Geologist investigates canyon carved in just three days in Texas flood

Jun 20, 2010
This is an aerial photograph taken near the time of the 2002 flood event at Canyon Lake, Texas. Floodwaters overflowed Canyon Lake reservoir and carved the gorge downstream. Credit: Comal County, Texas.

In the summer of 2002, a week of heavy rains in Central Texas caused Canyon Lake -- the reservoir of the Canyon Dam -- to flood over its spillway and down the Guadalupe River Valley in a planned diversion to save the dam from catastrophic failure. The flood, which continued for six weeks, stripped the valley of mesquite, oak trees, and soil; destroyed a bridge; and plucked meter-wide boulders from the ground. And, in a remarkable demonstration of the power of raging waters, the flood excavated a 2.2-kilometer-long, 7-meter-deep canyon in the bedrock.

According to a new analysis of the and its aftermath—performed by Michael Lamb, assistant professor of geology at the California Institute of Technology, and Mark Fonstad of Texas State University—the formed in just three days.

A paper about the research appears in the June 20 advance online edition of the journal Nature Geoscience.

Our traditional view of deep river canyons, such as the Grand Canyon, is that they are carved slowly, as the regular flow and occasionally moderate rushing of rivers erodes rock over periods of millions of years.

Such is not always the case, however. "We know that some big canyons have been cut by large catastrophic flood events during Earth's history," Lamb says.

Unfortunately, these catastrophic megafloods -- which also may have chiseled out spectacular canyons on Mars—generally leave few telltale signs to distinguish them from slower events. "There are very few modern examples of megafloods," Lamb says, "and these events are not normally witnessed, so the process by which such erosion happens is not well understood." Nevertheless, he adds, "the evidence that is left behind, like boulders and streamlined sediment islands, suggests the presence of fast water"—although it reveals nothing about the time frame over which the water flowed.

These are boulders transported by the 2002 flood. Credit: Courtesy of Michael Lamb/Caltech

This is why the Canyon Lake flood is so significant. "Here, we know that all of the erosion occurred during the flood," Lamb says. "Flood waters flowed for several weeks, but the highest discharge—during which the bulk of the erosion took place—was over a period of just three days."

Lamb and Fonstad reached this conclusion using aerial photographs of the region taken both before and after the flood, along with field measurements of the topography of the region and measurements of the flood discharge. Then they applied an empirical model of the sediment-carrying capacity of the flood—that is, the amount of soil, rocks, boulders, and other debris carried by the flood to produce the canyon.

The analysis revealed that the rate of the canyon erosion was so rapid that it was limited only by the amount of sediment the floodwaters could carry. This is in contrast to models normally applied to rivers where the erosion is limited by the rate at which the underlying rock breaks and is abraded.

The researchers argue that the rate of erosion was rapid because the flood was able to pop out and cart away massive boulders (a process called "plucking")—producing several 10- to 12-meter-high waterfalls that propagated upstream toward the dam, along with channels and terraces. The flood was able to pluck these boulders because the bedrock below the soil surface of the valley was already fractured and broken.

The abrasion of rock by sediment-loaded waters—while less significant in terms of the overall formation of the canyon—produced other features, like sculpted walls, plunge pools at the bases of the waterfalls, and teardrop-shaped sediment islands. The sediment islands are particularly significant, Lamb says, because "these are features we see on Earth and on Mars in areas where we think large flow events have occurred. It's nice that here we're seeing some of the same features that we've interpreted elsewhere as evidence of large flow events."

The results, Lamb says, offer useful insight into ancient megafloods, both on Earth and on Mars, and the deep canyons they left behind. "We're trying to build models of erosion rates so we can go to places like Mars and make quantitative reconstructions of how much water was there, how long it lasted, and how quickly it moved," Lamb says. In addition, he says, "this is one of a few places where models for canyon formation can be tested because we know the flood conditions under which this canyon formed."

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yyz
5 / 5 (9) Jun 20, 2010
"Our traditional view of deep river canyons, such as the Grand Canyon, is that they are carved slowly, as the regular flow and occasionally moderate rushing of rivers erodes rock over periods of millions of years."

I wonder how long before the Texas Board of Education and Young Earth Creationists (same thing, really) point to legitimate research such as this as further proof that Earth "might be" 6,000 years old? We'll know soon enough.
Shootist
Jun 20, 2010
This comment has been removed by a moderator.
Scalziand
not rated yet Jun 20, 2010
Mini documentary on the Canyon Lake gorge:
http://www.youtub...BI96nYsE
Andragogue
5 / 5 (3) Jun 20, 2010
Young Earth Creationists will not doubt cherry pick bits of data from this study thereby adding to the volume of their pseudoscientific books and pamplets sold in gift shops around the Grand Canyon. (At 7 meters in 3 days, that's about 230 days to carve out the Grand Canyon.)
GaryB
5 / 5 (3) Jun 21, 2010
Unfortunately, these catastrophic megafloods -- which also may have chiseled out spectacular canyons on Mars—generally leave few telltale signs to distinguish them from slower events.


Is Lamb a young earth creationist?? There are plenty of signs: Slow erosion such as formed the Grand canyon leaves a meandering canyon when the earth rises under a meandering stream. Fast floods tend to leave straight paths.
GaryB
3 / 5 (2) Jun 21, 2010
> Unfortunately, these catastrophic megafloods -- which also may have chiseled out spectacular canyons on Mars—generally leave few telltale signs to distinguish them from slower events.

Is Lamb a young earth creationist?? There are plenty of signs: Slow erosion such as formed the Grand canyon leaves a meandering canyon when the earth rises under a meandering stream. Fast floods tend to leave straight paths.
Caliban
3.4 / 5 (5) Jun 21, 2010
Unfortunately for the YEC crowd, the total volume of material excision that is represented by the Grand Canyon will defy all but the most idiotic or foolhardy among them.
I don't have exact figures, but the discharge flow/volume rate of moving water required to carve out the canyon, on young earth timescales simply doesn't exist, and there is no documented megaflood precedent that could even come close to camparing- and even at that at least a couple orders of magnitude too small.
The Grand Canyon simply dwarfs any of the other megaflood sites- Washington state's Channeled Scab Lands, the English Channel, and the McKenzie River megaflood features, after repeated episodes, are HUGE- but still tiny in comparison to the Grand Canyon.
Caliban
3.4 / 5 (5) Jun 21, 2010
I did some digging- the Lake Missoula floods, responsible for the Channeled scab lands, et c, and amounting to a total of ~20,000 cubic miles of water, in a series of as many as 40 drainage events, only removed an estimated 50 cubic miles of material.

These events hold the record for peak discharge rate fo any known megaflood events. The Lake Agassiz/McKenzie River event, while of considerably greater total volume,(~6,000 cubic miles in one event) discharged over a wider x-section, and greater distance.

By comparison, the volume of material removed from the Grand Canyon-conservatively- is ~2600 cubic miles. About 5 orders of magnitude greater.

A megaflood is pretty much out of the running as the agency of Grand Canyon formation- although I have heard that theory advanced, and recently at that. But now you've got some numbers to use to refute any such assertion.
Ethelred
5 / 5 (5) Jun 21, 2010
There is a simple way to show that the Grand Canyon was not created by a single great flood.

The North Rim of the Grand Canyon is 2000 feet higher than the South Rim. The Colorado River flows mostly west with a little bit of south. Across the slope. Not along it.

As single great flood would have flowed SOUTH towards the Gulf of Mexico instead of west towards the Gulf of California. Pointing this out has invariably stopped YEC in their tracks for me. Some have even bothered to ask why the Colorado flows the way it does. Thus showing signs that they might have actually begun to think.

Ethelred
Caliban
2.3 / 5 (3) Jun 21, 2010
@ER
So, this provides a minimum of two methods to refute YEC floodform Grand Canyon.
Shootist
3.4 / 5 (5) Jun 21, 2010
Why worry about refuting Young Earthers? That is about as challenging as refuting Flat Earthers or astrology.

EdMoore
3 / 5 (3) Jun 21, 2010
Nice article. I especially like the fact that catastrophic processes were so ignored and denied in the past, and now they are solidly on the table for consideration. I'm sorry this makes some people nervous, but these white rabbits need to be followed.
Shootist
3 / 5 (4) Jun 21, 2010
Well, this ditch is rather more microstrophic than catastrophic.

The planet get whacked every 100,000 years, or so, by a 500m to 1km diameter bolide. THAT is catastrophic.

