中土世界第三纪元的那些日子早已远去，大陆地貌发生了翻天覆地的改变。

Those days, the Third Age of Middle-earth, are now long past, and the shape of all lands has been changed;

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渐新世纪第三纪始新世与中新世之间的地质纪元，大约从三千八百万年持续到二千五百万年前的一段时间。

Oligocene a geological epoch in the Tertiary, between Eocene and Miocene, lasting from about 38 to 25 million years ago.

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