To complete this activity, download and print the Student Question Sheet.

Researchers in Grand Staircase-Escalante National Monument have been studying iron concretions to determine exactly how they were formed. When the Voyager mission on Mars discovered similar concretions, NASA scientists turned to research from Earth to help solve a mystery on Mars.

This activity will look at the chemistry of iron concretions, their formation over geologic time, and how scientists applied this research to recent discoveries on Mars.

In Grand Staircase-Escalante National Monument and elsewhere on planet Earth there are red rock formations. The red color is often an indication of iron. In some formations, like Navajo sandstone in the Monument and Zion National Park, much of the red color is gone. The reason for this variation in rock color is due in part to the chemistry of iron.