ordovician
美 英
n. 奥陶纪；奥陶系
adj. 奥陶纪的
英英释义
Noun- from 500 million to 425 million years ago; conodonts and ostracods and algae and seaweeds
例句
用作名词(n.)- This was the result from the large-scale regression in the Late Ordovician.这是奥陶纪晚期大规模海退的结果。
- Major hydrocarbon source rocks are in the Cambrian and Ordovician.寒武-奥陶系烃源岩是该区主力烃源岩;
THE END
