康定杂岩以往被认为是扬子地块太古宇的基底，但近年来的同位素年龄测定结果表明其并不是形成于太古宙。

The complex was traditionally considered as the Archean basement of the Yangtze Block, but recent isotopic dating results indicate that it was not formed in Archean.

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因为它是稀有天然放射性同位素钾衰变而产生的，所以可以用来测定十万年以上的岩石年龄和采样。

Because a radioactive form of argon is produced by decay of a naturally occurring radioactive potassium isotope, it can be used to date rocks and samples more than 100,000 years old.

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