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Antiphase domains and reverse thermoremanent magnetism in ilmenite-hematite minerals

C.A. Lawson·Gordon L. Nord·Eric Dowty·R.B. Hargraves
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Abstract

Examination of synthetic ilmenite-hematite samples by transmission electron microscopy has for the first time revealed the presence of well-defined antiphase domains and antiphase domain boundaries in this mineral system. Samples quenched from 1300°C have a high density of domain boundaries, whereas samples quenched from 900°C have a much lower density. Only the high-temperature samples acquire reverse thermoremanent magnetism when cooled in an applied magnetic field. The presence of a high density of domain boundaries seems to be a necessary condition for the acquisition of reverse thermoremanent magnetism.

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C.A. Lawson, Gordon L. Nord, Eric Dowty, R.B. Hargraves. 1981. Antiphase domains and reverse thermoremanent magnetism in ilmenite-hematite minerals. https://doi.org/10.1126/science.213.4514.1372

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