I came across this in my nightly "relaxing science article" reading. The blog post has some good geology and goes into detail about the depositional environments as well as some of the correlations of formations seen on Lodore with others throughout the West.
Here's Part I:
Rafting the Geology of the Canyon of Lodore, Colorado
Nothing in the world is more yielding and gentle than water. Yet it has no equal for conquering the resistant and tough. The flexible can overcome the unbending; the soft can overcome the hard. - Lao Tse