Geologic column---dating??From the evolution textbook...
Why does it look like it does(grand canyon)?
So I guess no low angle subduction causing isostatic uplift of the Colorado Plateau?
but that doesn't mean below ground layering on plates---
and canyon cracks expansion/layering didn't happen either!
Few more minutes on the 'BIG' question/challenge---TEST!
Hope I don't disappoint you!