Neogene period

It is one of the geological time divisions, and is the second period when dividing the Cenozoic Era, and is a general term for the Miocene and Pliocene periods. It refers to the period from approximately 23.03 million years ago to 2.58 million years ago. The strata formed during the Neogene period are called the Neogene System. The climate was warm until the middle of the Miocene, when there was a significant sea level rise, and then it gradually cooled. This was a time of significant uplift of major mountain ranges such as the Himalayas and the Alps. Biogeographical regions were formed that are almost the same as today. In the animal kingdom, there is an increase in the number of organisms that are common to the present compared to the Paleogene, but in the plant kingdom, there is no significant difference from the Paleogene.

[Toshiyuki Yamaguchi August 19, 2015]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

地質時代の時代区分の一つで新生代を時代区分したときの2番目の紀であり、中新世、鮮新世をあわせた時代の総称。およそ2303万年前から258万年前までの時代をいう。新第三紀に形成された地層を新第三系という。気候は、中新世中期までは温暖で、顕著な海進期にあたり、その後徐々に寒冷化した。ヒマラヤ―アルプスなどの主要な大山脈の著しい隆起の時代にあたる。現在とほぼ同じ生物地理区ができた。動物界では古第三紀に比べて現在と共通する生物の種の増加が認められるが、植物界では古第三紀との違いは著しくない。

［山口寿之　2015年8月19日］

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