Skeptic_Heretic
3.7 / 5 (3) Jun 21, 2010
I don't have exact figures, but the discharge flow/volume rate of moving water required to carve out the canyon, on young earth timescales simply doesn't exist,
I have the figures. The water would have had to have been moving fast enough to travel the whole length of the canyon in 5 minutes and continue for a period of 230 to 250 years. Effectively that would be more water than we have in the Gulf of Mexico channeled like a steel cutter down a snaking river path.
Shootist
3.4 / 5 (5) Jun 21, 2010
Nice article. I especially like the fact that catastrophic processes were so ignored and denied in the past, and now they are solidly on the table for consideration. I'm sorry this makes some people nervous, but these white rabbits need to be followed.


Don't drink too much of that kool-aid, chief.

It is true that as more remote sensing is used, more large scale Earth changes (Sudbury, Vredefort) become apparent. However, catastrophic, meaning quick, earth changing events, have long been accepted in Earth Science. It is the scale of these changes (how large, how often) that has been subject to debate.

See:

Scab Lands Lat 47.451031° Lon -119.150672°
Lake Agassi southern outflow Lat 45.950840° Lon -91.838461°

Both of these areas have been recognized, as having been subject to catastrophic change, for nearly 100 years.

Whereas the large impact craters, Sudbury and Vredefort have only been accepted as astroblemes for several decades.
Scalziand
5 / 5 (3) Jun 21, 2010
@ER
So, this provides a minimum of two methods to refute YEC floodform Grand Canyon.


A third possible method would be examining the sediment deposition patterns at the Colorado river delta. If the sediments are graded into many different layers, it suggests that the canyon formed slowly over time. If the sediments are in one giant layer, then it would suggest that the canyon was formed in one event.
tkjtkj
3 / 5 (2) Jun 21, 2010
"The flood was able to pluck these boulders because the bedrock below the soil surface of the valley was already fractured and broken."


'Fractured bedrock'? i dare say there is no such animal. Bedrock is bedrock ..solid .. If its fractured, it is not bedrock ..hence: bedrock was not mobilized.

Is this fellow really a scientist? If so, i recommend wikipedia.org to him.

in7x
5 / 5 (2) Jun 21, 2010
The Grand Canyon was carved by the recession of Noah's flood. It's true; says it right here in my textbook.
Skeptic_Heretic
2.3 / 5 (3) Jun 21, 2010
The Grand Canyon was carved by the recession of Noah's flood. It's true; says it right here in my textbook.
It is such sad commentary that although you said it in jest, it's probably true.
Scalziand
not rated yet Jun 21, 2010
'Fractured bedrock'? i dare say there is no such animal. Bedrock is bedrock ..solid .. If its fractured, it is not bedrock ..hence: bedrock was not mobilized.

Is this fellow really a scientist? If so, i recommend wikipedia.org to him.



It appears that the correct term for rock that has been cleaved from the bedrock but hasn't moved is 'subcrop'.
http://jersey.uor...y36.html
Caliban
2.3 / 5 (3) Jun 21, 2010
@Scalziand,

I think that you may have drifted into the hair-splitting zone, at least a little. Bedrock and subcrop are, indeed, terms that reflect more than a little relativism.

For instance- in the case of the Lake Missoula floods- when "boulders" are mentioned, they aren't really talking about a 5 ton rock- they're talking about a hunk the size of a couple houses, and weighing a few hundred to few thousands of tons(or more!), so there is quite a difference in scale.

The greater the scale, the less likely that the bedrock will be entirely free of fractures, faults, chemical degradation from aqueous infiltration et c., so it really is relative, and what is usually meant by subcrop is pieces on a much smaller scale in terms of size/weight- more in line with what you would call scree or talus.

Judy_Hobrecht
2 / 5 (8) Jun 21, 2010
It's kind of hilarious watching you folks try to discredit young earth ideologists. The fact is there is still MEGAKNOWLEDGE that is not known, not understood, or not even available at this time in history.

You people have no clue what event created the Grand Canyon or any other canyon because you didn't witness it, and neither did anybody else.

The fact is that even the continents have come together and separated and you haven't a clue when that happened or why it happened. And what is seen with the human naked eye in the universe happened light years ago. And you STILL haven't a clue what is happening.

However you will continue to arm chair scientist the the slim to none facts available to you and declare it as facts which are no more credible than the young earth ideologists.

Very very amusing to watch when observing human behavior.
Caliban
3 / 5 (4) Jun 21, 2010

MEGAKNOWLEDGE. I gotta get me some of that! Where are you keeping it, Judy?

I gave you five stars, 'cause you're funny!
C2020
1 / 5 (4) Jun 22, 2010
The North Rim of the Grand Canyon is 2000 feet higher than the South Rim. Pointing this out has invariably stopped YEC in their tracks for me.
Ethelred


I appreciate your thoughts on this but your comments seem to be a reaction to any scientific explanation that might suggest the YEC crowd has some intelligence. There are some that believe the Grand Canyon was formed as a consequence of a dam breach failure. Please see Fenton, C.R., Webb, R.H. and Cerling, T.E. (2006) "Peak discharge of a Pleistocene lava-dam outburst flood in Grand Canyon, Arizona, USA" Quaternary Research, Volume 65, Issue 2, March 2006, Pages 324-335 for a discussion on their unsteady dam breach analysis proposal. The dam in this case would be the ridge running roughly north-south in orientation and generally associated with Rt67 on the north and Rt64 on the south - near Lookout Tower.

-Brevity may be the soul of wit, but not science- one more brief installment...
Ethelred
4.2 / 5 (5) Jun 22, 2010
The fact is there is still MEGAKNOWLEDGE that is not known, not understood, or not even available at this time in history.
Which in know way equates to having enough knowledge right now to exceedingly certain that the world is billions of old and not less than ten thousand.
You people have no clue what event created the Grand Canyon
Just because YOU are ignorant does not mean that the rest of us are. We have a sound understanding of the geology of the Grand Canyon. It was not AN event. The fact that its an entrenched meander means that it HAD to have been cut over a long VERY long period of time.
Very very amusing to watch when observing human behavior
Indeed and thank you for amusing us with your protestions of ignorance that is mostly yours. A strange first post on a science site. But not at all strange for a hit and run YEC post on ANY site.

Please be different. Don't do the run part. Stay and learn a little. Ignorance is curable IF you are willing.

Ethelred
Caliban
3 / 5 (4) Jun 22, 2010
-Brevity may be the soul of wit, but not science- one more brief installment...


@C2020,

Of course it's appreciated that you went to the trouble to cite a hypothesis, even if it doesn't hold water. Many theories have been proposed and rejected. You may, next time, actually provide a link, instead of a simple citation.

There is, to put it bluntly, no evidence for a body of water of the extent requisite to have carved out the GC in a catastrophic megaflood or series of megafloods. The events to which you refer were on the order of "drop in the bucket" magnitude, involving only a few cubic miles of impounded water per episode, and at that, only a maximum of five times by best information, for a TOTAL discharge of maybe as much as 50 cubic miles of water.

Look at the numbers from my first post, and you can see that there are several orders of magnitude separating the events you write about, and the force needed to carve out the Grand Canyon.
Ethelred
5 / 5 (3) Jun 22, 2010
I appreciate your thoughts on this but your comments seem to be a reaction to any scientific explanation that might suggest the YEC crowd has some intelligence
I was talking about a method of pointing out errors in thinking where YEC have ACTUALLY noticed that I might have had a point. A real, tried and tested tactic for getting past active ignorance. Of course it doesn't always work but the point is that sometimes it does.

Most YEC are ignorant because they were kept that way. Some are still capable of thinking. They simply have only seen one side of the discussion.
There are some that believe the Grand Canyon was formed as a consequence of a dam breach failure.
A single catastrophic event cannot create an entrenched meander. Those result in things like the Scablands. A partial breach that collapses over an extended period of time could do a lot of cutting without creating something like the Scablands but it can't create the Grand Canyon as a whole.

Ethelred
Skeptic_Heretic
4.2 / 5 (5) Jun 22, 2010
It's kind of hilarious watching you folks try to discredit young earth ideologists.
There is no try padawan, only do or do not. We do, they do not.
The fact is there is still MEGAKNOWLEDGE that is not known, not understood, or not even available at this time in history.
Right, compared to a statement of absolute certainty that the world was created by a being that required no creator through a golem spell.

The fact is that even the continents have come together and separated and you haven't a clue when that happened or why it happened.
Wrong. Your ignorance isn't our ignorance.
And what is seen with the human naked eye in the universe happened light years ago.
Light years are not a measurement of time.
And you STILL haven't a clue what is happening.
Actually we have several clues, conincidentally these clues soundly disprove the YEC "hypothesis".
C2020
1 / 5 (2) Jun 23, 2010
-continued: The Quaternary Research article is a "for purchase" item, but a layman's look at the concept is given by Fenton, et al at http://www.gcrg.o...va.html. I believe their proposal does not require failure of the entire corridor but is instead related to lava flow plugging of the corridor and subsequent failure with scouring and downstream deposition of flood sediments.

