Used for isotopic (radiometric or radiogenic) dating. For non-isotopic dating, see geochronology. When age is determined, the term dates is indexed with material type, isotopic dating methods and the age found. Indexed with dates or specific methods if ap
absolute age, dates
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For specific dates, see absolute age and dates.
absolute age, methods
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Not a valid GeoRef index term after 1971. Used in subfiles E, G, N, T and B.