Age determination on rock samples from Svalbard ...
A linear, N-S-trending belt of elliptical, positive magnetic anomalies occurs in central Nordaustlandet, northeast Svalbard. They extend from the Caledonian and older complexes in the vicinity of Duvefjorden, southwards beneath the western margin of Austfonna and the offshore areas covered by Carbon...
Main Authors: | , , , |
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Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
PANGAEA
2011
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Subjects: | |
Online Access: | https://dx.doi.org/10.1594/pangaea.763739 https://doi.pangaea.de/10.1594/PANGAEA.763739 |
Summary: | A linear, N-S-trending belt of elliptical, positive magnetic anomalies occurs in central Nordaustlandet, northeast Svalbard. They extend from the Caledonian and older complexes in the vicinity of Duvefjorden, southwards beneath the western margin of Austfonna and the offshore areas covered by Carboniferous and younger strata, to the vicinity of Edge¯ya. One of the strongest anomalies occurs in inner Duvefjorden where it coincides with a highly magnetic quartz monzonite-granite pluton at Djupkilsodden. U-Pb and Pb-Pb zircon dating of this post-tectonic pluton defines an age of c. 415 Ma, this being based on the Pb-Pb analyses of three specimens (Pb-Pb ages of 414±10 Ma, 411±10 Ma and 408±10 Ma) and a U-Pb discordia with an upper intercept at 417+18/-7 Ma. Neighbouring felsic plutons in central Nordaustlandet, including the Rijpfjorden and Winsnesbreen granites, lack magnetic signatures in their exposed parts, but have a similar Caledonian age. The central Nordaustlandet magnetic anomalies appear to be part of ... : Supplement to: Gee, David G; Johansson, Åke; Larionov, Alexander N; Tebenkov, Alexander M (1999): A Caledonian Granitoid Pluton at Djupkilsodden, Central Nordaustlandet, Svalbard: Age, Magnetic Signature and Teetonic Significance. Polarforschung, 66(1/2), 19-32 ... |
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