Dam failures are not simple, especially when trying to reconstruct such events with only the "accident skid marks" available for review.

Further, the drainage basin of the Colorado is 140,000 square miles at Grand Canyon. Even a small percentage of impoundment over this area can represent thousands of cubic miles of water. Also, the topography does not demand flood flows to the south, even for larger events. The southern ring of national forest(s) from Kaibab to Cibola appear high enough, especially if some form of channel exists and the failure is seepage driven through weak strata.
Ethelred
5 / 5 (3) Jun 23, 2010
The flood you linked to occurred within the existing Grand Canyon. It makes that quite clear in your link.

Dam flood cannot create an entrenched meander. Sure they can increase the depth of the canyon and maybe even knock a few corner out some of the meanders.

So whats your point? Are you just pointing that flood occurred within the Canyon or are you claiming that a flood that occurred 165,000 years ago somehow makes the Canyon 4,400 years old?

In other words was that a YEC post? After all the two are your first posts. Which could be why your point isn't clear. The reason for the lack of clarity from YECs is tendency for YECs to pretend they are being reasonable by avoiding being honest about there intentions.Such as Judy_Hobrecht's, so far, hit and run posts looks to be.

Ethelred
C2020
2.3 / 5 (4) Jun 23, 2010
@Ethelred
It always comes back to worldviews, no matter how much the comment guidelines desire otherwise. If one appears as a YEC, he can be tagged and ridiculed. If one is simply trying to advance the knowledge of hydraulics, regardless of worldview or where the inquiry leads, it makes some folks nervous as you yourself state. The original post was simply a reference to the possibility of significant historic dam breach failures of a scale not well understood today.

Further, analysis of a breach failure forming the Grand Canyon, however remote a possibility, is difficult because it involves significant cross-disciplinary understanding. As I stated in my last post, we do not know what the original corridor looked like, nor what geologic weaknesses may have existed. Your demand for a linear failure may be inconsistent with the original topography and rock/soil considerations. Refusing science because it supports a conclusion also supported by YEC is the way of error.
Skeptic_Heretic
3.7 / 5 (3) Jun 23, 2010
If one appears as a YEC, he can be tagged and ridiculed.
If you object to this I'd like to know why.
Caliban
3 / 5 (4) Jun 23, 2010
@Ethelred
It always comes back to worldviews, no matter how much the comment guidelines desire otherwise.(...) Refusing science because it supports a conclusion also supported by YEC is the way of error.


There- you've said it yourself, C2020. I've altered the context slightly, but you've highlighted the essential difference between the Scientific Method, and pseudoscientific mythology- in this case, the YEC fiction.
Rather than letting the facts speak for themselves, and either support or modify, or invalidate an hypothesis as is normaly the case in scientific investigation, YEC begins with the assumption -a priori- of divine creation, and then seeks to FIT facts -by force or distortion if necessary- to that assumption.

You have, in this case, tried to make a "mountain" of a "molehill"-scale event.

I had to do a backdoor search to get at a summary of the details of the study you cited, but was nevertheless able access it. CONT'D
Caliban
3 / 5 (4) Jun 23, 2010
So, now I will repeat- it nowhere supports the scale of action necessary to have formed a feature the size and extent of the Grand Canyon. And this aside from consideration of any other possible cause or causes of its formation.

At the same time, you pretend(?) to not be a YEC supporter; but rather a person who is interested solely in the truth, when any reasonable person could see-based on the data contained in that report- that it doesn't support the YEC hypothesis at all.

In effect, you've shot yourself with your own gun. TWICE! Your article is wholly lacking in any merit as support for the YEC myth(specifically in regard to the Grand Canyon being an example), and is, at the same time, insufficient to support a CATASTROPHIC event as the cause of its formation, which you advanced as the straw man to cover the YEC thrust of your "argument".

Believe what you want, but to go toe-to-toe in scientific terms, you need MASSIVE FACTS, man!
Ethelred
5 / 5 (3) Jun 24, 2010
If one appears as a YEC, he can be tagged and ridiculed.
If one WRITES like a YEC on a science site then one will rebutted. Besides you handle looks suspiciously like a reference to the Great Flood. Interestingly enough that date places the flood in middle of the Egyptian pyramid era. Somehow the Egyptians didn't notice being drowned.
it makes some folks nervous as you yourself state.
Who is nervous? I have been debating YECs, and I mean REALLY debating not snickering at, for close to a decade.
significant historic dam breach failures of a scale not well understood today.
Actually, they are pretty well understood. They simply aren't known by all. Perhaps you just came across them recently.

Continued
Ethelred
5 / 5 (4) Jun 24, 2010
is difficult because it involves significant cross-disciplinary understanding
Actually its difficult because such a flood CANNOT form an entrenched meander. Such floods cover large areas and overflow existing rivers thus washing away all signs of the original riverbeds.
Your demand for a linear failure
I did no such thing. I said that a breach can't FORM a meander. If the meander was already there then the bends would be overrun UNLESS they where already so deep as to be rather similar to todays Grand Canyon. How meanders are formed is well understood. They only form in SLOW rivers such as the Mississippi or the MEANDER which where the word comes from.
Refusing science because it supports a conclusion also supported by YEC is the way of error.
Rebutting wild assed speculation that defies known laws is the way of reason.

The total lack of evidence for the Great Flood is a world wide un-phenomena. There should be evidence EVERYWHERE. At every level of science.

Ethelred
yyz
5 / 5 (3) Jun 24, 2010
I remember studying the formation of meanders and oxbow lakes back in my 6th grade Earth Science class. Pretty neat and not too hard to grasp. C2020 might want to explore the basics: http://en.wikiped.../Meander

"Believe what you want, but to go toe-to-toe in scientific terms, you need MASSIVE FACTS, man!"

And MEGAKNOWLEDGE! Don't forget MEGAKNOWLEDGE!

C2020
1 / 5 (1) Jun 24, 2010
Thank you for taking time out for discussion. My son initially showed me the above article because I am a professional engineer. Hydrology and hydraulics is what I do for a living, including dam breach analyses. I have witnessed flood events and their destructive power for storm events of less than annual to greater than 200-yr event magnitude.

It appears that you are constraining the problem through your worldview including inaccurate calculations for volume of rock/soil loss and impounding capacity driven by presupposition. The Colorado basin is a bowl with a single gash for an outlet at Grand Canyon. Marble Canyon looks like a sediment drawdown zone. If the basin stored water from receding glaciers or whatever source with failure from seepage and/or fault activity (Bright Angel), the initial failure could have simply stripped the surface 1000 ft with subsequent downcutting and meander development over subsequent years, regardless of your preference for a timeframe constraint.
Ethelred
5 / 5 (3) Jun 24, 2010
No matter what you claim you won't get meanders that way. Water has momentum. It will go straight. As in straight through oxbows UNLESS they already VERY deep and granite hard.

Even 1000 year floods will not cut down through all that sandstone and limestone and at the bottom gneiss except over millions of years. And 165,000 years ago the Canyon was likely already down to that metamorphic bedrock.

It has become a bowl via millions of years of erosion. Faults don't form meanders either so a fault can't be basis of the mile deep meanders in the Grand Canyon.

I have noticed that some engineers are quite capable of keeping the physics away from their beliefs. One engineer with a doctorate actually came up with with an exceeding ludicrous excuse for the geological problems with YEC.

He called it Hydroplate Theory. And it's not a theory nor even a wild assed guess since it is completely in denial of physics.

So are you a YEC or just trying to see what will stick?

Ethelred
Skeptic_Heretic
5 / 5 (2) Jun 24, 2010
the initial failure could have simply stripped the surface 1000 ft with subsequent downcutting and meander development over subsequent years, regardless of your preference for a timeframe constraint.

You're also ignoring the fact that not only do we see water erosion leading to the current shape of the grand canyon but we see the effects of severeal million years of wind and rain erosion that becomes progressively less pronounced as you reach the bottom of the canyon.

The Grand Canyon could not have come to be on short geological timescales. There isn't one piece of evidence refuting your statement, there are thousands of pieces of observational evidence that refute your "hypothesis".
ubavontuba
1.5 / 5 (8) Jun 25, 2010
the initial failure could have simply stripped the surface 1000 ft with subsequent downcutting and meander development over subsequent years, regardless of your preference for a timeframe constraint.

You're also ignoring the fact that not only do we see water erosion leading to the current shape of the grand canyon but we see the effects of severeal million years of wind and rain erosion that becomes progressively less pronounced as you reach the bottom of the canyon.

