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I was looking at the Kura river in Google Maps satellite mode and I saw these U-shaped bodies of water:

U-Shaped

There are other U-shaped bodies of water too:

40.615881° N, 47.205031° E

40.101139° N, 47.963825° E

And so many others.

Why are these U-shaped bodies of water frequent in the region?

Snack Exchange
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1 Answers1

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They look like oxbow lakes. Some meander scars (crescent-shaped, but dry) are also visible. Here is an excerpt of the "OXBOW" entry in Encyclopedia of Geomorphology (2013):

An abandoned meander (see MEANDERING) loop along an alluvial river. It is the most common type of lake of fluvial origin. As a logical consequence of the lateral shifting and the general downstream migration of meanders, it develops from the interplay of channel erosion and accumulation separated in space. Oxbows are produced by meander cutoffs [...] The American name emphasizes the crescent shape, while in many other languages an oxbow is called a ‘dead arm’ (e.g. in French: bras mort). [...] Meander scars are oxbows completely filled up with mineral and organic matter. They remain discernible in the landscape for a long time. Classic examples are found along several major rivers of the world, including the Mississippi, the Amazon and the large rivers of Siberia.

Jean-Marie Prival
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    Thank you. Sounds you're right. I also looked at Mississippi river and saw some of the same lakes there. But I think Kura river has more of them. – Snack Exchange Oct 12 '23 at 15:07
  • @SnackExchange meandering river have lots and lots of them the sediment around them is layer upon layer of them. Search oxbow lake and meandering river together. – John Oct 12 '23 at 22:02
  • In southern Texas, oxbow lakes formed from meanders of the Rio Grande are called "resacas." – barbecue Oct 12 '23 at 22:36
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    @SnackExchange A lot also depends on how heavily altered a landscape is by humans. I'm not sure about the USA, but in Western Europe, all major rivers have been heavily altered by humans who wanted shorter shipping routes and use the land near the river. – gerrit Oct 13 '23 at 06:58
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    In Australia, it's called a billabong, I believe from an Aboriginal word. They're mostly stagnant except during the rainy season. – Cristobol Polychronopolis Oct 13 '23 at 16:12
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    @CristobolPolychronopolis All this time I thought a billabong was just a place for a swagman to spring into. – Wayne Conrad Oct 13 '23 at 18:30
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    As long as he starts out camped beside it, waiting for his billy to boil. (Under a coolibah tree.) – Cristobol Polychronopolis Oct 13 '23 at 18:36
  • A big one near the Mississippi River in Louisiana is called False River. – RonJohn Oct 15 '23 at 00:44
  • Yes, oxbow lakes. You could note that the Kura river has been artificially straightened in many locations, leaving behind more oxbow lakes than might be present naturally. – James K Oct 15 '23 at 18:50