Palaeomagnetic constraints on the ages of Tasmanian glaciations

Abstract

Field evidence indicates that Tasmania has been subjected to successive glaciations during the past few million years. However, it has been difficult to establish ages for these glaciations, and to distinguish between different phases within the main glacial stages. We describe how palaeomagnetic measurements made on glacial lake deposits have been used to test existing ideas about the relative ages of the glaciations and glacial phases. Coarse age constraints are provided by magnetic polarities. We also speculate on how additional constraints can be obtained by considering the coincidence or non-coincidence of mean palaeomagnetic directions. A more detailed account is given by Pollington (1991).