Slot Canyons Rate Surprises Geologists

Many people love to go Canyoneering  with its challenge of hiking through some of the most amazing patterns of reflected light that captives  photographers all over the world. Each year hikers observe a change in-depth, which is caused by reoccurring flash floods. In the evolutionary time frame it is assumed to take eons of time for them to be formed.

It peaked much interest in a team of geologists who wanted to find out how about long it would take. They tested for erosion rates by observing an actual incipient canyon starting during floods in the Henry Mountains, Utah. Going by “a well-constrained initial geometry of a steep, unchannelized bedrock slope” and discovered a remarkable amount of cutting – half a meter – in just 23 days of flooding from seasonal snowmelt.  If this was the actual rate, it would take only 200 years to cut 100 meters.

This was surprising for geologists who were submitting themselves to the evolutionary time frame. If the slot canyons are millions of years old then why do we still see sandstone left after all that time? The authors recognize the issue…

“Rates of fluvial bedrock incision mimic rates of external landscape forcing (e.g., tectonic uplift and eustacy [sic]) when averaged over geological time scales, but local rates of channel downcutting into bedrock can be fast during the individual floods that actually drive bedrock incision: we measured up to 1/2 m of local vertical incision into bedrock over 23 days of snowmelt runoff (Fig.9).  Local channel morphology and high but not overwhelming rates of sediment transport enabled such a high local erosion rate.”

“The local thalweg2 slope was high (~20%, Fig. 8), and the cross-sectional morphology of an inner channel focused flow and sediment transport over a narrow zone where almost all erosion occurred.  While poorly constrained, field measurements demonstrated high rates of coarse-sediment transport.”

“Additionally, preexisting inner-channel alluvium was entrained during this snowmelt runoff event, and so alluvial cover was not consistently present to mantle the inner-channel bed and inhibit bedrock erosion.  Field observations also suggest that thresholds of detachment for abrading the local sandstone are negligible (Fig. 6).”

Now let’s take cosmogenic radionuclide dating for the sake of argument with the slowest rate mentioned in the paper which would make the Navajo sandstone about 190 million years old. Using calculation from the slowest rate which is (0.4mm/year), divide by 4 to get a tenth of a millimeter per year. This would make the canyon 19 km deep which is well over fifteen times (95,000 kilometers deep) compared to the actual depth of the Grand Canyon!

By contrast, let’s take the most conservative value measured at 10mm in a year, then you could get a decently deep canyon 50 meters deep (similar to many observed) in just 5,000 years! Using the Biblical time frame keeps the slot canyons rate within reason of what is being observed!

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6 thoughts on “Slot Canyons Rate Surprises Geologists

  1. Michael,

    You say “Each year hikers observe a change in-depth, which is caused by reoccurring flash floods. In the evolutionary time frame it is assumed to take eons of time for them to be formed.” — Uh, Michael, this is not necessarily true. A depth can be changed rapidly….but that depends on how hard of soft the ground it. . . To illustrate, a sand bed would be carved into much faster than a bottom made of granite.

    And Michael, no one has ever said canyons cannot be formed in short periods of time…I have pointed this out to you many times..But you either have ignored me conveniently, or have not bothered to read what I told you.

    You then say “This would make the canyon 19 km deep which is well over fifteen times (95,000 kilometers deep) compared to the actual depth of the Grand Canyon!” — Nice, and your point is? Nobody says that canyons cannot form in short periods of time. But geologists can distinguish between canyons formed in short periods verses those formed in long periods of time. The grand canyon IS KNOWN to have been formed in a long period of time (6 million years) because if the U-shapes it has left cut through the ground. I guarantee you that this other canyon does not meet that particular criterea…at the points that have been eroded rapidly.

  2. Oh dear, now you are mixing up biology and geology …

    Biology does not predict anything about the time-scales involved in canyon formation (your ‘evolutionary time frame’). And as Kris already stated: why should ALL canyons form slowly in any model ?

    Now if you would come up with a canyon that is 5 billion years old – THAT would be interesting !

    Even a canyon that would have formed just yesterday, say between breakfast and lunch, would not mean anything for ALL canyons in the world.

  3. Quoth Michael—

    —————-

    Now let’s take cosmogenic radionuclide dating for the sake of argument with the slowest rate mentioned in the paper which would make the Navajo sandstone about 190 million years old. Using calculation from the slowest rate which is (0.4mm/year), divide by 4 to get a tenth of a millimeter per year. This would make the canyon 19 km deep which is well over fifteen times (95,000 kilometers deep) compared to the actual depth of the Grand Canyon!

    By contrast, let’s take the most conservative value measured at 10mm in a year, then you could get a decently deep canyon 50 meters deep (similar to many observed) in just 5,000 years! Using the Biblical time frame keeps the slot canyons rate within reason of what is being observed!

    ————-

    Once again, Michael proves that figures can lie, and liars can figure!

    ======

    BTW, I caught your pun about peaks and valleys: “It peaked much interest in a team of geologists who wanted to find out how about long [ther valleys] would take. ”

    Valleys peak your interest. Ho ho. ..uh… You didn’t mean “pique” did you? Forget it,. The pun was from ignorance, and not from design.

  4. Upson Downes avers that Michael does know the word “pique,” but only as a part of the compound “pique-nique.” And he knows only the American spelling, “picnic.”

  5. I’m guessing Michael thinks he has found evidence for Young Earth geology is because he doesn’t understand the concepts of conventional geology.. Oh well, Young Earthers tend to not understand it.

    YECs tend to look at the famous saying “The present is the key to the past.” From that, they then assume that this means that the rates ARE ALWAYS static. That, however, is not what it means at all… What it does mean (for example) is that if there is a landslide happening which deposites a layer of mud in an area where it wasn’t previously now in the present day, that that also means that landslides with similar results have also occured in the past as well; If we see a flood happen today which leaves a layer of sediment in a region, we know that happened in the past as well; and if we see a volcanic eruption wipe out a certain landscape and deposite a huge layer of ash, then we know the same thing has happened in the past. This is not a concept that is hard to understand.

    Michael, understand this!! The principal of uniformity (often called “uniformitarianism,” and also falsley called “evolutionary geology” by Young Earth Creationists) is misunderstood by Young Earth Creationists. It DOES NOT MEAN that every thing from erosion to the deposition of strata has to happen all at the same rate. And it certainly does not mean that erosion cannot excelerate! It only has that meaning to organizations like Answers in Genesis, the Institute for Creation Research, and Creation Ministries International, all organizations that have no understanding of geology.

    I have already pointed out in my last comment how geologists distinguish between canyons made within short periods from those from made in long periods, so I will nor regurgitate myself here.

  6. ———————————
    They tested for erosion rates by observing an actual incipient canyon starting during floods in the Henry Mountains, Utah…,.

    Using calculation from the slowest rate which is (0.4mm/year), divide by 4 to get a tenth of a millimeter per year. This would make the canyon 19 km deep which is well over fifteen times (95,000 kilometers deep) compared to the actual depth of the Grand Canyon!

    ———————————

    Too bad all of Michael’s calculations are in vain.

    Because we know exactly when the channel in the Henry Mountains that the paper refers to refers to was formed. It is not a natural channel, but was dug during the late 1970s to process uranium from a nearby mine. That’s why it made such a good subject for the study.

    This illustrates the depth of creat5uionist research. That is, none at all.

    Ah well. The best laid calculations of creationists and men gang aft agley, / An’ lea’e us nought but grief an’ pain / For promis’d joy.

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