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Extremely high demands for measurement accuracy in precise determination of frequency-dependent magnetic susceptibility of rocks and soils

  • František Hrouda
  • Jiří Pokorný
Article

Abstract

Frequency-dependent magnetic susceptibility, which is an important tool for environmental and palaeoclimatologic research, is usually relatively low, mostly less than 15% of the low frequency value and there is a demand for high precision of its measurement. The accuracy required for the susceptibility measurement at individual operating frequencies for precise determination of the parameter characterizing the frequency-dependent susceptibility was investigated theoretically and also experimentally through repeated measurement of artificial specimens and sediments of a loess/palaeosol sequence using the MFK1 Kappabridge. It was found that the variation in the frequency-dependence in the order of 1% is well reproducible and the measurements can be interpreted in terms of magnetic granulometry even in weakly magnetic materials.

Keywords

accuracy susceptibility frequency dependence 

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Copyright information

© Institute of Geophysics of the ASCR, v.v.i 2011

Authors and Affiliations

  1. 1.AGICO Ltd.BrnoCzech Republic
  2. 2.Institute of Petrology and Structural GeologyCharles UniversityPragueCzech Republic

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