Erratum to: Natural Resources Research, Vol. 16, No. 2, June 2007 DOI: 10.1007/s11053-007-9036-7

The incorrect version of Figure 4 was inadvertently placed in the article. The correct version follows on the next page.

Fig. 4
figure 1

Multi-class predictive patterns of U/Th ratio (A), total magnetic field (B), U/K ratio (C), and geology (D)