Extensive study of the magnetic properties of soils and sediments by both earth scientists and biomagnetists has failed to establish the extent to which fine-grained magnetic components in the sediments' are dominated by detrital or by authigenic bacterial contributions. The question is of considerable importance to workers in a wide range of research fields. This article aims to encourage a balanced and explicit debate between biomagnetists and ‘environmental’ magnetists since, at present, they are tending to interpret their results within mutually exclusive frames of reference.
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