Minerals such as iron and manganese gave the petrified logs at Petrified Forest National Park their color.
Photograph by Juan Carlos Muñoz, AGE Fotostock
Petrified Forest National Park boasts colorful rock formations
Photograph by © LarryKnupp, iStock, Getty Images Plus
A chemical called silica helped turned the insides of this log into rock.
Photograph by Danita Delimont, Getty Images
The petrified logs in this park are hundreds of millions of years old.
Photograph by Bjorn Holland, Getty Images
Click the full-screen arrows in the upper right to read the captions!
Thousands of logs litter a stretch of grassland at Petrified Forest National Park in northeastern Arizona. From far away, the logs might look ordinary. But they contain a surprise. The shiny, multicolored insides of the stumps are made of rock, not wood! How did the trees turn to stone? It wasn’t with the help of a magician. Instead the transformation was the result of a natural process that took place over millions of years.
During the Triassic period two hundred million years ago, the area that is now Arizona was filled with towering trees and flowing rivers. When trees fell, they often landed in the waterways. Around the same time, active volcanoes in the region spewed ash that drifted into the rivers. Ash contains a chemical called silica, which the sunken logs absorbed. Over time this caused the stumps to petrify, or turn to stone. And traces of minerals such as iron and manganese turned the logs’ rock centers different colors.
Millions of years later the rivers in the area dried up, exposing the petrified logs. To protect the ancient trees, the U.S. government turned part of the region into a national park in 1962. Today this 200,000-acre park receives around 600,000 visitors, who come to gawk at these rocks.
TAKE A HIKE
Stone stumps aren’t the only cool attraction at Petrified Forest National Park. Walking along the park’s trails, visitors can see hills made of bluish clay and the remains of a dwelling built over 600 years ago by the Puebloan peoples. Hikers might also come across tiger salamanders, prairie dogs, ornate box turtles, and other animals that inhabit the park. Talk about taking a walk on the wild side!
Text by Jamie Kiffel-Alcheh