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"from about the size of an American football field to about 12 kms across" That is peak chaotic energy right there, half the sentence in metric, the other half in American, that way everyone is confused!

Wow, you guys are covering the bay lakes! My grandparents live on Lake Waccamaw, the biggest of the bay lakes in North Carolina which has unique chemistry thanks to a limestone bluff that keeps the water basic and promotes animal and plant diversity (~40 fish species compared to maybe half a dozen in the more acidic typical bay lakes), some unique to the lake. One of the acidic bay lakes Lake Phelps has old Native American canoes and artifacts dating back to 11,000 years ago and younger preserved at its bottom, and scientists put the canoes back because they couldn't preserve the canoes as well as the lake did. And a really intact whale skull from the Pleistocene dated to around 3 million years old was dug up from the bottom of Lake Waccamaw as well.

It's not every day that SciShow introduces me to a whole new phenomenon which I've never heard about before. Especially about a feature so widely distributed where I live. Long series of wiki rabbit holes sure to follow.

Very interesting thank you. I especially appreciate you saying "this hypothesis." when referring to the schools of thought on the formation of Carolina bays. So many are quick to state things like this as fact.

If you want a really interesting and well supported explanation of what the bays are, check out the catastrophe and cartography video on carolina bays by Peter Zelinka, or the videos made by Antonio Zamora.

Floridian here! I have 3 little tiny lakes like this in my neighborhood! Well, at least there *were* 3, soon to be only 1… They keep getting drained, and built over and it’s really depressing. About a mile from my home used to be this really big lot where hundreds of birds used to hang out. And now it’s a stupid bank…. Recently there has been construction on this huge plot of land nearby , like maybe 30 meters away, that was just wilderness, and for the first few weeks there were groups of vultures hanging out on what used to be their home. They don’t know why this is happening or where to go… In my yard now are bunnies, opossums, birds, storks, etc. and although I love seeing all this wildlife, it’s so upsetting that greedy humans are constantly destroying what precious little that’s left…..

The thought that it was once cold here in eastern Carolina is funny, it feels like a tropical island out here

Home to Venus Fly traps here in SC. These areas are neat to explore and some of the most beautiful places to camp.

Another hypothesis is a large meteorite struck the ice somewhere in the great lakes during last ice age and sent thousands of pieces of ice really fast and crash landed forming the pockmarks. One of the explanations is all the ovals point in the same direction.

Scientists tried to account for every single one of the Carolina bays, but they quickly find themselves… … swamped.

It's amazing that scientists can figure out what created the holes. It's also great that SciShow can tell us the... hole story.

Me, an Alaskan: those look like freeze thaw lansca- oh. Well there you go.

The thing about quartz tripped me out. I appreciate you talking about Carolina bays, it's a hard concept to wrap your mind around it attracts alot of crazy.

Carolina resident here with no clue ‘til now that these were even a thing! Thanks as always for great content!!

1:20 Writers got some directions wrong, the elliptical trends would be NW/SE and the sand concentrations appear to be W and S based on the circled portions. Later when talking about winds, NW is used and is correct.

That's neat and all, but as a South Jersey Piney, I can tell you you're wrong.. at least about the South Jersey ones. Everyone knows that the were made by the Jersey Devil to fly down and chill out at on spooky nights. Duh. (Just kidding. But the Jersey Devil lore and his blue hole in the Pinelands is a good one)

1:02 1 US football field to 12 km across. I really love that specific range of measurement.

The idea that the wind created these is astounding. The wind, in my experience changes direction continuously.

omg iv lived around these things all my life hell. I live right on the edge of one, and have always wondered what they are, I never found anyone who can give a solid answer on them, this makes so much sense

I figured it had to do with the Ice Age but it's incredible to have a much better idea of the precise mechanics that actually formed these things.

Recently saw another video on this topic. I think it made a more compelling argument for an ice age impact event. The hypothesis was an impact around the midwest/great lakes, while they were buried under a couple miles of glacier, ejected huge amounts of ice debris which created the bays when they returned to the surface. Then the bays were basically craters mad from ice impacts, which explains the elongated shape and shallowness. The main evidence was tracing the diameters of hundreds of the bays and they all appeared to converge on the hypothetical midwest impact site. In addition, there is a smaller set of bay-type land forms in Kasas or Nebraska or something which ALSO converge on that same hypothetical impact site. If the thermokarst hypothesis were correct, they'd need to explain the great plains bays which it seems would require a dominant NE to SW wind which I have a hard time believing.

I've traipsed through them and the poquosons ( another oddity in NC and VA)for quite a few decades and this makes the most sense. Falling objects ALWAYS make circular craters despite speed and angle of attack. Some of the meanest and orneryist plants bugs and critters thrive in and and around them.

What kind of demon decided to use an American football field AND kilometers as a size reference

Huh, think this is the first time I've got here this early. Time to see about these swamps.

Dont forget the Nebraska rainwater basins. Same shape, different orientation.

How great to learn something new for my 70'th birthday.

I grew up in Eastern NC and probably one of the more famous of these formations is White Lake. It was called White Lake because all the white sand. It was a big regional vacation spot with the white sand beaches and there was an amusement park of sorts, with skee ball and a boardwalk. It was traditionally sort of a low key vacation home area, it was big enough and always calm so the water skiing was great. It was large enough where you could just sort of see the other side. Today I think it's even more developed. Growing up we heard the meteor story mostly, but interesting to see that the science has continued to progress on that.

