This apparently unlikely element association is unlikely to be directly related to geology, since Rb, Ba, Th, Pb and Cs tend to behave oppositely to Sc, Cr and Fe in the primary environment. It may, however, be related to glacial or post-glacial sedimentary processes, since scores of this factor show a rather strong positive correlation with both lake area and sample depth: the deeper the sample and the larger the lake, the higher the factor score.