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The permanent magnetization of the Diabaig, Applecross and Aultbea groups of the Torridonian sandstones of north-west Scotland has been measured. That of the latter two groups is along a NW negative/SE positive axis. Field evidence shows that the majority of these rocks were magnetized soon after deposition and have retained this magnetization substantially unaltered.
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Irving et al. (1957) studied this question.
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