CAILLOU NOIR

MAGNETIC SUSCEPTIBILITY OF METEORITES

This is just a first estimation of meteorite types according to their magnetic susceptibility, measured thanks to SM30 equipment.

Information provided by Pierre Rochette and Jérôme Gattacceca. Thanks!

In the diagram beside, LogX values of some terrestrial rocks are also indicated in order to make the comparison with meteorites:

(sed: sedimentary rocks, gra: granitoids, vol: volcanics, met: metamorphic rocks).

The three types of OCs have also been spotted: LL, L & H.

Values for meteorites in this diagram, come from measurements performed on witnessed falls. Average values for finds can be expected as lower and also with a wider variation, specially fo meteorites that contain iron, such as OCs.

When knowing the magnetic suceptibility of a meteorite measured with the SM30 system, and when having already an idea of the type, you can find out most of the times, thanks to the diagrams shown above, the exact type of meteorite you have.

For instance, if having an O.C. wich magnetic suceptibility is 5,28, you most certainly have an H chondrite.
Should the LogX value be 4.9, it is then more difficult to make the difference between a highly weathered H chondrite and a fresh L chondrite.

Of course some scientific publications have already been provided and here are some of them that are availabel on the Net:
- METEORITE IDENTIFICATION AND CLASSIFICATION USING MAGNETIC SUSCPETIBILITY:
http://www.lpl.arizona.edu/~bcohen/publications/LPSC06_SIPI.pdf

- MAGNETIC SUSCEPTIBILITY OF STONY METEORITES FROM THE NATIONAL METEORITES COLLECTION OF CANADA: http://www.lpi.usra.edu/meetings/lpsc2003/pdf/1939.pdf
-
Density, magnetic susceptibility, and the characterization of ordinary chondrite falls and showers:
http://www.ingentaconnect.com/content/arizona/maps/2006/00000041/00000003/art00001;jsessionid=sxfx5i3gfvpu.alice
- Magnetic Classification of Stony Meteorites ( Authors: Rochette, Pierre; Sagnotti, Leonardo; Bourot-Denise, Michèle; Consolmagno, Guy; Folco, Luigi; Gattacceca, Jérôme; Osete, Maria Luisa; Pesonen, Lauri ):
http://www.ingentaconnect.com/content/arizona/maps/2003/00000038/00000002/art00006;jsessionid=4kz1wrlk02d.alice
- In situ identification, pairing and classification of meteorites from Antarctica through magnetic susceptibility measurements
(
Authors: Folco, Luigi; Rochette, Pierre; Gattacceca, Jérôme; Perchiazzi, Natale)
http://www.ingentaconnect.com/content/arizona/maps/2006/00000041/00000003/art00002;jsessionid=dk3kodj64k47.alice

 

© Caillou Noir / Michel Franco 2005 / 2006