Studia Geophysica et Geodaetica

, Volume 47, Issue 4, pp 847–861 | Cite as

Indices for Numerical Characterization of the Alteration Processes of Magnetic Minerals Taking Place During Investigation of Temperature Variation of Magnetic Susceptibility

  • František Hrouda


The alteration of magnetic minerals taking place during the investigation of the temperature variation of bulk magnetic susceptibility is obvious from different courses of heating and cooling susceptibility vs. temperature curves. A set of indices is introduced to characterize these changes numerically. The A40 alteration index characterizes the change in susceptibility after executing the whole cycle of heating and cooling. The maximum difference between the heating and cooling curves is characterized by the Amax alteration index. The mean or average difference between the heating and cooling curves is characterized by the Am alteration index. The situation whether the heating and cooling curves cross, is characterized by the Acr alteration index. The technique of progressive repeated heating is proposed, together with the above indices, to locate the temperature intervals with weak and strong magnetic mineral changes induced by heating.

temperature variation of susceptibility repeated heating magnetic fabric enhancement peleointensity studies 


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© StudiaGeo s.r.o. 2003

Authors and Affiliations

  • František Hrouda
    • 1
    • 2
  1. 1.AGICO Inc.Ječná 29aBrnoCzech Republic
  2. 2.Institute of Petrology and Structural GeologyCharles UniversityPragueCzech Republic

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