Reading the Rocks

Grand Canyon

One of the fun parts of geology is learning to read rocks. I don't mean reading words that people have painted or carved on them. Instead, I mean examining the rocks, looking at their minerals, structures, position, fossils, and other things to discover what they can tell us about the history of the Earth.

As with reading a book, the first thing you have to do is learn the language. You start by learning words and what they mean. Then you learn how those words fit together into sentences, and how sentences fit together to tell a story. With rocks, we start by learning some simple rules about the story rocks can tell us. Then we start looking for clues that can fill in more details, telling a more complete story.