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Palaeomagnetism of 935 Ma mafic dykes in southern Sweden and implications for the Sveconorwegian Loop |
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| Authors: | S A Pisarevsky G Bylund |
| Institution: | Tectonics Special Research Centre, The University of Western Australia, 35;Stirling Highway, Crawley 6009 WA, Australia. E-mail: Department of Geology, GeoBiosphere Science Centre, Lund University, Sölvegatan 12, 223 62,;Lund, Sweden |
| Abstract: | New palaeomagnetic results for the 935 Ma Göteborg-Slussen mafic dykes in southern Sweden provide a well-dated high-quality palaeomagnetic pole for Early Neoproterozoic Baltica. New U-Pb geochronological data for several palaeomagnetically studied mafic intrusions yield three additional well-dated palaeopoles and one virtual geomagnetic pole. This set of dated poles suggests minimal drift of Baltica in moderate latitudes between ～965 and 915 Ma. They also support the hypothesis of a post-900 Ma regional remagnetization event in SW Sweden and SW Norway. The positions of three distinct clusters of ～1100 to 850 Ma palaeopoles suggest a clockwise time progression of the Baltica apparent polar wander path (the Sveconorwegian Loop) during this time interval. New well-dated palaeomagnetic poles for ～970 to 900 Ma from Laurentia are required to verify the palaeogeographic reconstructions of Baltica and Laurentia. |
| Keywords: | Baltica mafic dykes palaeomagnetism Sveconorwegian Sweden |