Scablands and a catastrophic flood

[otseng]

https://hugefloods.com/Scablands.html

"It was the biggest flood in the world for which there is geological evidence," writes Norman Maclean in A River Runs Through It, referring to the catastrophic deluge that tore through the Pacific Northwest every time Glacial Lake Missoula's ice dam gave way. "t was so vast a geological event that the mind of man could only conceive of it but could not prove it until photographs could be taken from Earth satellites." Proof now in hand, geologists today point to numerous features in the landscape that reveal the extreme scale and violence involved in these truly colossal floods.

Mystery of the Megaflood

J. Harlen Bretz, who theorized that the Washington Scablands was formed by a catastrophic flood, was of course first met with intense opposition.

Bretz conducted meticulous research and published many papers during the 1920s describing the Channeled Scablands. His theories of how they were formed required short but immense water flows, for which Bretz had no explanation (the source of the water was never the focus of his research). Bretz's theories met with vehement opposition from geologists of the day, who tried to explain the features with uniformitarianism theories.

http://en.wikipedia.org/wiki/Scablands

However, it is now commonly accepted among scientists that the Scablands was formed by a catastrophic flood (which I think this by itself is very interesting). And not only that, it was formed relatively recently too - around 15000 years ago (which also is very interesting).

Questions which I'd like to discuss:

Where did the water come from?
If a catastrophic flood created the Scablands in a short period of time, couldn't other geological features elsewhere be also created in a short amount of time?

[juliod]

One question is how could it've formed to this depth over time without the hydrostatic pressure of water to collapse it before it got to be so large?

I think you are thinking of this as a process of building-up rather than thawing. I'm thinking that the putative icedam was not built, but rather left-over as the continental-sized icesheets melted. An inland sea could form, under the right conditions, and would drain all at once when the weakest part of its melting rim gave way.


DanZ

[otseng]

Note that the actual volume of the lake is irrelevant to the pressure, only the height of the dam matters.

This is one of the problems I see with the ice dam hypothesis. Someone is going to have to prove to me that ice alone can hold back water that is 2000 feet high. Even if it was created by a continent sized glacier, it would still have this problem.

The largest dam we've created with steel and concrete is 630 feet tall, so how can ice create a dam over 3 times in height and hold back that much pressure?

[otseng]

Let me go a little bit into what the flood did...

More than one hundred years ago, geologists began to ponder the landforms in eastern Washington State. They noticed that the land surface is essentially flat and underlain by thick and extensive basalt flows, with only a thin soil cover. They called this area a scabland. Geologists also observed a braided pattern of deep channels appearing as severely scrubbed bare rock surfaces eroded through the soil cover into the basalt bedrock. Most of these channels now dry and are called "coulees." This 16,000-square-mile area of eastern Washington became known as the "Channeled Scabland."

http://www.icr.org/article/2977/

The volcanic rock base (basalt) of the Scablands is seen on the map below:


https://fermi.jhuapl.edu/states/maps_bw/wa_bw.gif

The flood eroded to the basalt layer (Columbia River Basalt Group). The basalt layer is estimated between 17 million to 6 million years old.
http://vulcan.wr.usgs.gov/Volcanoes/Col ... ateau.html

Map of flooded area:

http://vulcan.wr.usgs.gov/Volcanoes/Col ... ateau.html

The flood eroded hundreds of feet of rock. Dry Falls has a 400 foot rock face which was eroded by the flood. (Niagara Falls has a drop of 165 feet)
http://en.wikipedia.org/wiki/Dry_Falls

A picture of Dry Falls:



Grand Coulee Canyon, at 50 miles in length, and 1 to 5 miles across, is the largest of the channels gouged by a deluge.
http://www.gonorthwest.com/Washington/n ... _Falls.htm

A picture of the Grand Coulee Canyon:



In total, the flood carved out 50 cubic miles of earth.
http://www.nps.gov/iceagefloods/d.htm

[jwu]

This is one of the problems I see with the ice dam hypothesis. Someone is going to have to prove to me that ice alone can hold back water that is 2000 feet high. Even if it was created by a continent sized glacier, it would still have this problem.

What exactly is supposed to happen? Ice itself is very stable, and a many dozen miles thick wall of it should easily be able to withstand a pressure of 60kg per square centimeter at the bottom. After all, its own weight already exerts a similar pressure onto it.

The largest dam we've created with steel and concrete is 630 feet tall, so how can ice create a dam over 3 times in height and hold back that much pressure?

That's a wall only a few meters thick though which holds all that water, compared to miles of thickness of an ice wall. Moreover, just because humans haven't built any damns beyond that size doesn't mean that we couldn't. Perhaps we're just lacking nice places or it would be too expensive to be practical.

Note that the highest man man structures are surpassed several times by ice thickness as well...

[otseng]

We have 50 cubic miles of earth eroded within 3 days. It eroded hundreds of feet of rock all the way down to the Columbia River Basalt Group.

So, here is the problem. How could water (even if it was moving at 45 miles per hour) erode solid rock hundreds of feet thick within 3 days? How do we know it was all solid rock? Most of it should be since the rock layers spanned from 10 million years ago to 15,000 years ago.

And another thing, why would it erode down to the basalt layer, and no deeper and no higher? Basalt and the the rocks above that are all solid rock. Why would there be any distinction of the basalt layer with any of the other rock strata above it?

There is only one reasonable explanation in my mind. The layers on top of the basalt were not solid rock when the flood occurred, but loose dirt. And if it was wet loose dirt then it would be even more plausible. So, the flood eroded the loose dirt and stopped the erosion at the solid rock underneath, the basalt layer.

This also is more consistent with all the curves we see from the erosion in the entire area.


https://hugefloods.com/Scablands.html

If the flood occurred over a flat surface of solid rock, we would not expect such curved patterns, but more of a straight shot erosion pattern.

