The nature and distribution of regolith carbonate accumulations in southeastern Australia and their potential as a sampling medium in geochemical exploration

Regolith carbonate accumulations are widespread in the southern part of the Australian continent and have been successfully used in the Yilgarn and Ga wler cratons as a sample medium in Au exploration. The association of Au wi th carbonate in regolith profiles has now been established for southeastern Australia, particularly in the semi-arid regions of western New South Wale s. This association can be used at both regional and local anomaly scales. Sampling of regolith carbonate accumulations has potential to be an importa nt exploration technique in the region for both Au-only and Au-bearing poly metallic mineralisation. Demonstrated variability in carbonate morphology, mineralogy and chemistry, as well as the landscape setting and aspects of c arbonate genesis and dispersion pathways, need to be considered when establ ishing sampling strategies and regional and local thresholds. It is recomme nded that a thorough orientation survey be carried out in a region before a pplication of the technique. (C) 1999 Elsevier Science B.V. All rights rese rved.