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Rapid canyon formation and fossils

This week’s feedbacks are both answered by geologist Dr Emil Silvestru, CMI-Canada. First, Andrew R. from New Zealand writes:

I am having trouble understanding how such features as sharp curves in canyons, such as “Horseshoe Canyon", formed rapidly. Searches for this topic lead to, “slow, gradual, meandering" etcetera as an explanation. Please, I trust there must be an alternative “Biblical age" explanation and am hoping you can provide me with it.
Photo by Christian Mehlführer, commons.wikimedia.org Horseshoe canyon

Dr. Silvestru replies:

Dear Andrew,

Thank you for this quite interesting inquiry. The subject of meandering is a much more complicated one than generally acknowledged in the geology literature. The vast majority of textbooks and treatises leave out meandering in hard rocks, especially meandering in caves. River meandering is a fairly straightforward process and it is almost certainly and exclusively caused by flow dynamics and sediment transportation. This meandering is practically 2-dimensional.1 In caves, 3-dimensional meandering is much more ample, the vertical component being sometimes on par with the horizontal one.

With the above in mind, slow meandering over long ages in hard rocks becomes quite a problem. In order to avoid the difficulties, they almost always avoid discussing vertical meandering, which is not easily explainable by slow dissolution—chemical and mechanical erosion also don’t explain it.

If you can, please check this image out: http://www.newswise.com/articles/drainage-of-subglacial-lakes-created-canyons-of-antarctica-12-14-million-years-ago (you can enlarge it quite a lot) you will notice that confined flow (between the bottom of the ice sheet and the bedrock) can create significant meandering in very hard rocks during catastrophic events. If you have a look at this video: http://www.youtube.com/watch?v=8LQIuuDSDJE you can see how wonderful and elegant sharp bends were carved in hard rock by glacial meltwater on Kelley’s Island in Ohio, US. Catastrophic drainage again—the subglacial flow created the grooves. Splendid examples of meandering in hard rocks are also found in the Channeled Scablands in Washington State which were the result of at least one catastrophic glacial meltwater release from Lake Missoula.

To my knowledge, meandering hard rock riverbeds are explained as the result of encased flow in soft sediments covering the hard rocks and subsequent entrenchment in the subjacent hard rock. This is a type of two-dimensionally confined flow. But it does not explain three-dimensional meandering carved by muddy sediment flows and water streams both free-flowing and trapped beneath sediments.2 In caves vertical meandering is almost certainly caused by a combination of rock mineral inhomogeneity, sedimentary structure and tectonics within an obviously confined flow regime.

So with all this in mind, here is what I personally believe about the issue of meandering in a Young-Earth, diluvial scenario:

Lab experiments have shown that pellicular (thin layer) drainage on soft surfaces always causes branching patterns, not meandering. You can clearly see this at low tide on sandy shores. The retreating waters of the Flood on the other hand, were in places kilometers deep and it is quite possible that at the bedrock-water interface turbulence (caused by the friction with the sediment) created meandering patterns – a special case of confined flow. Riverbed meandering in hard rock is only present in horizontally-layered rocks, which are in turn the result of massive, water-borne sediment flows.

I hope this sheds a bit of light on the issue. If you have more questions or need more information, please do not hesitate to write.

Sincerely in Christ
Emil Silvestru


Next, Paul J. from Australia asks:

Hello to everyone at Creation Ministries,

Keep up the good work! I have recently been sent this series of questions pertaining to the fossil record and how come it looks like it points to evolution regarding geological and fossil layers. It was sent to me by a friend who is an ardent evolutionist and I was hoping you could help me with some answers or references to answers to provide him with.

Many thanks,
Paul

How was the fossil record sorted in an order convenient for evolution? Ecological zonation, hydrodynamic sorting, and differential escape fail to explain:

* the extremely good sorting observed. Why didn’t at least one dinosaur make it to the high ground with the elephants?
* the relative positions of plants and other non-motile life. (Yun, 1989, describes beautifully preserved algae from Late Precambrian sediments. Why don’t any modern-looking plants appear that low in the geological column?)
* why some groups of organisms, such as mollusks, are found in many geologic strata.
* why organisms (such as brachiopods) which are very similar hydrodynamically (all nearly the same size, shape, and weight) are still perfectly sorted.
* why extinct animals which lived in the same niches as present animals didn’t survive as well. Why did no pterodons make it to high ground?
* how coral reefs hundreds of feet thick and miles long were preserved intact with other fossils below them.
* why small organisms dominate the lower strata, whereas fluid mechanics says they would sink slower and thus end up in upper strata.
* why artifacts such as footprints and burrows are also sorted. [Crimes & Droser, 1992]
* why no human artifacts are found except in the very uppermost strata. If, at the time of the Flood, the earth was overpopulated by people with technology for shipbuilding, why were none of their tools or buildings mixed with trilobite or dinosaur fossils?
* why different parts of the same organisms are sorted together. Pollen and spores are found in association with the trunks, leaves, branches, and roots produced by the same plants [Stewart, 1983].
* why ecological information is consistent within but not between layers. Fossil pollen is one of the more important indicators of different levels of strata. Each plant has different and distinct pollen, and, by telling which plants produced the fossil pollen, it is easy to see what the climate was like in different strata. Was the pollen hydraulically sorted by the flood water so that the climatic evidence is different for each layer?

Dr. Silvestru replies:

Hi Paul,

Thanks for the copious set of questions. I rush to answer them the way they’ve been asked: short and without many references. Please find the answers inserted in your text. Please do not hesitate to write if you need more details.

