adj. 白垩的,白垩纪的
n. 白垩纪,白垩系
网络 白垩的; 白垩系; 白垩记
These animals were not as sensitive to climate changes in the Cretaceous period as they are today.
这些动物在白垩纪对气候变化不像今天这样敏感。
Scientists have linked the mass extinction at the end of the Cretaceous with a meteorite impact on Earth.
科学家将白垩纪末期的大灭绝与地球上的陨石撞击联系起来。
This change in plankton found in marine deposits is what marks the boundary between the Cretaceous and the Tertiary.
海洋沉积物中浮游生物的这种变化标志着白垩纪和第三纪的分界线。
Between the last layer of Cretaceous rock and the first layer of Cenozoic rock, there is often a thin layer of clay.
在最后一层白垩纪岩石和第一层新生代岩石之间,常常有一层薄薄的粘土。
Changes in climate before the Cretaceous period caused severe fluctuation in sea level, resulting in the extinction of the dinosaurs.
白垩纪以前的气候变化导致了海平面的剧烈波动,引发了恐龙的灭绝。