Zinc on the edge: global controls on shale-hosted zinc deposits
Channel: GeoscienceAustralia
Date: 2023-03-23

Studies of three global sediment-hosted zinc provinces (Mt Isa, Australia; Northern Cordillera, Canada/USA; Irish Midlands, Ireland) indicate that deposits in all three provinces are associated with gradients in many geological parameters. These include lead isotopes, the depth of the lithosphere-asthenosphere boundary, upward-continued gravity and magnetotellurics data. These gradients are interpreted to mark major cratonic boundaries, or edges, that control the distribution of these deposits in space and in time. Studies of the Mt Isa Province indicate that regional alteration has caused extensive loss of zinc, copper and cobalt, potentially providing more than sufficient metal for the known deposits. Moreover, in some cases, metal loss corresponds to changes in rock properties, possibly enabling regional mapping of zones of metal loss using geophysical data.