Impact of fire on the Weipa Bauxite, northern Australia

Abstract

More than half of western Cape York Peninsula experiences fire every dry season, and the effects of this on the bauxite are twofold: gibbsite is dehydrated to boehmite or alumina and Fe-oxyhydroxides are converted to maghemite. Effects are most significant on the earthen materials of termite nests, particularly those coating the trunks of the common Eucalyptus tetrodonta (Darwin stringybark), and where dead trunks, branches and roots have burnt. Fire-induced dehydration of ooliths in termite nests is suggested as the source of the high-boehmite redsoil in the Weipa Bauxite deposit.