Greenland ' , Chemical Geology , vol. 536 , 119467 . https://doi.org/10.1016/j.chemgeo.2020.119467 |
op_relation |
https://research-portal.st-andrews.ac.uk/en/researchoutput/titanite-petrochronology-linked-to-phase-equilibrium-modelling-constrains-tectonothermal-events-in-the-akia-terrane-west-greenland(ccbde835-e339-4ab2-b129-30206a730a2f).html |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1016/j.chemgeo.2020.119467 |
container_title |
Chemical Geology |
container_volume |
536 |
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119467 |
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