As in theOligocene before it, grasslands continued to expand and forests to dwindle in extent.
在先前的渐新世,草地的面积增大,森林的面积减少。
2
The high relative abundance of the fossil planktonic algae indicates the high primary surface productivity of the palaeo-lake within theOligocene.
文昌组浮游藻类相对丰度高,表明始新世珠江口古湖的表层水初始生产力高。
3
It peaked in theOligocene Epoch around 34 million years ago in Eurasia, and again in the Miocene Epoch about 10 million years ago in Eurasia and Africa.