cretaceous

白垩纪的地质

These fossils come from cretaceous rock layers in the desert.

这些化石来自沙漠中的白垩纪岩层。

白垩质的、含白垩的地质

The cliffs are made of soft cretaceous material that erodes easily.

这些峭壁由松软的白垩质岩石构成，很容易被侵蚀。

白垩纪常大写并加 the

Flowering plants first spread widely during the Cretaceous.

开花植物在白垩纪首次大量繁衍扩散。