北大河岩群的蚀源区存在中-新太古代的古老陆壳。

The data also imply that there are Meso- to Neoarchaean continental crusts in the source areas.

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鲁西晚太古代的侵入岩属无铕异常型，早元古代的侵入岩为负铕异常型；

This type of graphite deposits were formend in the Late Archaean to Early Proterozoic.

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地球的历史可分为四个时期——依次经历冥古代、太古代、元古代和显生宙。

The history of Earth is divided into four eons - starting with the earliest, these are the Hadean, Archean, Proterozoic, and Phanerozoic.

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We have people inventing them, but even the ones that are invented aren't very helpful, because it's awfully hard to know how they did what they did.

有人试图还原古代战争,但是得出的结果并没有太大的意义,因为我们对此实在是知之甚少

耶鲁公开课 - 古希腊历史简介课程节选