Cave-ins and floods may have buried the Cretaceous creatures of the fossil Jehol Biota rather than volcanic eruptions, a new study claims.

What Was Happening on Earth at This Time The Precambrian is the earliest of the geologic ages, which are marked by different layers of sedimentary rock. Laid down over millions of years ...

The next layer is the mantle. Many people think of this as lava, but it's actually rock. The rock is so hot, however, that it flows under pressure, like road tar. This creates very slow-moving ...

"Scroll Down through History" displays the layers of rock exposed within the Grand Canyon and shows when in earth's history they formed. The region where the Grand Canyon now lies begins to shift ...