Also note in the two photos above, there are columns in the middle of the eroded areas. Even if water could erode hundreds of feed of solid rock in several days, it should not leave those columns standing there.

[otseng]

Some more photos to illustrate my points.

Again, rushing water strong enough to erode hundreds of feet of solid rock should not leave columns of rock in the middle of the erosion area like this:




http://www.iinet.com/~englishriver/Lewi ... loods.html

And an on rush of water to rapidly erode solid rock should also not exhibit such curves during erosion:

[otseng]

The Wallula Gap was one of the deepest places during the flood. It is estimated to have been 1250 feet deep.
http://www.iinet.com/~englishriver/Lewi ... loods.html

In the image below, we see erosion all the way to the top of the gap:



Yet, it was also one of the narrowest points in which the flood flowed through:



Though I haven't seen anyone propose this, I theorize that Wallula Gap was created during the flood. Water had filled up the entire area of the Channeled Scablands north of Wallula Gap. And Wallula Gap was not a gap at all, but a dam that held all the water back. Then the water pressure eventually broke through the mountain and created Wallula Gap.

If we look at the area of the Channeled Scablands, it looks like the entire area was a giant lake, then the lake got unplugged at Wallula Gap. As the water receded, it caused the curved erosion patterns we see now.

So, the Channeled Scablands was not caused by an ice dam and the Missoula Flood, but rather, a lake dam failure where it broke through at the Wallula Gap.

[otseng]

It's typically explained that Wallula Gap existed for at least 10 million years.

"Early in the history of folding, the ridgecrest here was slightly lower than elsewhere along the ridge. This caused first the ancient Salmon-Clearwater River (precursor to the Snake River), and then the Columbia River to flow across the ridge over this low point. As the ridge continued to bend upward, river erosion kept pace, and a water gap developed. Until about 10 million years ago only the ancestral Salmon-Clearwater River flowed through Wallula Gap. It wasn't until about 6 million years ago that the Columbia River joined in, where it has continued to flow ever since. Somewhere between 2 and 3 million years ago, the ancestral Salmon-Clearwater River captured the Snake River in the vicinity of Hell's Canyon, along the Idaho-Oregon border; this added significantly to the amount of water draining through the gap."

http://www.iinet.com/~englishriver/Lewi ... a_gap.html

But, if the gap existed for millions of years, how did the stratas form on the cliffs of the gap?

If my theory is correct, then it can be confirmed by verifying that the stratas on each side of the gap match the other side. And if this is so, this would be proof that Wallula Gap was created during the flood. If the gap existed for millions of years, there would be no way that each side of the gap would have identical stratas. But, it would mean that all the stratas were laid down, then the gap was created after all the layers were formed.

[otseng]

Here is another problem I see with the ice dam theory.

The flood was supposedly strong enough to erode hundreds of feet deep of solid rock. When it approached Wallula Gap, all the water in the flood had to funnel through this small passage, yet it was only able to erode it one mile wide. It should've eroded it at least as wide as Grand Coulee Canyon, which is 5 miles wide.

Further, the flood was hitting the gap head on. You would expect water to more rapidly erode what it pushes than what it flows over. How could a mountain that was in the direct path of the flood be impacted so little, while at the same time hundreds of feet of solid rock under the flood be so easily eroded?

[jwu]

I kind of fail to see the relevance to E/C...

There is only one reasonable explanation in my mind. The layers on top of the basalt were not solid rock when the flood occurred, but loose dirt. And if it was wet loose dirt then it would be even more plausible. So, the flood eroded the loose dirt and stopped the erosion at the solid rock underneath, the basalt layer.

I suppose it is not proposed that layers of massive basalt were eroded away, rather sandstone or something like that.

Besides...as far as i know this is not thought to be the result of a single large flood, but several recurring events

Also note in the two photos above, there are columns in the middle of the eroded areas. Even if water could erode hundreds of feed of solid rock in several days, it should not leave those columns standing there.

...and exactly those columns support that. While a single large event would have crushed them, a series of smaller events which each is responsible for only a fraction of the erosion could leave them.

Though I haven't seen anyone propose this, I theorize that Wallula Gap was created during the flood. Water had filled up the entire area of the Channeled Scablands north of Wallula Gap. And Wallula Gap was not a gap at all, but a dam that held all the water back. Then the water pressure eventually broke through the mountain and created Wallula Gap.

If we look at the area of the Channeled Scablands, it looks like the entire area was a giant lake, then the lake got unplugged at Wallula Gap. As the water receded, it caused the curved erosion patterns we see now.

So, the Channeled Scablands was not caused by an ice dam and the Missoula Flood, but rather, a lake dam failure where it broke through at the Wallula Gap.

That doesn't make much sense to me. Exactly those things which you listed as supposed evidence against the ice dam theory apply to that scenario all the more.
E.g. if a breaking ice dam would have eroded those pillars away, then a draining global deluge wouldn't have left a piece of them either.

And of course those erosion patterns have nothing to do whatsoever with the question what actually held back the water until it was released.

But, if the gap existed for millions of years, how did the stratas form on the cliffs of the gap?
[...]
If the gap existed for millions of years, there would be no way that each side of the gap would have identical stratas.

What is the problem? Strata usually develop over a large area. A river or drainage can cut into it and leave identical strata on both sides of the canyon. I don't see any problem there, and i also fail to see how a global deluge is supposed to be any better as an explanation - if there is a problem, then it should be affected equally by it.

How could a mountain that was in the direct path of the flood be impacted so little, while at the same time hundreds of feet of solid rock under the flood be so easily eroded?

Huh? If i read your material correctly, then it appears like it was affected a lot - in the depth.