[count-your-change]

And that would have required water and a active drainage basin over a very long period of time plus a period of time for the present formation to rise above the surrounding area.

Any thoughts on this?

[dirtboy]

And that would have required water and a active drainage basin over a very long period of time plus a period of time for the present formation to rise above the surrounding area.

Given the uplift has been going on for about 1.5 to 2 million years, I'd say there has been plenty of time for such. Heck, the Rockies were buried up to their chins in debris and were exhumed over the last ten million years as the region rose about a mile in elevation.