The Grand Canyon could not have come to be on short geological timescales. There isn't one piece of evidence refuting your statement, there are thousands of pieces of observational evidence that refute your "hypothesis".
References?

If you look at satellite images of this gorge, you can clearly see that it meanders. Furthermore, the water which remains in the gorge is meandering within the confines of the gorge. Therefore, it looks like the meandering erosion argument is rather weak.
ubavontuba
1.6 / 5 (8) Jun 25, 2010
Interestingly, recent calcite deposit analysis have thrown long accepted estimates of the Grand Canyon's age out the window (it's apparently much older than previoulsy thought).

See: http://en.wikiped...#Geology

So, it seems we still have much to learn about canyon formation.
Skeptic_Heretic
5 / 5 (1) Jun 25, 2010
Are you asking me for references or the pster I'm replying to?
ubavontuba
1 / 5 (2) Jun 25, 2010
Are you asking me for references or the pster I'm replying to?
References from both would be nice.
Skeptic_Heretic
5 / 5 (1) Jun 25, 2010
http://teacher.sc...nyon.htm
http://www.ohrang...-geology

Here are two, there are more but they tend to be more general and speak to canyons in general. From my education typically the water flow from a stream or river cuts deeper while wind and rain, and the resultant mudslides and rock falls carve wider.
ubavontuba
1 / 5 (1) Jun 25, 2010
http://teacher.scholastic.com/dirtrep/erosion/canyon.htm

Here are two, there are more but they tend to be more general and speak to canyons in general. From my education typically the water flow from a stream or river cuts deeper while wind and rain, and the resultant mudslides and rock falls carve wider.
LOL! These are the best you can do? They're written for schoolchildren! Worse, what little data they provide has recently been called into question by the calcite analysis.

The Young Earthers had it bad enough explaining why their erosion rates don't lead to catastrophic silting during heavy storms (of Lake Mead, for instance), now it's even worse for them. The Grand Canyon appears to be about three times older than previously thought!

See: http://www.nytime...f=slogin
Skeptic_Heretic
not rated yet Jun 25, 2010
LOL! These are the best you can do? They're written for schoolchildren! Worse, what little data they provide has recently been called into question by the calcite analysis.
Like I said, there wasn't much online in my initial searches.

I'm unfamiliar with the calcite analysis you speak of, got a link?
ubavontuba
1 / 5 (1) Jun 25, 2010
LOL! These are the best you can do? They're written for schoolchildren! Worse, what little data they provide has recently been called into question by the calcite analysis.
Like I said, there wasn't much online in my initial searches.

I'm unfamiliar with the calcite analysis you speak of, got a link?
Yeah. There's one at the bottom of my previous post. Why do you keep missing them?
Skeptic_Heretic
not rated yet Jun 25, 2010
Yeah. There's one at the bottom of my previous post. Why do you keep missing them?

No, I caught that, I was referring to an underlying paper published to that effect. You have provided a good start on my inquiry though.
ubavontuba
1 / 5 (1) Jun 25, 2010
Yeah. There's one at the bottom of my previous post. Why do you keep missing them?

No, I caught that, I was referring to an underlying paper published to that effect. You have provided a good start on my inquiry though.
Well if you want the official scientific publication, it can be found here:

http://www.mmjb.i...868/1377
yyz
4.3 / 5 (3) Jun 25, 2010
ubavontuba,

The original discussion here was that the Grand Canyon could not have been formed in less than 10,000 years, as YEC contend. You yourself pointed out that this new, older estimate for the creation of the GC made the YEC position even more untenable. But you go on to note:

"If you look at satellite images of this gorge, you can clearly see that it meanders. Furthermore, the water which remains in the gorge is meandering within the confines of the gorge."

You then add the non sequitur:

"Therefore, it looks like the meandering erosion argument is rather weak." How so?

The new study you link to finds the GC age older than previously thought, but in NO way supports your contention that the meandering erosion argument is weak.

From your link:

"The results indicated that the erosion rate was much slower in the western canyon than in the eastern section"

So the GC is older than previous estimates AND was formed by erosion. Check your sources.

yyz
5 / 5 (4) Jun 25, 2010
Again, from the NYT link:

"By dating mineral deposits inside caves up and down the canyon walls, the geologists said they determined the water levels over time, as erosion carved out the mile-deep canyon as it is known today."

So again, the GC is older than previously thought (and immaterial to this discussion) AND the GC was formed by erosion.
ubavontuba
1 / 5 (1) Jun 25, 2010
@yyz,

I'm only saying the argument that quick erosion must be in straight paths is not a good argument. And, I'm providing a better argument for the age of the Grand Canyon.

Seriously, do you think that (sooner or later) the Young Earthers aren't going to look at the satellite images themselves?
yyz
5 / 5 (3) Jun 25, 2010
I don't know if examination of satellite images by Young Earthers is going to settle anything. They've already "found" Noahs Ark on satellite images o_O
Caliban
3.8 / 5 (4) Jun 25, 2010
@yyz,

I'm only saying the argument that quick erosion must be in straight paths is not a good argument. And, I'm providing a better argument for the age of the Grand Canyon.


The argument of "Straight Path" erosion, as you put it, is a non-argument, which is entirely the point.

Catastrophic flooding does, indeed, tend to have a "straightening" effect. Therefore, for it to have been the primary cause of the Grand Canyon's formation -over ANY timescale- the canyon would be suspiciously lacking in meander- which would be a PRIME INDICATOR of catastrophic origin.

I think what you really mean to say, is that this calcite age-of-formation study can establish the age of the Grand Canyon, without any reference to the physical mechanism(s), other than clearly, water itself, and thereby vitiate the YEC catastrophic formation hypothesis.

Well- there we have it- THREE simple refutations to the YEC hypothesis.
ubavontuba
1.6 / 5 (5) Jun 25, 2010
The argument of "Straight Path" erosion, as you put it, is a non-argument, which is entirely the point.

Catastrophic flooding does, indeed, tend to have a "straightening" effect. Therefore, for it to have been the primary cause of the Grand Canyon's formation -over ANY timescale- the canyon would be suspiciously lacking in meander- which would be a PRIME INDICATOR of catastrophic origin.

I think what you really mean to say, is that this calcite age-of-formation study can establish the age of the Grand Canyon, without any reference to the physical mechanism(s), other than clearly, water itself, and thereby vitiate the YEC catastrophic formation hypothesis.

Well- there we have it- THREE simple refutations to the YEC hypothesis.
Generally correct, except that I would say that like electricity, water will seek the path of least resistance to achieve its minimum potential (lowest possible elevation). This path can meander, much like lightening meanders in the atmosphere.
ubavontuba
1.8 / 5 (5) Jun 25, 2010
I don't know if examination of satellite images by Young Earthers is going to settle anything. They've already "found" Noahs Ark on satellite images o_O
LOL. However, why argue from an essentially untenable position? Stronger arguments make better arguments.
Ethelred
5 / 5 (2) Jun 26, 2010
I'm only saying the argument that quick erosion must be in straight paths is not a good argument.
It is, at least as I originally stated it. If you can find a way to force water to go in non-straight lines in SOFT meanders, as exist in non-entrenched rivers, then you will have a point. Not till then.

Are you aware that YECs claim the whole thing including the sedimentation was created in the flood?
And, I'm providing a better argument for the age of the Grand Canyon.
No. You are providing radioactive dating and YECs laugh at such dates. Laughing is about the limit most of the time. Then comes the polonium if they are more skilled. Based on experience the fact that the plateau slopes generally southwards seems to work best.
Seriously, do you think that (sooner or later) the Young Earthers aren't going to look at the satellite images themselves?
They aren't interested in actual evidence. They are looking for ways to avoid it.

Ethelred
Skeptic_Heretic
5 / 5 (3) Jun 26, 2010
LOL. However, why argue from an essentially untenable position? Stronger arguments make better arguments.

Because fraudsters like Kent Hovind exist and use pseudoscience to poison the well of impressionable people's minds to reap a profit. Just like that loser Andrew Wakefield, who is basically responsible for the pertussis epidemic in Calfornia.
Ethelred
3.7 / 5 (3) Jun 26, 2010
Skeptic, there is no reason to argue from a poor position. Unless that is all you have. Like the YECs have.

As far as I can tell ubavontuba simply hasn't discussed this stuff with YECs much so he doesn't understand their position on the Grand Canyon. They aren't going to claim that the meanders were there already. Not normally anyway. Even c2020 wasn't claiming the meanders were there already. He was claiming weakness in the landscape that, by magic, produced and an exact replica of a meandering slow river like the Mississippi. Faults don't work that way.

Ethelred
ubavontuba
1.4 / 5 (5) Jun 26, 2010
@Ethelred,

Hydrology doesn't work that way. Straight channels are inherently unstable. In straight channels (almost always manmade) water gouges out the bottoms, creates pools, undermines banks & levies, and, if left alone long enough, eventually develops meanders.

