早奥陶世

早奧陶世
Zǎo'àotáo Shì
  1. (geology) the Early Ordovician epoch (part of the Ordovician period, spanning from 485.4 to 470 million years ago)
  2. the Early Ordovician epoch (part of the Ordovician period, spanning from 485.4 to 470 million years ago)

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