Theory of the piezomagnetic effect in titanomagnetite-bearing rocks

SummaryThe stress sensitivitiesSx andSR of susceptibility and remanence for titanomagnetite-bearing rocks are calculated in terms of magnetostriction constantsλ100 andλ111 and anisotropy constantsK1,K2 of the magnetic minerals.Sx andSR are represented by quite different algebraic expressions but happen to have comparable numerical values over the whole range of titanomagnetite compositions. Both increase strongly with titanium content. This leads to more optimistic calculations of tectonomagnetic effects than with the previously assumed stress sensitivity for pure magnetite.

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