| |
 |
UNIVERSITY OF BUCHAREST
FACULTY OF PHYSICS Guest
2024-11-24 22:10 |
 |
|
|
|
Conference: Bucharest University Faculty of Physics 2004 Meeting
Section: Atmosphere and Earth Science; Environment Protection
Title:
Magnetic mineralogy of Upper Cretaceous magmatic rocks from the Apuseni Mountains
Authors:
Aneta Nedelcu, Cristian Panaiotu
Affiliation:
University of Bucharest, Faculty of Physics
E-mail
panaiotu@geo.edu.ro
Keywords:
magnetic mineralogy, paleomagnetism, Apuseni Mountains
Abstract:
Paleomagnetic data obtained from Upper Cretaceous magmatic rocks of the Apuseni Mountains play a key role in understanding the last 80 Ma tectonic history of the Transylvanian Basin. To identified what type of ferromagnetic crystals are present in these rocks, we did several rock magnetic studies: acquisition of isothermal remanent magnetization (IRM), back field and alternating field (AF) demagnetization of the saturation IRM, acquisition and AF demagnetization of anhysteretic remanent magnetization (ARM). IRM acquisition and back field demagnetization was obtained using a Pulse Magnetizer with a maximum field of 2T. ARM was obtained in a DC magnetic field of 0.05 mT and a maximum AF field of 200 mT. All measurements were done in the Paleomagnetic Laboratory of University of Bucharest. Results show that magnetic mineralogy is dominated by titanomagnetite serie, but in some sample also high coercivities crystals are present (hematite and probably maghemite or highly oxidized magnetite). These data are compared with AF and thermal demagnetization of the natural remanent magnetization of studied rocks. This analysis will allow us to asses the best demagnetization method to identify the primary remanent magnetization which is used for tectonic reconstruction.
|
|
|
|