Measurement of magnetic susceptibility anisotropy in Buntsandstein deposits from southern Germany
Item
Title (Dublin Core)
en-US
Measurement of magnetic susceptibility anisotropy in Buntsandstein deposits from southern Germany
Description (Dublin Core)
en-US
The anisotropy of magnetic low-field susceptibility in the Triassic Plattensandstein formation (Upper Buntsandstein) from northern Bavaria has a typical sedimentary fabric. The anisotropy ellipsoids are strongly oblate with minimum susceptibility axes normal to sedimentary bedding. The directions of the maximum susceptibility axes are consistent with the NNE-NE-trending general sediment transport direction that is derived from geological field observations of cross-bedding structures in the sandstones. However, the very small intensity differences between maximum and intermediate susceptibility require extremely sensitive measurement techniques. Comparative measurements were made with a spinner magnetometer, a cryogenic magnetometer and a susceptibility bridge. Directionally, the most consistent results were obtained with the spinner magnetometer after it was stabilized by means of a low-pass active filter. The directional consistency of the anisotropy principal axes can be improved further by annealing the sandstones at 750° C in air. During this treatment a strongly magnetic, low-coercivity mineral phase - probably magnetite - is formed which enhances the degree of magnetic anisotropy as well as the bulk susceptibility. Low temperature measurements indicate that, in the natural unheated state, paramagnetic minerals contribute substantially to the low-field susceptibility of the sandstones at room temperature.
ARK: https://n2t.net/ark:/88439/y006806
Permalink: https://geophysicsjournal.com/article/220
ARK: https://n2t.net/ark:/88439/y006806
Permalink: https://geophysicsjournal.com/article/220
Creator (Dublin Core)
Schultz-Krutisch, T.
Heller, F.
Subject (Dublin Core)
en-US
Rock magnetism
en-US
Low-field susceptibility
en-US
Anisotropy
en-US
Triassic red beds
en-US
Southern Germany
en-US
Solid Earth
Publisher (Dublin Core)
en-US
Journal of Geophysics
Date (Dublin Core)
1985-08-29
Type (Dublin Core)
info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
en-US
Peer-reviewed Article
Format (Dublin Core)
application/pdf
Identifier (Dublin Core)
https://journal.geophysicsjournal.com/JofG/article/view/220
Source (Dublin Core)
en-US
Journal of Geophysics; Vol 57 No 1 (1985): Journal of Geophysics; 51-58
2643-2986
2643-9271
Language (Dublin Core)
eng
Relation (Dublin Core)
https://journal.geophysicsjournal.com/JofG/article/view/220/180