Best regards

Emil Silvestru

How was the fossil record sorted in an order convenient for evolution? Ecological zonation, hydrodynamic sorting, and differential escape fail to explain:
* the extremely good sorting observed. Why didn’t at least one dinosaur make it to the high ground with the elephants?

Dinosaurs have been found in layers above their evolutionary extinction age (k/t boundary) but have always been described as “reworked”. It is also quite obvious that dinosaurs and elephants did not share the same habitat.

* the relative positions of plants and other non-motile life. (Yun, 1989, describes beautifully preserved algae from Late Precambrian sediments. Why don’t any modern-looking plants appear that low in the geological column?)

Stainforth (Nature, 1966) described pollen in the Roraima Formation (1.8 billion evolutionary years old). Angiosperms are believed to have evolved only in the Cretaceous (Archefructus sinensis)

* why some groups of organisms, such as mollusks, are found in many geologic strata.

Why are mollusks present today in so many different habitats from terrestrial to deep ocean?

* why organisms (such as brachiopods) which are very similar hydrodynamically (all nearly the same size, shape, and weight) are still perfectly sorted.

In sedimentology ‘sorting’ means deposited by size. I suspect this question means “why are brachiopods only at certain levels in the fossil record?” This is because of habitat again as well as their having a short ‘foot’ which made them less mobile when in fast currents.

* why extinct animals which lived in the same niches as present animals didn’t survive as well. Why did no pterodons make it to high ground?

The same is a valid question for the evolutionary mystery of why crocodiles survived the great K/T extinction while dinosaurs did not.

* how coral reefs hundreds of feet thick and miles long were preserved intact with other fossils below them.

Wrong wording. No coral reef has ever been “preserved intact”. That is a classical uniformitarian inference. When pieces of bioherms have been found inside masses of carbonate they were assumed to reflect a reef. In fact, modern reefs are never incorporated in carbonate platforms (the vast majority of limestone deposits in the rock record are areal platforms [those covering a large area rather than a localized deposition] and even larger surfaces). When preserved as narrow limestone ridges with broken elements of reef, limestone massifs are almost always olistoliths3 revealing tectonic displacement. They frequently rest on ophiolites,4 not fossil beds.

* why small organisms dominate the lower strata, whereas fluid mechanics says they would sink slower and thus end up in upper strata.

Slow sinking means certain ‘non-fossilization’ i.e. bloating and floating and decomposition. Fossilization requires rapid burial, special pH conditions and rapid lithification. All perfectly compatible with a global flood.

* why artifacts such as footprints and burrows are also sorted. [Crimes & Droser, 1992]

Wrong use of ‘sorting’ again. How can one ‘sort’ footprints? Sorting is a sedimentological term. I assume the question refers again to certain position in the fossil/rock record. Footprints are also not artifacts, but ichnites. Anyway, why are the earliest dinosaur footprints 20 million (evolutionary) years older than the earliest dinosaur fossils? If the person who asked the question above answers this, he will also find the answer to his/her question.

* why no human artifacts are found except in the very uppermost strata. If, at the time of the Flood, the earth was overpopulated by people with technology for shipbuilding, why were none of their tools or buildings mixed with trilobite or dinosaur fossils?

Overpopulation? Where did the questioner read that? According to some scientists, even today we are not truly overpopulating the planet. As for humans being preserved in the upper layers only, humans would have seen the rising waters, known what was happening, and been able to take temporary refuge on high ground. Some would have been able to take to buoyant objects, perhaps hastily constructed rafts (or even boats built pre-Flood). But most would have drowned in the later stages of the Flood, and not buried by sediment. So consequently they did not fossilize. See also Chapter 15 from the Creation Answers Book, Where are all the human fossils? Consider this question, too: Why do we not find human and coelacanth fossils together? If that is taken to mean that they never lived on the earth at the same time, then that deduction is clearly in error, since humans and coelacanths are known to both live on the earth today.

* why different parts of the same organisms are sorted together. Pollen and spores are found in association with the trunks, leaves, branches, and roots produced by the same plants [Stewart, 1983].

Incorrect. Pollen was found in the Roraima formation (see above) without any other plant remains. Palynology as a branch of paleobotanics only studies pollen in rocks and very often without any other plant remains available.

* why ecological information is consistent within but not between layers. Fossil pollen is one of the more important indicators of different levels of strata. Each plant has different and distinct pollen, and, by telling which plants produced the fossil pollen, it is easy to see what the climate was like in different strata. Was the pollen hydraulically sorted by the flood water so that the climatic evidence is different for each layer?

Pollen-based climate reconstructions are viable only for the Quaternary. We have no idea how the pollen of extinct plants can reflect climate. Other data (usually oxygen isotopes) is used for that. Previous to the Flood, there was a vast array of plants and pollen, and the climate was mild worldwide. Fossil pollen actually reflects that. Only in the Quaternary, because of the Ice Age, do we have drastic flora shifts recorded by pollen. Well, the Quaternary is post-Flood. I recommend the questioner reads science journals rather than textbooks which tend to “rosify” scientific facts, often telling stories not facts.

Sincerely,

Emil Silvestru

References

  1. Vertical meandering occurs at a very long wavelength that never exceeds 1% of the amplitude of the horizontal meandering. Return to text.
  2. While surface vertical meandering is minor compared to the horizontal, because there is three-dimensional meandering in caves, different mechanisms are in play. Return to text.
  3. Very large chunks of rock resting on younger rocks. For instance, a piece of broken coral reef which slid down a continental slope which rested on and was buried by younger sediments. Return to text.
  4. Basalts emplaced along mid-ocean ridges. Return to text.
  5. Published: 19 February 2011