Anisotropy of magnetic susceptibility in natural olivine single crystals

Biedermann, Andrea Regina; Pettke, Thomas; Reusser, Eric; Hirt, Ann M. (2014). Anisotropy of magnetic susceptibility in natural olivine single crystals. Geochemistry, geophysics, geosystems, 15(7), pp. 3051-3065. American Geophysical Union AGU 10.1002/2014GC005386

Pettke.pdf - Published Version
Available under License Publisher holds Copyright.

Download (847kB) | Preview

Mantle flow dynamics can cause preferential alignment of olivine crystals that results in anisotropy of physical properties. To interpret anisotropy in mantle rocks, it is necessary to understand the anisotropy of olivine single crystals. We determined anisotropy of magnetic susceptibility (AMS) for natural olivine crystals. High-field AMS allows for the isolation of the anisotropy due to olivine alone. The orientations of the principal susceptibility axes are related to the olivine’s crystallographic structure as soon as it contains >3 wt % FeO. The maximum susceptibility is parallel to the c axis both at room temperature (RT) and at 77 K. The orientation of the minimum axis at RT depends on iron content; it is generally parallel to the a axis in crystals with 3–5 wt % FeO, and along b in samples with 6–10 wt % FeO. The AMS ellipsoid is prolate and the standard deviatoric susceptibility, k0, is on the order of 8*10210 m3/kg for the samples with <1wt %
FeO, and ranges from 3.1*1029 m3/kg to 5.7*1029 m3/kg for samples with 3–10 wt % FeO. At 77 K, the minimum susceptibility is along b, independent of iron content. The shape of the AMS ellipsoid is prolate for samples with <5 wt % FeO, but can be prolate or oblate for higher iron content. The degree of anisotropy increases at 77 K with p0 7757.160.5. The results from this study will allow AMS fabrics to be used as a proxy for olivine texture in ultramafic rocks with high olivine content.

Item Type:

Journal Article (Original Article)


08 Faculty of Science > Institute of Geological Sciences
08 Faculty of Science > Institute of Geological Sciences > Rock-Water Interaction

UniBE Contributor:

Biedermann, Andrea Regina, Pettke, Thomas


500 Science > 550 Earth sciences & geology




American Geophysical Union AGU




Thomas Pettke

Date Deposited:

06 May 2015 09:56

Last Modified:

15 Feb 2023 06:05

Publisher DOI:





Actions (login required)

Edit item Edit item
Provide Feedback