Grand Canyon layers: 2 billion years in one cliff
Arizona's 446 km Grand Canyon cuts 1.6 km deep to 1.8 billion year Vishnu rock carved by the Colorado over 6 million years.
446 km long 1.6 km deep cliff
The canyon runs 446 kilometers long, up to 29 kilometers wide and 1.6 kilometers deep, exposing 40 rock layers from 1840 million year Vishnu schist to 270 million year Kaibab limestone.
The Colorado River drops 600 meters over its course, moving 400000 tons of sand daily and cutting 15 centimeters per 1000 years through hard 1.8 billion year basement in the inner gorge.
Layers as pages missing chapters as gaps
Each layer is a time page 100 to 300 meters thick, with Coconino sand dunes 275 million years old, Hermit shale 280 million years and Redwall cliffs 340 million years stacked clearly.
The Great Unconformity hides 1200 million missing years where 1.8 billion year Vishnu meets 520 million year Tapeats sandstone, while the river began carving only 6 million years ago.
- Length 446 km depth 1.6 km
- Vishnu basement 1.8 billion years
- 40 layers from 1840 to 270 million years
- Colorado carving for 6 million years
- Unconformity hides 1200 million years