Congratulations, you've suckered me in.
Sun, 30 Nov 1997 21:08:22 -0600 Glenn Morton wrote:
> Remember that volcanic ash is very soft and of ONE lithology.
More than one lithology was cut by the 1982 mudflow at Mt. St. Helens.
Ancient solid rock was also cut.
> The Grand
> Canyon has many different lithologies. The situation at Spirit Lake is quite
> different from the Grand Canyon.
Correct, in scale only. I understand several hundred cubic miles of
water would be impounded behind the Kiabab Uplift if it were not cut by
Grand Canyon. This natural dam would have trapped water as the Flood
receded. A breach in the dam would have eroded out rapidly and allowed
the impounded lake to discharge within perhaps a few weeks, cutting
Grand Canyon catastrophically.
Question, Glenn. If the Canyon eroded slowly (over millions of years)
as it is doing today, where is the delta? The delta at the mouth of the
Colorado River looks pretty puny on the aerial photos I've seen. You
have to not only account for the volume removed from the Canyon, but
also the upland plateau material removed from between the mesas. Where
is it?
I still have a little crow left, if you want a slice to be chewing on.
I think between the two of us, we can pin him this time, Art.
Bill Payne