The general rule is: The wider the flow, the bigger the meanders, but water won't naturally flow straight.

See: http://en.wikiped.../Meander

and: http://www.britan...channels

and: http://www.nahann...?page=18

and even: http://www.astrob...-of-mars

Of course it would take awhile for Young Earthers to figure this out, but there are some smart ones that eventually would - irreparably damaging your arguments. Why give them the opportunity?
ubavontuba
1.8 / 5 (5) Jun 26, 2010
LOL. However, why argue from an essentially untenable position? Stronger arguments make better arguments.

Because fraudsters like Kent Hovind exist and use pseudoscience to poison the well of impressionable people's minds to reap a profit. Just like that loser Andrew Wakefield, who is basically responsible for the pertussis epidemic in Calfornia.
I hope you're not saying it's okay to use a fraudulent argument to fight a fraudulent argument!

The pertussis epidemic, you mention, certainly is a sad commentary on bad science...
ubavontuba
1.8 / 5 (5) Jun 26, 2010
Skeptic, there is no reason to argue from a poor position. Unless that is all you have. Like the YECs have.

As far as I can tell ubavontuba simply hasn't discussed this stuff with YECs much so he doesn't understand their position on the Grand Canyon. They aren't going to claim that the meanders were there already. Not normally anyway. Even c2020 wasn't claiming the meanders were there already. He was claiming weakness in the landscape that, by magic, produced and an exact replica of a meandering slow river like the Mississippi. Faults don't work that way.

Ethelred
I think U-Pb dating is a well established science. However, even an uneducated fool knows it takes time to build up these calcite deposits in the first place. It simply wouldn't exist in the higher caves if the water gouged out the channel rapidly.
C2020
1 / 5 (1) Jun 26, 2010
To jump back into the fray, my interest is not your preference for dating philosophy but the mechanics of dam breach failure itself. It is clear from current research that we still do not have a precise understanding of scour and dam breach failure or we would not presently be researching those topics. See the Teton dam failure (roughly 1/10 scale height of what we are considering here - http://ponce.sdsu...s.html). Please notice the sediment laden condition of the water during and subsequent to failure.
C2020
1 / 5 (1) Jun 26, 2010
As to meanders, a presentation of scale would probably be helpful. The downstream corridor to Lake Mead is about 150 mi. Using 3000 ft of elevation change, which is 20 ft/mi., we obtain a slope of 0.38% (which in stream hydraulics is somewhat steep for terminal, not headwaters conditions).

The scale would be similar to placing a 0.1cm pencil lead under one end of a 12-inch long glass plate. Now mix about 10+% very, very fine sand/silt mixture with water in a child's slotted sippy cup (we are looking for a flow path about 1/2-inch width and 0.05cm deep). Pour out at one end and tell me what resultant flow path is created by this process. The initial Colorado basin corridor would not have been quite as smooth.

Please also review the following for some understanding into the nature flow hydraulics in steep streams (this may not be 100% applicable to our situation but provides help in understanding stream flow) http://www.fsl.or...low.pdf.
ubavontuba
1.8 / 5 (5) Jun 26, 2010
To jump back into the fray, my interest is not your preference for dating philosophy but the mechanics of dam breach failure itself. It is clear from current research that we still do not have a precise understanding of scour and dam breach failure or we would not presently be researching those topics. See the Teton dam failure (roughly 1/10 scale height of what we are considering here - http://ponce.sdsu...s.html). Please notice the sediment laden condition of the water during and subsequent to failure.
Did the Teton Dam collapse leave any significant calcite deposits in the breach? No? Case closed.
Judy_Hobrecht
1 / 5 (5) Jun 26, 2010
And the facts still are, you have no clue how the Grand Canyon was formed, no matter how many times you attack me and call me ignorant. But again, it's funny to watch.

Ethelrod, you're just too cute, sir. Your science is purely speculative at this time. I know that fact upsets you, but there it is.
Baseline
5 / 5 (2) Jun 26, 2010
@Judy

Forgive my presence in the shadow of your MEGA-AWESOMENESS. I am truly humbled and frankly can not wait for your next words of enlightenment for those of us who simply believed we knew nothing but were willing to learn. You must imagine our embarrassment now that we learned that we have been wasting our time with school and books, not to mention all the money we have wasted on all those useless experiments and peer reviewed papers and such. All this time all we ever needed to do was to ask Judy. For heavens sake.

Baseline
5 / 5 (2) Jun 26, 2010
No, the thing that is truly upsetting is having to waste precious time and resources debating people who hold so dearly to their beliefs that they are unable to manifest an independent thought in the presence of overwhelming evidence that contradicts said beliefs.

If you are unwilling to accept new evidence or arguments that contradicts what you believe then you must believe you already know all the answers. Apparently that makes you not ignorant at all but indeed the most intelligent human being that has ever existed. I am truly in awe to be in your e-presence.
C2020
1 / 5 (1) Jun 26, 2010
@ubavontuba
"The study, which was published in the journal Science in 2008, utilized uranium-lead dating to analyze calcite deposits found on the walls of nine caves throughout the canyon." (your Wiki reference).

At what elevation are the nine caves where the studies were conducted? How many caves on the west side and how many on the east and elevations for each one? Also, what do the authors posit created the calcite deposits?
ubavontuba
1.8 / 5 (5) Jun 27, 2010
@ubavontuba
"The study, which was published in the journal Science in 2008, utilized uranium-lead dating to analyze calcite deposits found on the walls of nine caves throughout the canyon." (your Wiki reference).

At what elevation are the nine caves where the studies were conducted? How many caves on the west side and how many on the east and elevations for each one? Also, what do the authors posit created the calcite deposits?
Read the original paper. Here's a link: http://www.mmjb.i...868/1377
Ethelred
4 / 5 (4) Jun 27, 2010
Straight channels are inherently unstable. In straight channels
I didn't say otherwise. I said FLOODS of the sort involved in a dam break will straighten the meanders. UNLESS they are already well entrenched.

What part of that is wrong or hard to understand?
I think U-Pb dating is a well established science.
Of course it is. So the YECs make up lies and engage in fantasy to evade it.
However, even an uneducated fool knows it takes time to build up these calcite deposits in the first place.


You REALLY haven't had many discussions with YECs have you?

It simply wouldn't exist in the higher caves if the water gouged out the channel rapidly.


You are preaching to the choir. Despite all the evidence that has ever been produced the YECs still think EITHER the Grand Canyon was produced in the Great Flood 4,400 years ago OR Jehova made it look exactly the way it does. Apparently just to confuse the issue.

Ethelred
Ethelred
4 / 5 (4) Jun 27, 2010
To jump back into the fray, my interest is not your preference for dating
Well YOU are the one that replied to me in a way sure looked like an attempt to back up the YEC position. After all you seemed state that the YEC crowd had some science on their side. And intelligence which is something I have never denied. Lots of YECs are intelligent, they simply are ignorant. Either actively or through the actions of the people that raised them. That includes people other than just their parents.

What I originally said remains true. If the Grand Canyon was created by the Great Flood it would flow south. The rain that lands on the south side of the river flows south even now except for that which hits near the river.

Ethelred
Ethelred
3.7 / 5 (3) Jun 27, 2010
but the mechanics of dam breach failure itself


Which is reasonable but the way you wrote that first post it looked very much like an attempt to claim that the entire canyon was formed very recently. That dam breaches might have significantly contributed to the formation of the Canyon is in no a problem for me. The heaviest erosion in rivers comes from the unusual and not normal.

http://www.fsl.or...low.pdf.

Watch how you post links. They should be the only thing on the line no matter how long the line is. The period at the end broke the link.

Ethelred
Ethelred
4 / 5 (4) Jun 27, 2010
And the facts still are, you have no clue how the Grand Canyon was formed,
Which is dubious opinion and not in any way a fact. That I don't know everything is not an indication that I know nothing.
no matter how many times you attack me and call me ignorant.
It is true that the facts have no requirement to become real simply because I point out your lack of knowledge. But they don't go away either simply because you don't know them.
But again, it's funny to watch.
Well it is interesting to watch YECs act silly anyway.
Your science is purely speculative at this time. I know that fact upsets you, but there it is.


Why don't read a bit on it. I am not engaging in speculation. The evidence that the world is old is overwhelming. The evidence that the Canyon is vastly older than 4000 or so years is equally overwhelming. Simply claiming that it is speculation will not make it so. Only ignorance could produce a claim that it is mere speculation.

