Physics
Scientific paper
Apr 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006geoji.165...17r&link_type=abstract
Geophysical Journal International, Volume 165, Issue 1, pp. 17-31.
Physics
8
Scientific paper
17 single crystals were identified by electron backscatter diffraction (EBSD) and isolated from coarse massive haemo-ilmenite ore from South Rogaland, Norway. These were studied using the EBSD results, natural remanent magnetization (NRM), and anisotropy of magnetic susceptibility (AMS), to gain a better understanding of angular relationships between crystallographic axes and magnetic properties of haemo-ilmenite in relation to lamellar magnetism. Electron microprobe analyses gave the following average end-member compositions for ilmenite host: 21.1 per cent MgTiO3, 73.7 FeTiO3, 0.5 MnTiO3, 4.3 Fe2O3, 0.2 Cr2O3 and 0.3 V2O3; and for the coarsest (~3 μm) haematite exsolution lamellae: 3.5 MgTiO3, 22.4 FeTiO3, 71.4 Fe2O3, 1.6 Cr2O3, 1.0 V2O3 and 0.1 Al2O3, making this sample the most Mg- and Cr-rich haemo-ilmenite studied in the province, but with similar element fractionations between the coexisting phases. TEM work on similar material suggests the presence of much thinner exsolution down to 1-2 nm.
The EBSD, NRM and AMS results from 12 out of 17 crystals indicate a good agreement between the orientation of crystallographic axes, NRM direction and principal axes of the magnetic susceptibility ellipsoid, with the NRM located in the (0001) basal plane [NRM ∧ (0001) < 6.5°] and the crystallographic c axis quasi-parallel to the minimum axis of the susceptibility ellipsoid [c∧ k3 < 13.5°]. In addition, in 10 of these 12 crystals, the remanent magnetization vector is parallel or nearly parallel to the positive direction of a crystallographic a axis [NRM ∧a < 20°], hence parallel to a principal magnetic moment direction in haematite as determined by Besser et al., and not parallel to the spin-canted direction of end-member haematite. This is consistent with a basic property of lamellar magnetism, where the magnetic moment is parallel to the principal moments (sublattice magnetization directions) in haematite. Relationships in three additional crystals with NRM ∧a= 22°-33°, only two with good agreement, can be interpreted as consistent with having a magnetic vector quasi-parallel to the spin-canted direction of haematite.
Brown Laurel
Heidelbach Florian
Hirt Ann M.
McEnroe Suzanne A.
Robinson Patricia
No associations
LandOfFree
Crystallographic-magnetic correlations in single-crystal haemo-ilmenite: new evidence for lamellar magnetism does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Crystallographic-magnetic correlations in single-crystal haemo-ilmenite: new evidence for lamellar magnetism, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Crystallographic-magnetic correlations in single-crystal haemo-ilmenite: new evidence for lamellar magnetism will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1166072