Multimodal investigation of thermally induced changes in magnetic fabric and magnetic mineralogy

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

1

Magnetic Anisotropy, Magnetic Susceptibility, Palaeomagnetism, Rock Magnetism

Scientific paper

Low-field magnetic susceptibility and its anisotropy (AMS) were measured for a suite of sandstone and siltstone samples. AMS orientations measured on two systems (Bartington and Digico) differed before thermal treatment of the samples but became the same after thermal demagnetization in air to 600°C. Six position measurement schemes for the Bartington system do not eliminate the effects of specimen inhomogeneity and other errors, whereas 12- and 24-position measurements give good agreement with the Digico anisotropy meter and with the observed petrofabric. Thermal demagnetization from temperatures between 400 and 650°C had the effect of enhancing both the magnetic susceptibility and AMS. Although the most profound mineralogical change due to heating was the conversion of kaolinite into metakaolin, IRM, XRD, DTA and Mössbauer spectroscopic analysis demonstrate that the changes in magnetic properties were due to the transformation upon heating of trace amounts of sulphides into magnetite and/or maghemite and haematite. Both magnetic susceptibility and the degree of anisotropy decrease with higher-temperature thermal demagnetization due to the oxidation of the newly formed magnetite and/or maghemite into haematite. The magnetic foliation of the newly formed magnetite/maghemite and haematite is parallel to the bedding, possibly following the orientation of the original sulphides.

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

Multimodal investigation of thermally induced changes in magnetic fabric and magnetic mineralogy 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 Multimodal investigation of thermally induced changes in magnetic fabric and magnetic mineralogy, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multimodal investigation of thermally induced changes in magnetic fabric and magnetic mineralogy will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1292032

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