Remagnetisation of a rock analogue during experimental triaxial deformation

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

13

Scientific paper

Synthetic specimens containing pseudo-single-domain magnetite were given a univectorial, anhysteretic remanent magnetisation. They were deformed in a ductile manner at room temperature under a confining pressure of 150 MPa (1.5 kbar). The strain rate was 10-5 s-1 and the maximum strain achieved was 23% shortening. A weak (0.035 mT) magnetic field was present in the pressure vessel during deformation. Hydrostatic compaction alone produced pressure demagnetisation of low-coercivity components of remanence but did not change remanence directions. Macroscopic differential stress was needed to deform the specimens, and this also permitted syndeformational remagnetisation for values of more than 20 MPa (200 bars). This added new components of piezo-remanent magnetisation (PRM) approximately parallel to the direction of the magnetic field in the pressure vessel. They were acquired in all coercivity intervals but the largest components were added below 35 mT. The final remanence orientation and its spatial distribution of vector components were dictated by the relative orientations of the remagnetising field and the initial remanence. PRM contributions almost completely masked the changes related to strain-induced grain rotation at these low strains. The directions of the externally imposed stress-strain axes may not significantly influence the direction of new remanence components. PRM acquisition occurs when differential stress exceeds a threshold value that probably depends on the previous stress-history of the magnetite grains. In part, this may explain the origin of syntectonic remagnetisation in some naturally deformed rocks where the remanence is not reset by recrystallisation, or thermal or chemical processes.

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

Remagnetisation of a rock analogue during experimental triaxial deformation 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 Remagnetisation of a rock analogue during experimental triaxial deformation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Remagnetisation of a rock analogue during experimental triaxial deformation will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1680776

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