Viscous magnetization of loess/palaeosol samples from Bulgaria

Diana Jordanova, Gergana Yancheva, Valentin Gigov
2001 Earth, Planets and Space  
The processes of acquisition of viscous remanence and its decay in zero magnetic field are studied for three sets of palaeosol and loess samples. A linear behaviour of VRM vs. log t minus is obtained for 10-10 4 min. to 30 days of acquisition experiments. Linear correlation between the obtained coefficients of viscous acquisition normalized to saturation magnetization (Sa/Js) or frequency dependent magnetic susceptibility (Sa/χfd%) and the ratio of susceptibility to saturation magnetization
more » ... s), suggests that ultra fine SP/SD grains are mainly involved in the process of viscous acquisition. Non-linear VRM vs. log t behaviour is observed during viscous decay in μ-metal shielded space, being most pronounced for the first 10 min. of the experiment. It is supposed that this phenomena is due to the presence of composite grains (core/shell structure), formed as a result of low-temperature oxidation. The latter increases towards older palaeosol units.
doi:10.1186/bf03352374 fatcat:2bcdhb7egfg5ndhr5a343upwhu