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A palaeomagnetic and Ar-40/Ar-39 study of mafic dykes in southern Sweden: A new Early Neoproterozoic key-pole for the Baltic Shield and implications for Sveconorwegian and Grenville loops

Elming, Sten-Ake; Pisarevsky, Sergei A.; Layer, Paul and Bylund, Göran LU (2014) In Precambrian Research 244. p.192-206
Abstract
We present the results of palaeomagnetic and Ar-40/Ar-39 studies of the Proterozoic mafic dykes in the Norrkoping and Falun areas of the southern Sweden. The primary remanence of two 939 +/- 3 Ma dykes is supported by the rigorous baked contact test. The remanence direction of two other dykes, one of which was previously U-Pb dated at 946 +/- 1 Ma is close to the reverse direction of 939 Ma dykes. Using these results together with previously published 935 +/- 5 Ma palaeomagnetic data from the Goteborg-Slussen mafic dykes and some dykes from the Falun area we calculated the mean 946-935 Ma palaeopole for Baltica (0.9 degrees S, 240.7 degrees E, A(95) = 6.7), which can be qualified as the key pole. Using this pole together with other date we... (More)
We present the results of palaeomagnetic and Ar-40/Ar-39 studies of the Proterozoic mafic dykes in the Norrkoping and Falun areas of the southern Sweden. The primary remanence of two 939 +/- 3 Ma dykes is supported by the rigorous baked contact test. The remanence direction of two other dykes, one of which was previously U-Pb dated at 946 +/- 1 Ma is close to the reverse direction of 939 Ma dykes. Using these results together with previously published 935 +/- 5 Ma palaeomagnetic data from the Goteborg-Slussen mafic dykes and some dykes from the Falun area we calculated the mean 946-935 Ma palaeopole for Baltica (0.9 degrees S, 240.7 degrees E, A(95) = 6.7), which can be qualified as the key pole. Using this pole together with other date we conclude that the Grenville and Sveconorwegian loops of Laurentian and Baltican Apparent Polar Wander Paths are temporary displaced by 100-150 m.y. We propose new palaeogeographic reconstructions of Baltica and Laurentia at ca. 940 Ma and ca. 850 Ma. We also present two new Mesoproterozoic non-key poles from 1410 Ma and 1595 Ma dykes. 2014 Elsevier B.V. All rights reserved. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Palaeomagnetism, Key pole, Neoproterozoic, Mesoproterozoic, Palaeogeography, Baltica
in
Precambrian Research
volume
244
pages
192 - 206
publisher
Elsevier
external identifiers
  • wos:000335106900014
  • scopus:84898055576
ISSN
0301-9268
DOI
10.1016/j.precamres.2013.12.007
language
English
LU publication?
yes
id
59d10cd0-ef89-423d-b199-6937c62f00ef (old id 4482558)
date added to LUP
2014-06-19 14:35:57
date last changed
2017-10-22 03:16:49
@article{59d10cd0-ef89-423d-b199-6937c62f00ef,
  abstract     = {We present the results of palaeomagnetic and Ar-40/Ar-39 studies of the Proterozoic mafic dykes in the Norrkoping and Falun areas of the southern Sweden. The primary remanence of two 939 +/- 3 Ma dykes is supported by the rigorous baked contact test. The remanence direction of two other dykes, one of which was previously U-Pb dated at 946 +/- 1 Ma is close to the reverse direction of 939 Ma dykes. Using these results together with previously published 935 +/- 5 Ma palaeomagnetic data from the Goteborg-Slussen mafic dykes and some dykes from the Falun area we calculated the mean 946-935 Ma palaeopole for Baltica (0.9 degrees S, 240.7 degrees E, A(95) = 6.7), which can be qualified as the key pole. Using this pole together with other date we conclude that the Grenville and Sveconorwegian loops of Laurentian and Baltican Apparent Polar Wander Paths are temporary displaced by 100-150 m.y. We propose new palaeogeographic reconstructions of Baltica and Laurentia at ca. 940 Ma and ca. 850 Ma. We also present two new Mesoproterozoic non-key poles from 1410 Ma and 1595 Ma dykes. 2014 Elsevier B.V. All rights reserved.},
  author       = {Elming, Sten-Ake and Pisarevsky, Sergei A. and Layer, Paul and Bylund, Göran},
  issn         = {0301-9268},
  keyword      = {Palaeomagnetism,Key pole,Neoproterozoic,Mesoproterozoic,Palaeogeography,Baltica},
  language     = {eng},
  pages        = {192--206},
  publisher    = {Elsevier},
  series       = {Precambrian Research},
  title        = {A palaeomagnetic and Ar-40/Ar-39 study of mafic dykes in southern Sweden: A new Early Neoproterozoic key-pole for the Baltic Shield and implications for Sveconorwegian and Grenville loops},
  url          = {http://dx.doi.org/10.1016/j.precamres.2013.12.007},
  volume       = {244},
  year         = {2014},
}