Biogeochemical prospecting using lead isotopes

One aspect of CSIRO's continuing investigations into the use of lead isotopes in mineral exploration, particularly for concealed mineralization, involves the analysis of vegetation. Because lead isotopic ratios are not changed by weathering or biological processes, the technique offers the following advantages over conventional biogeochemical prospecting: (1) Species selection is not as critical. (2) The plant organ (e. g. , twigs versus leaves) is not critical. (3) There does not have to be quantitative uptake of Pb by the vegetation. The major disadvantage of the lead isotope technique is cost, and thus detailed regional vegetation surveys are not feasible at the present state of technology.