Continued
Ethelred
4 / 5 (4) Jun 27, 2010
Now if you want to actually SHOW some evidence that the Canyon is young or that I don't have a clue please feel free. I am always interested in seeing what new concepts, if any, a YEC can produce.

You couldn't possibly upset me. I am sure that you are disappointed to hear that but nonetheless it is true. Barefaced claims without support only disappoint me. I am always looking for an interesting discussion.

Let me make this clear about informal online discussions.

I can't lose an argument unless I lose my temper. This holds for all of us, you included. The worst that can happen is that someone doesn't learn anything. Which, so far, is the case with you. You have said nothing that has the support of evidence so you haven't said anything we can learn from nor did you learn anything from us but that was your own failure not ours.

Ethelred
ubavontuba
2.3 / 5 (3) Jun 27, 2010
I didn't say otherwise. I said FLOODS of the sort involved in a dam break will straighten the meanders. UNLESS they are already well entrenched.

What part of that is wrong or hard to understand?
None of it (for me). It's that the YECs can rightfully claim GC meanders could occur naturally in a severe flood.
Of course it is. So the YECs make up lies and engage in fantasy to evade it.
Obviously, but that part isn't for them.
You REALLY haven't had many discussions with YECs have you?
I usually avoid non-science (read, nonsense)
You are preaching to the choir. Despite all the evidence that has ever been produced the YECs still think EITHER the Grand Canyon was produced in the Great Flood 4,400 years ago OR Jehova made it look exactly the way it does. Apparently just to confuse the issue.
Right. Two strategies:

1.Calcite deposits take time, proving the GC wasn't one great flood.

2. Are you (the YEC's) really going to contend that God has perpetrated a lie?
ubavontuba
2.3 / 5 (3) Jun 27, 2010
@Ethelred:

I suspect your initial read of C2020 being a YEC supporter is correct (notice how he called scientific dating techniques, "philosophy."). However, at least he's trying to think it through. I think it'll be very interesting (and telling) to see how he interprets the calcite data.
Ethelred
5 / 5 (3) Jun 28, 2010
1.Calcite deposits take time, proving the GC wasn't one great flood.
If you do a search on fossilization you will find fossilized hats and teddy bears on Creationist sites. They pretend that encrustations are the same as lithification. So I don't think calcite deposits will phase them. Perhaps I am wrong on this.
2. Are you (the YEC's) really going to contend that God has perpetrated a lie?
I have seen them do it. They just don't call it a lie. They call it a test of their Faith. Apparently nearly anything disturbing can be construed as a test of faith. When asked why they believe an ancient book written by men that OTHERS claim were inspired by Jehovah versus a world THEY claim was CREATED by Jehovah they pretty much pretend that I didn't ask. Occasionally thinking ensues instead but it might take weeks to occur. I call that success.
(notice how he called scientific dating techniques, "philosophy.").
Science used to be called Natural Philosophy.

Ethelred
C2020
2 / 5 (1) Jun 28, 2010
@ ubavontuba
Thank you for the calcite deposit link. Please note that the caves all lie below the 3200 ft elevation horizon for the eastern canyon and 3900 ft elevation for the western canyon (inner gorge rim). My original proposal was that the failure stripped the top corridor (roughly equivalent to the inner gorge rim elevation) with resultant downcutting subsequent to initial failure. Your link seems to support my proposal that fault activity could have initiated a flow path leading to breach failure.

Also, the lava dam link above clearly identified the presence of lava dams (there may have been as many as 13) in western Grand Canyon with elevations ranging from to 1600 ft to 3900 ft in elevation. The lava dams are associated with volcanic cones to the north. It is likely that these lava dams impounded water for some period of time prior to failure, thus complicating the life history of your calcite deposits.

@Ethelred
Please identify how runoff reaches the Gulf of Mexico.
ubavontuba
1 / 5 (2) Jun 28, 2010
If you do a search on fossilization you will find fossilized hats and teddy bears on Creationist sites.
Thanks for the tip. That was a hoot! In this case i would ask them: So where then are all the dinosaur bones and such that AREN'T fossilized?
They pretend that encrustations are the same as lithification. So I don't think calcite deposits will phase them. Perhaps I am wrong on this.
After doing a little research, I've little doubt you're correct on this.
I have seen them do it. They just don't call it a lie. They call it a test of their Faith. Apparently nearly anything disturbing can be construed as a test of faith. When asked why they believe an ancient book written by men that OTHERS claim were inspired by Jehovah versus a world THEY claim was CREATED by Jehovah they pretty much pretend that I didn't ask. Occasionally thinking ensues instead but it might take weeks to occur. I call that success.
An excellent question, indeed.

Continued...
ubavontuba
2.3 / 5 (3) Jun 28, 2010
@Ethelred (2 of 2):

I would tend to phrase questions along the lines of: You mean God is a deceiver? Isn't that supposed to be the other guy? ...and such.

Science used to be called Natural Philosophy.
Right, but it appears to me C2020 didn't use "philosophy" in that context.
ubavontuba
2.3 / 5 (6) Jun 28, 2010
@C2020:
Thank you for the calcite deposit link.
You'r welcome.
Please note that the caves all lie below the 3200 ft elevation horizon for the eastern canyon and 3900 ft elevation for the western canyon (inner gorge rim). My original proposal was that the failure stripped the top corridor (roughly equivalent to the inner gorge rim elevation) with resultant downcutting subsequent to initial failure. Your link seems to support my proposal that fault activity could have initiated a flow path leading to breach failure.

Also, the lava dam link above clearly identified the presence of lava dams (there may have been as many as 13) in western Grand Canyon with elevations ranging from to 1600 ft to 3900 ft in elevation. The lava dams are associated with volcanic cones to the north. It is likely that these lava dams impounded water for some period of time prior to failure, thus complicating the life history of your calcite deposits.
So how old, are you saying, is the Grand Canyon?
Ethelred
4 / 5 (4) Jun 29, 2010
Please identify how runoff reaches the Gulf of Mexico.


Its a desert. It doesn't.

But it doesn't flow into the Grand Canyon either since the ground slopes to the south.

You are not going to change the landscape by wishing.

Have a link.
http://en.wikiped...yon_area

The Canyon was nearly at its present depth when those lava dams formed. Thus the dams have contributed little to the present depth of the Canyon.

Ethelred
C2020
1 / 5 (1) Jul 12, 2010
Thank you again for your patience. It took a couple of weeks to put together dam breach analyses from two different software packages for cross checking of results.

Controlling cross sections of Grand Canyon above the incised channel, although large in size, are very similar in appearance to various stream systems I have modeled over the years.

Consistent with our initial estimate, if we consider that only a small portion of the 140,000 sq.mi. Colorado River basin at Grand Canyon is inundated/impounded, we obtain a storage total of approximately 3 to 4,000 cu.mi. at an elevation of 5,600 ft. (Telegraph Flat low point between Vermillion Cliffs to the north and Buckskin Mountains to the south).

to be continued (1 of 4)
C2020
1 / 5 (1) Jul 12, 2010
Using the following reasonable controlling boundary conditions:

1. Breach width of 0.5 mi. at failure elevation of 5,600 ft.,
2. 48-hour failure time to low failure elevation of 4,000 ft.,
3. Although the mechanism of failure is unknown, consider inception of failure from tectonic activity as most likely probability given that the Colorado follows the Toroweap fault (approx. 800 ft. offset) and the Hurricane fault (approx. 1300 ft. offset) and may have been influenced by others (such as Bright Angel, etc.),
4. Use half the computed breach output discharge in the hydraulic analysis as a conservative reduced estimate for flow rate.

We obtain the following results:

1. An adjusted discharge rate of 200 million cfs (approx. 5 cu.mi. per hour) for many days,
2. Hydraulic velocities for the entire 180 mi. corridor between 15 to 50 fps for days (cavitation may occur at 12 fps),
3. Flow depths of at least 1,000 to 1,200 ft. for the entire 180 mi.

to be continued (2 of 4)
C2020
1 / 5 (1) Jul 12, 2010
These results strongly suggest that a dam breach could generate the necessary cavitation and scouring forces to excavate the Grand Canyon. Please see the following links for additional supporting details:

1. Cavitation general principles:
Cavitation in Chutes and Spillways
http://www.usbr.g...EM42.pdf
pg 5 - Glen Canyon sandstone erosion

2. Cavitation associated with concrete:
Hoover Dam - Concrete International - 40fps
http://www.usbr.g...0581.pdf

3. Cavitation in relatively low velocity settings:
http://www.iahr.o...VITATION BY MACROTURBULENT.html

4. River incision into bedrock:
http://home.coa.e...0gsa.pdf

to be continued (3 of 4)
C2020
1 / 5 (1) Jul 12, 2010
While there may be refinements to be pursued, it is a reasonable proposal, with suitable documentation and supporting calculations. The refinements may include lava dam development and failure with associated establishment of calcite deposits, etc.

