[js1138]

Waterfalls are relevant, but not, I think, to the Colorado River. The problem is that the canyon and its river do not physically resemble the Niagra. If you are going to propose a scientific explanation, then you need to back it up with relevant math and expermental data. I just wonder why no one in the creationist camp is taking this obvious path, even though they want to be taken seriously as scientists.

[Doctor Stochastic]

...even though they want to be taken seriously as scientists.

Here's your problem. They do not want to be taken seriously as scientists. They (and their soulbrothers, the postmoderndeconstructionists) seem to reject entire fields (astronomy, physics, biology, geology, to name a few) of science.

[dangus]

... or simply show how all that erosion took place in the short time it took for the flood waters to recede.