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RTAldan Shield
 Cambrian
 Eocambrian
 Lower Cambrian
 Neoproterozoic
 Precambrian
 Proterozoic
 Russian Federation
 upper Precambrian
SNAldan Shield area, Russian Federation. Used most often to apply to Lower Cambrian, but some have used it to refer to Neoproterozoic. Indexed with additional age terms as applicable. Added to Thesaurus in 1985.