H. De Wall et Ro. Greiling, Remagnetisation and magnetic refraction in Proterozoic dykes from central Scandinavia during Caledonian deformation, PHYS CH P A, 25(5), 2000, pp. 519-524
Citations number
17
Categorie Soggetti
Earth Sciences
Journal title
PHYSICS AND CHEMISTRY OF THE EARTH PART A-SOLID EARTH AND GEODESY
Mafic dykes, related to the Central Scandinavian Dolerite Group, changed th
eir geometry during the Caledonian orogeny from flat-lying bodies in the Au
tochthon to steeply inclined in the thrusted and stacked Lower Allochthon u
nits. During tectonic transport remagnetisation occured and the post-Jotnia
n paleomagnetic signature was completely obliterated. In the Bangonaive win
dow this remagnetisation occurred at a deeper crustal level probably during
metamorphism and deformation under amphibolite-facies conditions, while in
the Borgefjell window it was caused by alteration in a more shallow crusta
l level. In both tectonic windows the remanence direction is influenced by
the structure, and in the strongly anisotropic samples of the Bangonaive wi
ndow a distinct refraction of the remanence direction (up to 15 degrees) to
wards the magnetic lineation is observed. (C) 2000 Elsevier Science Ltd. Al
l rights reserved.