LATE CARBONIFEROUS LATE PERMIAN PALEOMAGNETIC OVERPRINTING OF CARBONIFEROUS GRANITOIDS IN SOUTHERN BOHEMIAN MASSIF (AUSTRIA)

Paleomagnetic investigations on Early-Middle Carboniferous granitoids of the Austrian part of the South Bohemian Pluton (48.5 degrees N, 14. 2 degrees E) yielded two groups of characteristic remanent magnetizati on (ChRM) directions, one being characterized by SSW-declinations and positive inclinations and labelled A1 (D = 200 degrees, I = 14 degrees , k = 67, N = 9; virtual geomagnetic pole (VGP) 31 degrees N, 170 degr ees E), the other group having the same declinations but with negative inclinations (D = 201 degrees, I = -21 degrees, k = 88, N = 18; VGP 4 8 degrees N, 162 degrees E). Both magnetizations are considered as mag netic overprints owing to distinct recrystallization processes that oc curred in different hydrothermal and tectonic conditions in Late Carbo niferous and Late Permian times. In some cases the original magnetizat ions may remain after the remagnetization processes, but as a whole th is study confirms that the paleomagnetic history of a magmatic crystal line basement (in this case of Late Carboniferous to Late Permian age) maybe differ significantly from its intrusion history (in this case E arly to Middle or Late Carboniferous).