The diagram shows that the Grand Canyon consists of many different layers of rocks. The rocks on the bottom are the oldest and they get younger as you reach the top. This follows the law of superposition. From younger to older they are:

• Kaibab-Toroweap limestone
• Coconino sandstone
• Hermit shale
• Supai sandstone
• Redwall limestone
• Muav limestone
• Bright Angel shale
• Tapeats sandstone
• Vishnu schist