Sedimentary recycling in arc magmas:geochemical and U–Pb–Hf–O constraints on the Mesoproterozoic Suldal Arc, SW Norway
The Hardangervidda-Rogaland Block within southwest Norway is host to ~1.52 to 1.48 Ga continental building and variable reworking during the ~1.1 to 0.9 Ga Sveconorwegian orogeny. Due to the lack of geochronological and geochemical data, the timing and tectonic setting of early Mesoproterozoic magma...
Published in: | Contributions to Mineralogy and Petrology |
---|---|
Main Authors: | , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2013
|
Subjects: | |
Online Access: | https://doi.org/10.1007/s00410-012-0820-y https://researchportal.port.ac.uk/portal/en/publications/sedimentary-recycling-in-arc-magmas(b082671f-48f3-4ecb-aa3a-288e289f1e40).html http://link.springer.com/10.1007/s00410-012-0820-y |
id |
ftunivportsmpubl:oai:researchportal.port.ac.uk:publications/b082671f-48f3-4ecb-aa3a-288e289f1e40 |
---|---|
record_format |
openpolar |
spelling |
ftunivportsmpubl:oai:researchportal.port.ac.uk:publications/b082671f-48f3-4ecb-aa3a-288e289f1e40 2023-05-15T16:12:19+02:00 Sedimentary recycling in arc magmas:geochemical and U–Pb–Hf–O constraints on the Mesoproterozoic Suldal Arc, SW Norway Roberts, Nick M. W. Slagstad, Trond Parrish, Randall R. Norry, Michael J. Marker, Mogens Horstwood, Matthew S. A. 2013-03-01 https://doi.org/10.1007/s00410-012-0820-y https://researchportal.port.ac.uk/portal/en/publications/sedimentary-recycling-in-arc-magmas(b082671f-48f3-4ecb-aa3a-288e289f1e40).html http://link.springer.com/10.1007/s00410-012-0820-y eng eng info:eu-repo/semantics/restrictedAccess Roberts , N M W , Slagstad , T , Parrish , R R , Norry , M J , Marker , M & Horstwood , M S A 2013 , ' Sedimentary recycling in arc magmas : geochemical and U–Pb–Hf–O constraints on the Mesoproterozoic Suldal Arc, SW Norway ' Contributions to Mineralogy and Petrology , vol 165 , no. 3 , pp. 507-523 . DOI:10.1007/s00410-012-0820-y /dk/atira/pure/core/subjects/earthsci Earth Sciences article 2013 ftunivportsmpubl https://doi.org/10.1007/s00410-012-0820-y 2017-09-28T19:36:02Z The Hardangervidda-Rogaland Block within southwest Norway is host to ~1.52 to 1.48 Ga continental building and variable reworking during the ~1.1 to 0.9 Ga Sveconorwegian orogeny. Due to the lack of geochronological and geochemical data, the timing and tectonic setting of early Mesoproterozoic magmatism has long been ambiguous. This paper presents zircon U–Pb–Hf–O isotope data combined with whole-rock geochemistry to address the age and petrogenesis of basement units within the Suldal region, located in the centre of the Hardangervidda-Rogaland Block. The basement comprises variably deformed grey gneisses and granitoids that petrologically and geochemically resemble mature volcanic arc lithologies. U–Pb ages confirm that magmatism occurred from ~1,521 to 1,485 Ma, and conspicuously lack any xenocrystic inheritance of distinctly older crust. Hafnium isotope data range from εHf(initial) +1 to +11, suggesting a rather juvenile magmatic source, but with possible involvement of late Palaeoproterozoic crust. Oxygen isotope data range from mantle-like (δ 18 O ~5 ‰) to elevated (~10 ‰) suggesting involvement of low-temperature altered material (e.g., supracrustal rocks) in the magma source. The Hf–O isotope array is compatible with mixing between mantle-derived material with young low-temperature altered material (oceanic crust/sediments) and older low-temperature altered material (continent-derived sediments). This, combined with a lack of xenoliths and xenocrysts, exposed older crust, AFC trends and S-type geochemistry, all point to mixing within a deep-crustal magma-generation zone. A proposed model comprises accretion of altered oceanic crust and the overlying sediments to a pre-existing continental margin, underthrusting to the magma-generation zone and remobilisation during arc magmatism. The geodynamic setting for this arc magmatism is comparable with that seen in the Phanerozoic (e.g., the Sierra Nevada and Coast Range batholiths), with compositions in the Suldal Sector reaching those of average upper continental crust. As within these younger examples, factors that drive magmatism towards the composition of the average continental crust include the addition of sedimentary material to magma source regions, and delamination of cumulate material. Underthrusting of sedimentary materials and their subsequent involvement in arc magmatism is perhaps a more widespread mechanism involved in continental growth than is currently recognised. Finally, the Suldal Arc magmatism represents a significant juvenile crustal addition to SW Fennoscandia. Article in Journal/Newspaper Fennoscandia University of Portsmouth: Portsmouth Research Portal Norway Contributions to Mineralogy and Petrology 165 3 507 523 |
institution |
Open Polar |
collection |
University of Portsmouth: Portsmouth Research Portal |
op_collection_id |
ftunivportsmpubl |
language |
English |
topic |
/dk/atira/pure/core/subjects/earthsci Earth Sciences |
spellingShingle |
