Авторы: Fabian K. and Hubert A.

1999 г.

Geophys.J.Int.

Models of uniaxial hard magnetic particles show that irregularly shaped grains possess a considerable equilibrium remanence due to domain imbalance. This remanence decreases approximately as L{1 with grain size L and is very stable with respect to alternating ¢eld and thermal demagnetization. It is therefore likely to be a major source of pseudo-single-domain remanence in rocks. Using the methods of domain theory, the range of possible remanences in irregularly shaped uniaxial particles with less than ¢ve domains is investigated. Even for slightly asymmetric particle geometries the remanence decreases monotonically with grain size. Most two-domain remanences lie above 0.3 Ms. The behaviour of the domain imbalance moments seems to be largely independent of details of the shape asymmetry. Since domain imbalance is a global equilibrium remanence, local remanences due to wall pinning e¡ects can be superimposed without destroying it. This can explain the fact that the remanence of pseudo-singledomain particles appears to be a mixture of independent single- and multidomain-like components.

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