Forgot one thing I've been meaning to point out, so here's another post.
We could look at the Scablands and say this is what catastrophic flooding always does, and then look at the Grand Canyon and say "Oh it's different, so it must not have been caused by catastrophic flooding".
We could instead look at the Grand Canyon first, figure out that it was the result of catastrophic flooding, and then turn around and look at the Scablands and say "they must not be the result of catastrophic flooding".
Either would be a gross mistake. (And the differences are actually a matter of perspective anyhow.)
OR
You could look at what catastrophic flood flows look like first and then see if you can find evidence of that kind of flow (a) in the Grand Canyon and (b) in the scablands.
Curiously this is the approach used by J. Harlan Bretz when he first looked at the scablands back in 1923.
For the record this is what a broken levee looks like:
This should also be what the catastrophic floods from all your perched monster lakes should look like: because the surface of a lake is wide the depth will not drop significantly with the breaching of the dam\levee\whatever and flow will erode horizontally as well as down. Notice the rectangular shape rather than a deep v shape.
Enjoy.
Last edited by RAZD; 08/11/0812:11 AM. Reason: the the
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