Finally, the predilection for a southern flow route is not supported by the observable topographic evidence. The plateau does not slope to the south. The best we can say is that there exists an overflow ridge at Peach Springs having an elevation of approx. 4922 ft. elevation. It may be noted that the breach analysis at this location produces water surface elevations below the Peach Springs controlling overflow elevation.

The Wiki link http://en.wikiped...yon_area is not convincing, relevant nor sufficient as reference documentation to support the southern flow route position. It should be noted that the Continental Divide separates the Gulf of Mexico from the Colorado River basin (and its outlet at the Gulf of California).

(4 of 4)
Caliban
1 / 5 (1) Jul 12, 2010
I don't think you've gone nearly far enough!
Why not just assume an original surface of, say, 7500 feet above sea level? And 20K mi^3 H2O? Then your notion of overtopping or failure of impoundment would be totally irrefutible.

C2020-
You desrve some credit for going to the trouble to elaborately modify several of the key factors to fit your theory, but the bare facts on the ground just don't support your position, WITHOUT EXTENSIVE, UNDOCUMENTED MODIFICATION, that is entirely unsupported by decades of research.

Yet you "fixed" the whole problem in two short weeks, and turn all of this understanding -arrived at after a century of painstaking research- upside down. If, that is, you are responsible for any of this effort, and aren't shilling for someone else.

No one with any scientific understanding of the principles, processes, and facts of the matter at hand is going to buy this.

You can probably market your "blockbuster" new book through the Discovery Institute, though.
C2020
2 / 5 (1) Jul 13, 2010
@Caliban:
Please note that I did not propose an overtopping event in this context because I do not believe the data appear to support this possibility. Notice also that I did not choose to use 7,500 ft. nor 20K cu.mi. because the available scientific information does not appear to support those numbers either.

It is apparent from your response time that you have not adequately reviewed the scientific links provided to support my position. Please elaborate on the scientific principles, processes and facts you believe I have not obeyed (with specific details, not handwaving assertions).

Further, what key factors and bare facts am I ignoring? Please provide suitable scientific references for your position and for support of your severely inaccurate canyon volumes initially mentioned above.

If you review the documentation with detached emotions, you may see that geologic time frames for actual Grand Canyon establishment are independent of this dam breach hydraulic analysis.
C2020
2 / 5 (1) Jul 13, 2010
Erratum: I should clarify that what I mean above by "geologic time frames" is the point (or even duration of time) in geologic history at which Grand Canyon was established. No one can credibly say they know this in an exacting scientific sense.
ubavontuba
2.3 / 5 (6) Jul 13, 2010
@C2020

I didn't see an explanation for the calcite deposits. What's up with that?
C2020
1.5 / 5 (2) Jul 13, 2010
@ubavontuba:
My initial comments and related comments above suggest a possible relationship between the calcite deposit development and lava dams (given the various dam elevations).

If you recall, the authors of the link you cited declared an underlying assumption for calcite deposit development being tied to groundwater decline rates based on incision rates (i.e. "The age and evolution of the Grand Canyon have been subjects of great interest and debate since its discovery. We found ... uranium-lead dating evidence for an old western Grand Canyon on the assumption that groundwater table decline rates are equivalent to incision rates.")

My earlier point was that known lava dam development and failure very likely influenced the life history of those calcite deposits and that this is not being considered by the authors in their research.

Again, I propose that the calcite history follows subsequent to initial breach failure because it occurs below the inner gorge rim elevations.
Ethelred
3 / 5 (2) Jul 13, 2010
if we consider that only a small portion of the 140,000 sq.mi. Colorado River basin
The basin was created BY erosion INTO the river in the first place. Until you have a deep river you don't get a basin of that depth.
Although the mechanism of failure is unknown, consider inception of failure from tectonic activity
It is likely that in most cases the breach happened BEFORE the dam top was reached due the usual flaws in that natural dams have.
These results strongly suggest that a dam breach could generate the necessary cavitation and scouring forces to excavate the Grand Canyon.
Except that such forces, the ones YOU calculated, were dependent on the Canyon already being at its presents depth. So where, given YOUR numbers, did the cutting happen since it had already happened both in your own numbers and in those given by geologists.

Continued
Ethelred
3 / 5 (2) Jul 13, 2010
While there may be refinements to be pursued,
Yes like using numbers that are based on YOUR assumption that the river wasn't deep already. Which you didn't do and doesn't fit the known geology in any case since the river was already at its present depth when the dams formed.
Finally, the predilection for a southern flow route is not supported by the observable topographic evidence.
Wishful thinking.
The best we can say is that there exists an overflow ridge at Peach Springs having an elevation of approx. 4922 ft. elevation.
Both the North Rim AND the South Rim are higher than that.
The Wiki link http://en.wikiped...yon_area is not convincing,
Of course not. Reality doesn't convince YECs.
It should be noted that the Continental Divide separates the Gulf of Mexico from the Colorado River basin (and its outlet at the Gulf of California).
Yes and before there was a breach in the divide the Colorado River ended in an inland sea.

Ethelred
ubavontuba
1.8 / 5 (5) Jul 15, 2010
Again, I propose that the calcite history follows subsequent to initial breach failure because it occurs below the inner gorge rim elevations.
Sorry, that simply won't do. You're going to have to show calcite deposits at various elevations in known, quick dam burst carvings to support your arguments. For instance, regarding your Teton Dam collapse reference, were any calcite deposits left behind? How thick were they? How do they relate to the Grand Canyon calcite deposits?

How about the story that we're commenting on? are there any calcite deposits in the Canyon Lake gorge?

And most importantly, how long does it take Colorado River water to build similar calcite deposits?
Ethelred
3 / 5 (2) Jul 16, 2010
I wanna know how the breaking of a dam cut the river down thousands of feet.

Right to where the dam's base was. Before it broke and started the cutting.

In other words a dam that is ALREADY down at or near the present bottom of the river couldn't have anything to do the process of eroding down to the level of the bottom of the dam.

Ethelred
C2020
1 / 5 (1) Jul 16, 2010
Sorry, that simply won't do.


Please review comments to Ethelred (to follow). Your referenced calcite deposits (Polyak, et al.) are part of an historic geologic formation. It is not necessary to demonstrate that dam breach failures produce calcite deposits in all systems. It is only sufficient to demonstrate that calcite deposits may have formed under different circumstances than Polyak, et al. recommend and/or that formation of deposits are either independent of the initial dam breach failure or strongly influenced by the structural and hydrologic factors deliberately excluded by Polyak, et al.

I propose that the deposits are independent of the initial breach failure down to the inner gorge rim elevation, since the deposits all occur below this elevation and are uniquely tied to inner gorge establishment and groundwater elevations, whether that groundwater was influenced by erosion, aquicludes or volcanism.
C2020
1 / 5 (1) Jul 16, 2010
@Ethelred:
The basin was created BY erosion INTO the river in the first place. Until you have a deep river you don't get a basin of that depth.

It may be that, prior to Grand Canyon establishment, the area east of the Kaibab Plateau was an inland sea, much like the present Great Lakes system. The geology of the area recommends this view (note: I do not mean the mechanism of lake formation, but existence and scale of formation).
It is likely that in most cases the breach happened BEFORE the dam top was reached...

This is consistent with my proposal giving a failure water depth of 5600 ft. and probable minimum Kaibab Plateau elevation of about 7000 ft. in the breach section.
So where ... did the cutting happen...?

That is one point of the above article. When cavitation and scouring happen along a corridor from breach failure, new channels are formed that did not exist before. Water from a breach failure cuts a new channel (see also comments below).

(1 of 5)
C2020
1 / 5 (1) Jul 16, 2010
It is understood that the model is using an established hydraulic corridor. One must necessarily make estimations about the hydraulic condition of the corridor given the present topography of the canyon. The dam breach analysis simply answers the following questions:

(1) Would a breach failure produce sufficient water to fill the canyon corridor?
(2) Could that water achieve velocities necessary for cavitation and scouring along the entire corridor?
(3) Is there a likely source with sufficient volume of impounded water in order to maintain a significant portion of breach failure flow for an extended time?
(4) Is there a likely failure mechanism, given the surrounding geologic formations?

Since the analysis answers these questions in the affirmative, we conclude it is a potential solution for Grand Canyon formation. Obviously, more research is warranted to establish the hypothesis as a theory, but the rough calculations recommend further research along these lines.

(2 of 5)
C2020
1 / 5 (1) Jul 16, 2010
YOUR assumption that the river wasn't deep already...


