When were ‘mismatched’ river courses carved?

During Noah’s Flood or the post-Flood Ice Age



Today’s feedback comes from Elliot in the United States who asks when river courses were carved, namely, whether it was by the retreating waters of Noah’s Flood or during the post-Flood Ice Age.

I was exploring the Upper Mississippi River region and noted a lot of mismatched river-created terrain features. For example: the Chippewa and Wisconsin rivers show what appear to be multiple erosion patterns to several different depths. There are small streams which create valleys far wider than they should be like the Turkey, Platte, and Zumbro rivers. There are river mouths that have moved around like the Rock River, which appears to have had some sort of mouths at Fulton, west of Erie, North of East Moline, and the current mouth south of Rock Island. There are huge ancient bends inscribed in the rock, most notably at Muscatine and Fort Madison. These features are all enormously larger than even the current floods on these rivers. Were these features carved by retreating flood waters being shunted off? Or were they carved by glacial melt water from a post-flood ice age? Is there any evidence in either direction.

CMI (Australia) earth scientist Dr Ron Neller responded:

Dear Elliot.

Thank you for your email. Many of us have also been fascinated by what you refer to as a ‘mismatch’, the apparent discrepancies between what we see and what we are advised or taught. Indeed, this discrepancy affected me even in my undergraduate degree days, long before I accepted young earth creation. So much so that I opened my honours thesis in 1976 with the quote:

“Nature seems to operate always according to an original general plan, from which she departs with regret and whose traces we come across everywhere.” Vicq D’Azyr (1784)

Although the quote was written by a French physician and anatomist who specialised in comparative anatomy, I felt it was similar to the comparative landscape studies that I was researching.

Regarding your reference to ‘small streams that create valleys wider than they should be’, these have been termed ‘underfit’ rivers, and much research was undertaken on various aspects of this feature (Dury, 1964).1 The South Platte River that you referred to has been written up in the academic literature as an underfit river. Underfit rivers are not just found in the USA—they are found worldwide.

An underfit river is defined as being ‘much smaller than expected from the size of its valley’ (Goudie, 2014).2 The Natural Resources Conservation Service USDA elaborated on this and defined an underfit river as a river that appears to be too small to ‘have eroded the valley in which it flows; a stream whose volume is greatly reduced or whose meanders show a pronounced shrinkage in radius’. Recognising that underfit rivers are global features, Dury (1964) sought a common explanation, and argued it to be predominantly the result of a rapid decline in stream discharge (flow rates) because of paleoclimatic changes.


Figure 1. Approximate extent of the ice sheets at the peak of the Ice Age.

As underfit rivers are worldwide, regardless of terrain and climatic settings, Dury’s argument is weak. Likewise, melt waters from the post-Flood Ice Age are not adequate, as the post-Flood Ice Age was not global (the extent of the ice age is shown in figure 1).

A good in-depth book on landform changes associated with the post-Flood Ice Age is The Missoula Flood Controversy and The Genesis Flood. This book reveals how such a catastrophic post-Flood associated with the Ice Age can alter landscapes significantly. Nonetheless, this does not provide an explanation for underfit rivers worldwide.

A better explanation would be that these the underfit rivers (i.e. the ‘overfit valleys’ they flow in) formed during the receding stage of Noah’s Flood. You will find interesting the section that deals with underfit systems in Steve Austin’s Impact article “Did Landscapes Evolve?”3 In another article I recommend, The Three Sisters: strong evidence for Noah’s Flood in Australia, Tas Walker says:

‘ … escarpments and large valleys eroded later in the Flood when the volume of water decreased and the flow was restricted to large channels. The rivers and waterfalls that now occupy valleys are minuscule compared with the volume of waters that carved the landscape during the Flood. Underfit rivers are the norm around the world, but we would expect conformable-fit rivers if millions of years were available to reach an equilibrium position.’.

I underlined an important point in Tas Walker’s argument – and that is, why has equilibrium not been achieved with lengthy periods of time available for adjustment in river systems?

You list a host of other features, such as fluctuating river mouths and cliff faces in meander bends that exceed present flood levels. The specific features that you cite I have not seen and cannot provide an answer on their formation. Hence, I refer to other outputs from Creation Ministries International that describes similar features.

How landscapes reveal Noah’s Flood: Visualizing the receding floodwaters is a good article that deals with cliff faces, whether they be gorges or waterfalls.

I think you would enjoy the podcast Can certain geological structures be explained by a global Flood? on the broader landscape topic. This one does deal with interpreting apparent ‘glacial’ features that you refer to.

Yet another article, Geomorphology provides evidence for the global flood, will give you an overall perception of the evidence of the global Flood.

I trust that these readings will highlight that what we perceive as a mismatch between what we observe and what we are taught, essentially arises out of the rejection of a Noah’s Flood, an event that Jesus himself referred to (Matthew 24:38-39).

All the best,
Dr Ron Neller
Scientist, Writer, Speaker
Creation Ministries International (Australia)

Published: 27 July 2023

References and notes

  1. Dury, G.H., Principles of Underfit Streams, U.S. Geol. Surv. Prof. Paper, 452–A., 1964. Return to text.
  2. Goudie, A., Alphabetical Glossary of Geomorphology Version 1.0, International Association of Geomorphologists, 2014. Return to text.
  3. Austin, S., Did Landscapes Evolve? ICR Acts & Facts Impact, April 1983; icr.org/article/did-landscapes-evolve Return to text.

Helpful Resources

How Noah's Flood Shaped Our Earth
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Evolution's Achilles' Heels
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Life in the Great Ice Age
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Biblical Geology 101
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