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Earth and Space Sciences · 术语表

什么是 Era and geological period?

又称: era · geological period

Definition 22.9 Primary & Middle School Earth and Space Sciences · 第 22 章 — The Ages of the Earth

An era is a long span of the Earth’s history, set by the general kind of life that existed at that time: the Paleozoic, the Mesozoic and the Cenozoic. Each era is divided into shorter spans, the geological periods, such as the Jurassic or the Cretaceous.

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