You may have missed the extent of my proposal. I have indicated that the breach failure could have produced initial surface destruction down to the inner gorge rim elevation. End of breach water and/or later drainage events may have created the inner gorge meandering system through on-going erosion over an extended period of time.

Subsequent to final or nearly final establishment of the canyon thalweg elevation, volvanic activity to the north produced lava dams blocking the Grand Canyon inner gorge to depths sufficient to influence the groundwater table along the length of the entire canyon. It appears that as many as thirteen of these dams at various elevations were created and failed. The duration of each dam and its influence on the adjacent groundwater table is not known.

(3 of 5)
C2020
1 / 5 (1) Jul 16, 2010
Wishful thinking.

I will try to re-phrase my opposition to your proposal that the original topography would demand a southern flow route.

There appears to be nearly uniform assent that Grand Canyon was formed by water. The real debate is the mechanism(s) that produced the formation(s) there present. To say that a breach failure could not work because water flows to the south is an implicit contradiction because the very existence of Grand Canyon dictates that it did not. This is a logical truth regardless of the rate of erosion. The fact of its existence demands an original topography necessary to produce a flow path consistent with the present canyon corridor. There are no apparent relict hydrologic or hydraulic features suggesting drainage from the north rim/plateau to the Peach Springs area that would recommend your view.

If you know of any, please provide the specific relict features for review.

(4 of 5)
C2020
1 / 5 (1) Jul 16, 2010
The reason I say the Wiki link is not particulary persuasive is due to the high level of uncertainty in its dialogue. For example, consider the following quote:

"The mechanism by which the ancestral Lower Colorado River captured this drainage and the drainage from much of the rest of the Colorado Plateau is not known. Possible explanations include headward erosion or a broken natural dam of a lake or river. Whatever the cause, the Lower Colorado likely captured the landlocked Upper Colorado somewhere west of the Kaibab Uplift. The much larger drainage area and yet steeper stream gradient helped to further accelerate downcutting."

Whatever the cause? This is certainly not a definitive commitment to slow gradual erosion of the canyon. Further, it seems to recommend as a possibility the hypothetical process I have proposed in these posts.

(5 of 5)
C2020
1 / 5 (1) Jul 16, 2010
I wanna know how the breaking of a dam cut the river down thousands of feet.

I am not sure I understand exactly what you mean. If you could relate specific elevations to your comments it would help.

In any case, my proposal was that the failure occurred from 5600 ft. down to approx. 4000 ft. (bottom of dam failure and approx. elevation of inner gorge rim in this case).

The elevation of Lake Meade bottom is below 1000 ft. Water, having a significant abrasive sediment load, with velocities of 20 fps dropping from 4000 ft. to 1000 ft. would certainly be sufficient to begin the process of inner gorge downcutting and development.
ubavontuba
2.3 / 5 (3) Jul 16, 2010
@C2020:
Please review comments to Ethelred (to follow). Your referenced calcite deposits (Polyak, et al.) are part of an historic geologic formation. It is not necessary to demonstrate that dam breach failures produce calcite deposits in all systems. It is only sufficient to demonstrate that calcite deposits may have formed under different circumstances than Polyak, et al. recommend and/or that formation of deposits are either independent of the initial dam breach failure or strongly influenced by the structural and hydrologic factors deliberately excluded by Polyak, et al.
Okay then, you're going to have to prove this. How did they suppposedly form independent of Colorado River water, or lake levels? Show relevant examples of similar and known occurences.

Seriously. You can't run away from this and be credible. Calcite deposits don't just occur willy-nilly.

Continued...
ubavontuba
2.3 / 5 (6) Jul 16, 2010
I propose that the deposits are independent of the initial breach failure down to the inner gorge rim elevation, since the deposits all occur below this elevation and are uniquely tied to inner gorge establishment and groundwater elevations, whether that groundwater was influenced by erosion, aquicludes or volcanism.
Again, that simply won't do. You're going to have to show calcite deposits are a normal characteristic of your proposed conditions. You're going to have to show calcite deposits at various elevations in known, quick dam burst carvings, or experimentally (and verifiably) demonstrate how this can occur specifically to the Grand Canyon.

Otherwise, you're essentially saying they appeared there by magic. Is this your contention?

C2020
1 / 5 (1) Jul 18, 2010
How did they suppposedly form independent of Colorado River water, or lake levels?

I did not say they formed independent of the Colorado River water, I said they formed independent of the proposed initial dam breach failure flows. A more careful read of your calcite link will show that Polyak, et al. indicate that the only connection between the cave calcite deposits and the creation of the Grand Canyon is their assumption that groundwater descent rates are coeval with incision rates and thus link the cave deposits with downcutting rates on the river.

Further, Polyak, et al. also assume that the groundwater table is flat and that structural and hydrologic considerations can be neglected in their analysis of incision rates.

None of these assumptions can be proven true and my earlier point was that structural and hydrologic features may have a greater influence in calcite deposit formation than Polyak, et al. considered.

(1 of 3)
C2020
1 / 5 (1) Jul 18, 2010
Show relevant examples of similar and known occurences.

and
You're going to have to show calcite deposits are a normal characteristic of your proposed conditions.

Polyak, et al. make no representation that calcite deposits should be uniquely linked to hydraulic catastrophes, nor do they represent that groundwater and incision rates are coeval for all stream systems, nor do they represent that calcite deposits will form in every stream system regardless of incision rates. They only represent that calcite deposits may form under certain geo-chemical conditions near the groundwater table. Grand Canyon is one such location.

To propose a required link between calcite deposits and dam breach failure is inconsistent with representations made by Polyak, et al. Read the paper http://www.mmjb.i...868/1377 and tell me why you believe the two should be linked.

(2 of 3)
Ethelred
1 / 5 (1) Jul 18, 2010
The real debate is the mechanism(s) that produced the formation(s) there present
Not really. There is the usual debate over details. And the attempts to obfuscate by YECs.
say that a breach failure could not work because water flows to the south is an implicit contradiction because the very existence of Grand Canyon dictates that it did not
Sorry but breach failure was not involved what I said. Only YEC crap was involved. Breach failure can only happen AFTER the Canyon has been eroded quite deep into the plateau.
The fact of its existence demands an original topography necessary to produce a flow path consistent with the present canyon corridor
Of course, the topography had to have a river there before the plateau was formed by the land rising to its present height. But that is reality and not what a YEC engages in. Perhaps you have forgotten that what I said was directed at YECs.

Continued
Ethelred
1 / 5 (1) Jul 18, 2010
There are no apparent relict hydrologic or hydraulic features suggesting drainage from the north rim/plateau to the Peach Springs area that would recommend your view.
Nor is there any expectation of such on my part since the land arose with the river already cutting into the land. The Canyon is a result of a pre-existing river on land that used to a much lower altitudes.

This is certainly not a definitive commitment to slow gradual erosion of the canyon
That is sign of not wanting to see what you actually saw. It said:
ancestral Lower Colorado River
The LOWER COLORADO is not the Canyon. In the worlds of one my High School teachers 'Read it again' this time noticing that the lower Colorado is below the Canyon.

It is not the fault of the Wiki if the Reader simply doesn't want to accept reality.
I am not sure I understand exactly what you mean.
Sorry but I think the problem is that you don't want to.

Continued
Ethelred
1 / 5 (1) Jul 18, 2010
In any case, my proposal was that the failure occurred from 5600 ft. down to approx. 4000 ft. (bottom of dam failure and approx. elevation of inner gorge rim in this case).
Which doesn't fit the facts. The lava dams went to near the bottom of the gorge. Pretty near the present bottom. So since they started near the PRESENT bottom they could not have cut down thousands of feet to the present bottom. Much of the inner gorge MIGHT have been cut by dam breaches. But the inner gorge formed by cutting down from what was already an extensive and deep canyon. All of this took millions of years. It is possible that the much of the inner gorge was formed in the last 700,000 years but I must remind you that you started this when disagreeing about the statements that the Grand Canyon was not formed by the mythical Great Flood. Clearly even 700,000 years is just a tad too early for the flood that is in the Bible.

Continued
Ethelred
1 / 5 (1) Jul 18, 2010
It is interesting that on several YEC sites that showed up in searches about the lava dams not a single one took note of the fact that all but the very latest dam were far older than the Earth according to Fundamentalist thinking. Part of the spread their confusion philosophy I suppose. Never admit that they just proved themselves completely wrong even if their numbers were right.
would certainly be sufficient to begin the process of inner gorge downcutting and development.
Except that much of the gorge had already been cut when the dams formed
http://www.mmjb.i...868/1377
Busted link. You MUST put the link on a separate line, the link and the link ONLY, no additional things like sentence structure such as a period. This needs to be done on almost all forums. Only those that allow HTML or Pseudo-HTML code can have an in-line link.

Ethelred

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