Talk:Barberton Greenstone Belt

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South Africa

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What is Ga

Hi, Reading the entry, there is no explanation of what " oldest exposed rocks on Earth (greater than 3.6 Ga)" means. I've "sort of" understood it, I'm guessing 3.6 billion years; but I do not know, so cannt add a link. Could someone add a link to "Ga" to the explanation (I assume there is a Wiki page explaining it somewhere). Thanks. ScientistOld (talk) 08:27, 22 October 2024 (UTC)[reply]

Further: I've found this: https://wiki.riteme.site/wiki/Year

In astronomy the abbreviations kyr, Myr and Gyr are in common use for kiloyears, megayears and gigayears.[27][28]

... but this seems to be a different set of abbreviations for the same thing. — Preceding unsigned comment added by ScientistOld (talk • contribs) 08:32, 22 October 2024 (UTC)[reply]