The side canyons in the photo of the confluence of the Green River and the Colorado were obviously not cut by the meandering river.
Nor do the canyon walls down below.
And yet, they are cut down to the same level as the river.
The river flows down into a wide canyon that doesn't conform to any of the rivers flow path.
It appears that all the canyon rim features are common in their appearance and are thus not due to the river since many of them are great distances from the river.
I see no evidence here that the river produced all these terrain features. And, if it didn't then what is the cause of correspondence between the side canyons and the main river channel in that the side canyons are oriented with it, and yet not formed by it, and yet at the same time they have been cut to the same depth?
It is the same at the grand canyon. If you plot the river's beginning up at the top of the canyon you'll notice that it can't have been a meandering river at that time. It appears that only after some extensive collapse of the rims into a deepening canyon did the river begin to meander at some point.
Joman.
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