Figures 6 and 7. Plot of uranium and iron base 10 log concentrations in data set. Ellipses represent 90 percent confidence level for membership in the three groups.
Symbols differentiate the compositional groups.
Plot of hafnium and zirconium base 10 log concentrations in data set. Ellipses represent 90 percent confidence level for membership in the three groups. Symbols differentiate the compositional groups.