/dk/atira/pure/core/subjects/earthsci Earth Sciences Roberts, Nick M. W. Slagstad, Trond Parrish, Randall R. Norry, Michael J. Marker, Mogens Horstwood, Matthew S. A. Sedimentary recycling in arc magmas:geochemical and U–Pb–Hf–O constraints on the Mesoproterozoic Suldal Arc, SW Norway |
topic_facet |
/dk/atira/pure/core/subjects/earthsci Earth Sciences |
description |
The Hardangervidda-Rogaland Block within southwest Norway is host to ~1.52 to 1.48 Ga continental building and variable reworking during the ~1.1 to 0.9 Ga Sveconorwegian orogeny. Due to the lack of geochronological and geochemical data, the timing and tectonic setting of early Mesoproterozoic magmatism has long been ambiguous. This paper presents zircon U–Pb–Hf–O isotope data combined with whole-rock geochemistry to address the age and petrogenesis of basement units within the Suldal region, located in the centre of the Hardangervidda-Rogaland Block. The basement comprises variably deformed grey gneisses and granitoids that petrologically and geochemically resemble mature volcanic arc lithologies. U–Pb ages confirm that magmatism occurred from ~1,521 to 1,485 Ma, and conspicuously lack any xenocrystic inheritance of distinctly older crust. Hafnium isotope data range from εHf(initial) +1 to +11, suggesting a rather juvenile magmatic source, but with possible involvement of late Palaeoproterozoic crust. Oxygen isotope data range from mantle-like (δ 18 O ~5 ‰) to elevated (~10 ‰) suggesting involvement of low-temperature altered material (e.g., supracrustal rocks) in the magma source. The Hf–O isotope array is compatible with mixing between mantle-derived material with young low-temperature altered material (oceanic crust/sediments) and older low-temperature altered material (continent-derived sediments). This, combined with a lack of xenoliths and xenocrysts, exposed older crust, AFC trends and S-type geochemistry, all point to mixing within a deep-crustal magma-generation zone. A proposed model comprises accretion of altered oceanic crust and the overlying sediments to a pre-existing continental margin, underthrusting to the magma-generation zone and remobilisation during arc magmatism. The geodynamic setting for this arc magmatism is comparable with that seen in the Phanerozoic (e.g., the Sierra Nevada and Coast Range batholiths), with compositions in the Suldal Sector reaching those of average upper continental crust. As within these younger examples, factors that drive magmatism towards the composition of the average continental crust include the addition of sedimentary material to magma source regions, and delamination of cumulate material. Underthrusting of sedimentary materials and their subsequent involvement in arc magmatism is perhaps a more widespread mechanism involved in continental growth than is currently recognised. Finally, the Suldal Arc magmatism represents a significant juvenile crustal addition to SW Fennoscandia. |
format |
Article in Journal/Newspaper |
author |
Roberts, Nick M. W. Slagstad, Trond Parrish, Randall R. Norry, Michael J. Marker, Mogens Horstwood, Matthew S. A. |
author_facet |
Roberts, Nick M. W. Slagstad, Trond Parrish, Randall R. Norry, Michael J. Marker, Mogens Horstwood, Matthew S. A. |
author_sort |
Roberts, Nick M. W. |
title |
Sedimentary recycling in arc magmas:geochemical and U–Pb–Hf–O constraints on the Mesoproterozoic Suldal Arc, SW Norway |
title_short |
Sedimentary recycling in arc magmas:geochemical and U–Pb–Hf–O constraints on the Mesoproterozoic Suldal Arc, SW Norway |
title_full |
Sedimentary recycling in arc magmas:geochemical and U–Pb–Hf–O constraints on the Mesoproterozoic Suldal Arc, SW Norway |
title_fullStr |
Sedimentary recycling in arc magmas:geochemical and U–Pb–Hf–O constraints on the Mesoproterozoic Suldal Arc, SW Norway |
title_full_unstemmed |
Sedimentary recycling in arc magmas:geochemical and U–Pb–Hf–O constraints on the Mesoproterozoic Suldal Arc, SW Norway |
title_sort |
sedimentary recycling in arc magmas:geochemical and u–pb–hf–o constraints on the mesoproterozoic suldal arc, sw norway |
publishDate |
2013 |
url |
https://doi.org/10.1007/s00410-012-0820-y https://researchportal.port.ac.uk/portal/en/publications/sedimentary-recycling-in-arc-magmas(b082671f-48f3-4ecb-aa3a-288e289f1e40).html http://link.springer.com/10.1007/s00410-012-0820-y |
geographic |
Norway |
geographic_facet |
Norway |
genre |
Fennoscandia |
genre_facet |
Fennoscandia |
op_source |
Roberts , N M W , Slagstad , T , Parrish , R R , Norry , M J , Marker , M & Horstwood , M S A 2013 , ' Sedimentary recycling in arc magmas : geochemical and U–Pb–Hf–O constraints on the Mesoproterozoic Suldal Arc, SW Norway ' Contributions to Mineralogy and Petrology , vol 165 , no. 3 , pp. 507-523 . DOI:10.1007/s00410-012-0820-y |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1007/s00410-012-0820-y |
container_title |
Contributions to Mineralogy and Petrology |
container_volume |
165 |
container_issue |
3 |
container_start_page |
507 |
op_container_end_page |
523 |
_version_ |
1765997598649352192 |