Multidomain susceptibility and anomalously strong low field dependence of induced magnetization in pyrrhotite

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

15

Scientific paper

Large multidomain grains with high intrinsic susceptibilities ki theoretically have (total) susceptibilities k = 1/N where N is the geometric demagnetizing factor of the grain. Therefore, k should be nearly field-independent and also independent of the saturation magnetization of the magnetic material as long as ki is large. For magnetite and titanomagnetites the 1/N approximation appears to be reasonable, while for hematite ki is very small so that k ~ ki. Monoclinic pyrrhotite has susceptibilities well below the maximum possible 1/N limit, even for a millimeter-sized single crystal. Unlike magnetite the susceptibility of pyrrhotite is strongly field-dependent in the field range 8-800 A m-1 k increases with field by as much as 70% per decade, the increase being larger in fields above 80 A m-1 than below. The field dependence is also more pronounced for the single crystal and a massive ore sample than for a rock sample containing pyrrhotite grains in the size range 20-300 μm, thereby indicating a grain size dependence. The anisotropy of magnetic susceptibility (AMS) also increases with the inducing magnetic field which may complicate quantitative correlations between strain and AMS. However, the orientation of the AMS ellipsoid remains unaffected. These results are important for the determinatiob of induced magnetization for anomaly modelling. Q- factor calculations and AMS studies when pyrrhotite bearing rocks are involved.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Multidomain susceptibility and anomalously strong low field dependence of induced magnetization in pyrrhotite 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 Multidomain susceptibility and anomalously strong low field dependence of induced magnetization in pyrrhotite, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multidomain susceptibility and anomalously strong low field dependence of induced magnetization in pyrrhotite will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1718542

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.