cretaceous

词源同crayon, 石灰，粉笔。

cretaceous (adj.)

1670s, "chalky," from Latin cretaceus "chalk-like," from creta "chalk." As a geological period (with a capital C-), it was first used 1832. The extensive chalk beds of southeastern England were laid down during the Cretaceous.

1. Only in the tropics were numerous late Cretaceous groups extinguished during peaks in their evolution.

只是热带地区才有大批晚白垩纪生物类群正值其演化的极盛时期突然消亡.

2. The Cretaceous extinction was like a terrible streak of bad luck lasting millions of years.

白垩纪的生物绝灭,犹如一场持续千百万年的可怕厄运.

3. Liupanshan Cretaceous basin is a mono - basin of Liupanshan inland overlapping basin.

六盘山白垩纪盆地是六盘山内陆叠合盆地的一个单型盆地.

4. The story takes place 6500 years ago in the Cretaceous period.

故事发生在6500万年前的白垩纪晚期.

5. So the researchers resorted to some techniques out of a Cretaceous CSI.

所以科学家只能借助于《犯罪现场调查:白垩纪篇》用到的技术.