K-T boundary是什么意思

双语例句

(1)The reason why an asteroid was looked at as the cause of the Iridium spike at the K-T boundary, is because asteroids have an enormous amount of Iridium in them.

一颗小行星被看做是引起KT界限层铱猛增的原因，是因为小行星中有相当多的铱。

(2)The K-T boundary marks the end of the age of dinosaurs, and the beginning of the age of mammals.

KT界限层标志着恐龙时代的终点和哺乳动物时代的开端。

(3)The layer that separates the periods is called the K-T boundary.

这区分两个纪元的土层被称作KT界限层。

(4)It needed to be the right size to be linked to the K-T boundary evidence.

要与KT界限层的证据连接起来，它的大小必须合适。

(5)But does the K-T boundary really signify the absolute end of all dinosaurs?

不过KT界限层真的标志着所有恐龙的彻底消亡吗？

释义

short for CRETACEOUS-TERTIARY BOUNDARY.

CRETACEOUS-TERTIARY BOUNDARY的简称。

词源

"late 20th cent.: K／T, from the symbols for Cretaceous and Tertiary."