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The landscape of Australia is unique. Parts of the continent have been emergent and exposed to sub-aerial conditions for over one billion years (Figure 1); elsewhere, there has been marine sedimentation to the Holocene. Many of the landforms have their origins 300 Ma ago, when the break-up of Gondwana began. During this long period, the rocks that form the land surface have experienced a wide range of climates, including glacial, temperate and tropical, and humid to arid, with concurrent tectonic events, such as uplift, warping and continental break-up. These caused great variations in the chemical and physical environment that have resulted in intensive weathering and alteration of the exposed rocks. Because of the tectonic stability of much of the continent during the Phanerozoic, the weathered mantle, the regolith, has been preserved rather than eroded, and is present as a widespread cover, 20 to> 100 m thick over much of the continent. Generally, the regolith thus records complex interactions between weathering and erosive processes. Regolith not only includes weathered in situ materials but also transported materials of variable thickness, including complex palaeochannel systems. 1

From a geochemical exploration perspective, weathering causes the destruction of primary ore deposits and the dispersion of ore and pathfinder elements in the surrounding regolith. Conversely, it may also result in the supergene enrichment of some deposits and promote the formation of secondary orebodies. To understand the history and potential mechanisms and pathways of migration of ore and pathfinder elements in regolith, it is necessary to …