They have been slowly recycled over millions of years.This is called the rock cycle.Sedimentary rocks form ... Look at the diagram to get a better understanding of all the different processes ...

The Rock Cycle is Earth's great recycling process where igneous, metamorphic, and sedimentary rocks can all be derived from and form one another. Analogous to recycling a Coke can, where an old ...

Liam Squires, a fifth grader in Virginia, found a mistake in a book’s diagram ... the sedimentary rock and igneous rock were swapped into the wrong spots in the rock cycle.

A 'Level 5' tome covering Earth Science, the book was approved by the school district back in 2015 - but a mistake involving a diagram depicting the geological rock cycle managed to creep through.