Influence of sampling on magnetic susceptibility anisotropy of soft sediments: Comparison between gravity and piston cores

Abstract

Anisotropy of magnetic susceptibility (AMS) has been used extensively for determining mineral orientatrections. In terms of the sample coordinate, K max declinations in the three gravity cores are oriented along the core-splitting surface, whereas K max declinations in the three piston cores are perpendicular to the splitting surface. We attribute the artificial AMS to the stress created by the deformation of core liners when being split. When interpreting AMS data from sediment cores, it is necessary to investigate the influence of sampling using the sample coordinates. In this paper, we also report over-sampling and under-sampling of piston cores from a comparison of down-core magnetic susceptibility variations between piston and gravity cores. It is noteworthy that under-sampling as well as over-sampling can occur in the uppermost few meters of piston cores. © 2014 Shimono et al.; licensee Springer.