白垩纪

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。

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。

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。

Jurassic Biostratigraphic Sequence in the Middle of Northern Tibet.

辽西地区白垩纪火山岩层序探讨。

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。