East Greenland Caledonides: stratigraphy, structure and geochronology: Reconnaissance Pb-Pb dating of single mineral phases by the step-leaching method: results from the Caledonides of East Greenland
Reconnaissance Pb-Pb step-leaching analyses have been carried out on garnet and kyanite from the Krummedal supracrustal sequence in East Greenland, yielding respectively Neoproterozoic and Caledonian ages. These data support previous analyses suggesting that the Krummedalsupracrustal sequence, wides...
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Geological Survey of Denmark and Greenland
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ftdoajarticles:oai:doaj.org/article:6b211c24f0724df19788fca864792224 2023-05-15T16:03:11+02:00 East Greenland Caledonides: stratigraphy, structure and geochronology: Reconnaissance Pb-Pb dating of single mineral phases by the step-leaching method: results from the Caledonides of East Greenland Thrane, Kristine 2004-12-01T00:00:00Z https://doaj.org/article/6b211c24f0724df19788fca864792224 EN eng Geological Survey of Denmark and Greenland http://www.geus.dk/publications/bull/nr6/nr6_p67-76.pdf https://doaj.org/toc/1604-8156 1604-8156 https://doaj.org/article/6b211c24f0724df19788fca864792224 Geological Survey of Denmark and Greenland Bulletin, Vol 06, Pp 67-76 (2004) Caledonian East Greenland geochronology Neoproterozoic step-leaching Geology QE1-996.5 Geophysics. Cosmic physics QC801-809 article 2004 ftdoajarticles 2022-12-31T09:42:17Z Reconnaissance Pb-Pb step-leaching analyses have been carried out on garnet and kyanite from the Krummedal supracrustal sequence in East Greenland, yielding respectively Neoproterozoic and Caledonian ages. These data support previous analyses suggesting that the Krummedalsupracrustal sequence, widespread in southern parts of the East Greenland Caledonides, was affected by both an early Neoproterozoic and a Caledonian thermal event. Titanite and apatite fractions from the underlying crystalline basement rocks were analysed in order to obtain metamorphic ages, as a contrast and supplement to the numerous existing protolith ages on orthogneisses. The titanite yielded a date of 486 ± 15 Ma which, if interpreted as a true age, is older than the usual range of Caledonian ages in East Greenland. The significance of this date is uncertain, but one possibility is that it reflects extension and subsidence taking place prior toCaledonian collision. The apatite, in contrast, yielded a very young Caledonian date of 392 ± 24 Ma that may reflect the cooling of the basement gneisses to < 500°C subsequent to collision. Article in Journal/Newspaper East Greenland Greenland Geological Survey of Denmark and Greenland Bulletin Directory of Open Access Journals: DOAJ Articles Greenland |
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Directory of Open Access Journals: DOAJ Articles |
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language |
English |
topic |
Caledonian East Greenland geochronology Neoproterozoic step-leaching Geology QE1-996.5 Geophysics. Cosmic physics QC801-809 |
spellingShingle |
Caledonian East Greenland geochronology Neoproterozoic step-leaching Geology QE1-996.5 Geophysics. Cosmic physics QC801-809 Thrane, Kristine East Greenland Caledonides: stratigraphy, structure and geochronology: Reconnaissance Pb-Pb dating of single mineral phases by the step-leaching method: results from the Caledonides of East Greenland |
topic_facet |
Caledonian East Greenland geochronology Neoproterozoic step-leaching Geology QE1-996.5 Geophysics. Cosmic physics QC801-809 |
description |
Reconnaissance Pb-Pb step-leaching analyses have been carried out on garnet and kyanite from the Krummedal supracrustal sequence in East Greenland, yielding respectively Neoproterozoic and Caledonian ages. These data support previous analyses suggesting that the Krummedalsupracrustal sequence, widespread in southern parts of the East Greenland Caledonides, was affected by both an early Neoproterozoic and a Caledonian thermal event. Titanite and apatite fractions from the underlying crystalline basement rocks were analysed in order to obtain metamorphic ages, as a contrast and supplement to the numerous existing protolith ages on orthogneisses. The titanite yielded a date of 486 ± 15 Ma which, if interpreted as a true age, is older than the usual range of Caledonian ages in East Greenland. The significance of this date is uncertain, but one possibility is that it reflects extension and subsidence taking place prior toCaledonian collision. The apatite, in contrast, yielded a very young Caledonian date of 392 ± 24 Ma that may reflect the cooling of the basement gneisses to < 500°C subsequent to collision. |
format |
Article in Journal/Newspaper |
author |
Thrane, Kristine |
author_facet |
Thrane, Kristine |
author_sort |
Thrane, Kristine |
title |
East Greenland Caledonides: stratigraphy, structure and geochronology: Reconnaissance Pb-Pb dating of single mineral phases by the step-leaching method: results from the Caledonides of East Greenland |
title_short |
East Greenland Caledonides: stratigraphy, structure and geochronology: Reconnaissance Pb-Pb dating of single mineral phases by the step-leaching method: results from the Caledonides of East Greenland |
title_full |
East Greenland Caledonides: stratigraphy, structure and geochronology: Reconnaissance Pb-Pb dating of single mineral phases by the step-leaching method: results from the Caledonides of East Greenland |
title_fullStr |
East Greenland Caledonides: stratigraphy, structure and geochronology: Reconnaissance Pb-Pb dating of single mineral phases by the step-leaching method: results from the Caledonides of East Greenland |
title_full_unstemmed |
East Greenland Caledonides: stratigraphy, structure and geochronology: Reconnaissance Pb-Pb dating of single mineral phases by the step-leaching method: results from the Caledonides of East Greenland |
title_sort |
east greenland caledonides: stratigraphy, structure and geochronology: reconnaissance pb-pb dating of single mineral phases by the step-leaching method: results from the caledonides of east greenland |
publisher |
Geological Survey of Denmark and Greenland |
publishDate |
2004 |
url |
https://doaj.org/article/6b211c24f0724df19788fca864792224 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
East Greenland Greenland Geological Survey of Denmark and Greenland Bulletin |
genre_facet |
East Greenland Greenland Geological Survey of Denmark and Greenland Bulletin |
op_source |
Geological Survey of Denmark and Greenland Bulletin, Vol 06, Pp 67-76 (2004) |
op_relation |
http://www.geus.dk/publications/bull/nr6/nr6_p67-76.pdf https://doaj.org/toc/1604-8156 1604-8156 https://doaj.org/article/6b211c24f0724df19788fca864792224 |
_version_ |
1766398815764480000 |