The Cretaceous-Tertiary (K-T) boundary is a thin clay layer somewhere on the bottom of this outcrop. Don't ask me why the acronym for "Cretaceous" is "K". I mean, like, it's so obvious if you speak Italian or German.

 The K-T boundary is approximately 65 million years old.

 While dinosaurs ruled the Earth during the Cretaceous, no dinosaur fossils have ever been found in Tertiary sedimentary rocks.

 A large meteorite hit the Earth at the end of the Cretaceous, which may have caused the mass extinction.