Discovery of diamond in the Tromsø Nappe, Scandinavian Caledonides (N. Norway)
Abstract We report the first finding of diamond in crustal rocks from the Tromsø Nappe of the North Norwegian Caledonides. Diamond occurs in situ as inclusions in garnet from gneiss at Tønsvika near Tromsø. The rock is composed essentially of garnet, biotite, white mica, quartz and plagioclase, mino...
Published in: | Journal of Metamorphic Geology |
---|---|
Main Authors: | , , , , , |
Other Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Wiley
2013
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1111/jmg.12040 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fjmg.12040 https://onlinelibrary.wiley.com/doi/pdf/10.1111/jmg.12040 |
id |
crwiley:10.1111/jmg.12040 |
---|---|
record_format |
openpolar |
spelling |
crwiley:10.1111/jmg.12040 2024-09-15T18:39:21+00:00 Discovery of diamond in the Tromsø Nappe, Scandinavian Caledonides (N. Norway) Janák, M. Krogh Ravna, E. J. Kullerud, K. Yoshida, K. Milovský, R. Hirajima, T. Slovak Research and Development Agency Slovak Scientific Grant Agency VEGA Agency of the Ministry of Education, Science, Research and Sport of the Slovak Republic for the Structural Funds of EU 2013 http://dx.doi.org/10.1111/jmg.12040 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fjmg.12040 https://onlinelibrary.wiley.com/doi/pdf/10.1111/jmg.12040 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Journal of Metamorphic Geology volume 31, issue 6, page 691-703 ISSN 0263-4929 1525-1314 journal-article 2013 crwiley https://doi.org/10.1111/jmg.12040 2024-07-25T04:21:03Z Abstract We report the first finding of diamond in crustal rocks from the Tromsø Nappe of the North Norwegian Caledonides. Diamond occurs in situ as inclusions in garnet from gneiss at Tønsvika near Tromsø. The rock is composed essentially of garnet, biotite, white mica, quartz and plagioclase, minor constituents include kyanite, zoisite, rutile, tourmaline, amphibole, zircon, apatite and carbonates (magnesite, dolomite, calcite). The microdiamond, identified by micro‐Raman spectroscopy, is cuboidal to octahedral in shape and ranges from 5 to 50 μ m in diameter. The diamond occurs as single grains and as composite diamond + carbonate inclusions. Diamond vibration bands show a downshift from 1 332 to 1 325 cm −1 , the majority of Raman peaks are centred between 1 332 and 1 330 cm −1 and all peaks exhibit a full width at half maximum between 3 and 5 cm −1 . Several spectra show Raman bands typical for disordered and ordered graphite (sp 2 ‐bonded carbon) indicating partial transformation of diamond to graphite. The calculated peak P–T conditions for the diamond‐bearing sample are 3.5 ± 0.5 GPa and 770 ± 50 °C. Metamorphic diamond found in situ in crustal rocks of the Tromsø Nappe thus provides unequivocal evidence for ultrahigh pressure metamorphism in this allochthonous unit of the Scandinavian Caledonides. Deep continental subduction, most probably in the Late Ordovician and shortly before or during the initial collision between Baltica and Laurentia, was required to stabilize the diamond at UHP conditions. Article in Journal/Newspaper Tromsø Wiley Online Library Journal of Metamorphic Geology 31 6 691 703 |
institution |
Open Polar |
collection |
Wiley Online Library |
op_collection_id |
crwiley |
language |
English |
description |
Abstract We report the first finding of diamond in crustal rocks from the Tromsø Nappe of the North Norwegian Caledonides. Diamond occurs in situ as inclusions in garnet from gneiss at Tønsvika near Tromsø. The rock is composed essentially of garnet, biotite, white mica, quartz and plagioclase, minor constituents include kyanite, zoisite, rutile, tourmaline, amphibole, zircon, apatite and carbonates (magnesite, dolomite, calcite). The microdiamond, identified by micro‐Raman spectroscopy, is cuboidal to octahedral in shape and ranges from 5 to 50 μ m in diameter. The diamond occurs as single grains and as composite diamond + carbonate inclusions. Diamond vibration bands show a downshift from 1 332 to 1 325 cm −1 , the majority of Raman peaks are centred between 1 332 and 1 330 cm −1 and all peaks exhibit a full width at half maximum between 3 and 5 cm −1 . Several spectra show Raman bands typical for disordered and ordered graphite (sp 2 ‐bonded carbon) indicating partial transformation of diamond to graphite. The calculated peak P–T conditions for the diamond‐bearing sample are 3.5 ± 0.5 GPa and 770 ± 50 °C. Metamorphic diamond found in situ in crustal rocks of the Tromsø Nappe thus provides unequivocal evidence for ultrahigh pressure metamorphism in this allochthonous unit of the Scandinavian Caledonides. Deep continental subduction, most probably in the Late Ordovician and shortly before or during the initial collision between Baltica and Laurentia, was required to stabilize the diamond at UHP conditions. |
author2 |
Slovak Research and Development Agency Slovak Scientific Grant Agency VEGA Agency of the Ministry of Education, Science, Research and Sport of the Slovak Republic for the Structural Funds of EU |
format |
Article in Journal/Newspaper |
author |
Janák, M. Krogh Ravna, E. J. Kullerud, K. Yoshida, K. Milovský, R. Hirajima, T. |
spellingShingle |
Janák, M. Krogh Ravna, E. J. Kullerud, K. Yoshida, K. Milovský, R. Hirajima, T. Discovery of diamond in the Tromsø Nappe, Scandinavian Caledonides (N. Norway) |
author_facet |
Janák, M. Krogh Ravna, E. J. Kullerud, K. Yoshida, K. Milovský, R. Hirajima, T. |
author_sort |
Janák, M. |
title |
Discovery of diamond in the Tromsø Nappe, Scandinavian Caledonides (N. Norway) |
title_short |
Discovery of diamond in the Tromsø Nappe, Scandinavian Caledonides (N. Norway) |
title_full |
Discovery of diamond in the Tromsø Nappe, Scandinavian Caledonides (N. Norway) |
title_fullStr |
Discovery of diamond in the Tromsø Nappe, Scandinavian Caledonides (N. Norway) |
title_full_unstemmed |
Discovery of diamond in the Tromsø Nappe, Scandinavian Caledonides (N. Norway) |
title_sort |
discovery of diamond in the tromsø nappe, scandinavian caledonides (n. norway) |
publisher |
Wiley |
publishDate |
2013 |
url |
http://dx.doi.org/10.1111/jmg.12040 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fjmg.12040 https://onlinelibrary.wiley.com/doi/pdf/10.1111/jmg.12040 |
genre |
Tromsø |
genre_facet |
Tromsø |
op_source |
Journal of Metamorphic Geology volume 31, issue 6, page 691-703 ISSN 0263-4929 1525-1314 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1111/jmg.12040 |
container_title |
Journal of Metamorphic Geology |
container_volume |
31 |
container_issue |
6 |
container_start_page |
691 |
op_container_end_page |
703 |
_version_ |
1810483736944312320 |