I would love to see an episode about the bubbling tides in the bay of fundy, I visited them and was told they have an ‘unknown’ cause, and this was one of the few places this phenomenon was seen worldwide.

I first discovered similar features in the arctic on google earth, as well. See the northern coast of Alaska and eastern Russia. The landscape looks almost alien and the lakes are all oriented in similar directions. I believe the current theory is that they form due to water pooling, freezing and thawing creating the lakes. I suppose the uniform orientation is due to wind direction preferentially freezing the water in one axis over others.

Saw the thumbnail and instantly knew what this was, very glad to see it being discussed. - SC resident

I have been watching the channel for a while now and in a previous episode your team talked about how when you get an organ transplant you need to take medication to prevent your body from rejecting the organ. As I recall that was because the organ has different DNA than the rest of your body. I am an identical twin and I am curious if I got a Organ from my brother would I need to take those same medications? Well anyways thank you for a great show as always.

"They also have an elliptical shape that generally points from the northeast to the southeast."? The major axis has a 90° deflection? Hank got his directions mixed up. The subtitles get it right: northwest to southeast. They also fix the other error; the sand is on the south and WEST sides.

Giant meteorites hitting the Earth are referred to as Michael Bays, not Carolina Bays.

I live in nc and see these everyday, I did not know that this was a phenomenon. How fascinating!!!

Quartz dating is a new one for me! So neat!

Great presentation! Who says that you can't teach an old dog new tricks? Also, thank you for adding captions for your deaf and hard of hearing viewers!

One was recently detected in East Texas.

As someone from the Carolinas, I never knew that this was a thing

Finally SciShow discusses Carolina bays!

You totally missed what I believe is the most likely explanation, which is a comet impacting the ice sheets of southern Canada around 13000 yrs ago. Ejecta from this impact would come in the form of icebergs hurled miles into the sky. As ice falling from great height doesn't make craters in rock, the bays are only formed in soft soils. This explains the shape of the bays, and the built up sand lips on one side. One thing the geological explanation fails to address is that the bays are mainly oriented toward a common point, with the sandy lips being opposite that direction, and prevailing winds do not align with the bay orientation. After impact, ice chunks would melt away, leaving behind a shallow oval pond. I encourage you to revisit this fascinating topic and learn about the impact theory in greater detail

I'm from Eastern North Carolina and very familiar with Carolina Bays. I noticed that similar features are visible in the far northern regions of Russia and apparently Alaska as I just learned. I always assumed they were formed by meteorites but the prevailing theory makes sense as the land is very sandy. In fact the area where I was born is known as the Sand Hills region beginning at the base of the Piedmont Fall Zone, which is also a very interesting area geologically.

“Rivers, we know rivers” Aww, how sweet 🥰

Them starting at NJ also makes a lot of sense with this theory, since New England was essentially wiped clean by a glacier that swept through the region after the last ice age, so any marks from freezing and refreezing would have disappeared

Question for you guys: How much water would it take to raise the entire ocean by 1 Planck length? There's a saying "one raindrop raises the sea" and it got me thinking... By how much?

Right away I thought of the millions of polka dot lake that cover the great northern permafrost expanse of Canada. I enjoy perusing Google Earth. Sounds like they could be the same type of feature!

I feel like I'm back in Applied Geomorphology class this is insane🙆🏽‍♀️😁😁

Could they not have the same creation story as the Kettle Lakes? It is mentioned in the video that it was during the last ice age, so it doesn't seem farfetched to me. It's possible the glaciers were breaking up there and instead of melting directly in one year, it got surrounded by dirt from the glaciers, leaving lakes behind when it finally melted. The oval shapes are then caused by the motion of the meltwater, explaining the similar directions of the oval shapes. Myron Cook has a great explanation of the creation of the Kettle Lakes, it sounds like it could apply here, but I'm no expert.

Didn't mention the ones in Nebraska and other pats of the west that point in a different orientation. Which, judging by the orientation of each bay, suggests they are caused by debris splash of ice and what not from an impact with a glacier in Michigan. Just another possibility to consider.

1:28 doesn’t he mean “Northwest to Southeast”

To those suggesting that the Bays are kettle holes left when continental ice sheets were melting: Pleistocene continental glaciation occurred only far to the NORTH of (most of) the Bay areas, covering New England, most of NY, and parts of NJ, PA and the Upper Midwest states. Kettle holes formed north of the glacial terminus, as the continental ice sheets receded toward Canada. For example, Minneapolis-Saint Paul MN area is riddled with kettle lakes. The thermokarst processes that presently occur in the near-arctic regions are different. But at the glacial maxima, the coastal plain regions of the Mid-Atlantic region had a much colder climate than today. Think: Boreal forest and Taiga. I've also read speculation (among the Younger Dryas impact proponents) that the hypothesized extraterrestrial impact "pushed down" the rock strata that form the Michigan Basin (the "bulls-eye). In Fact: In the sequence of successive sedimentary rock units that fill the Basin (ranging from early Paleozoic to Mesozoic age), each sedimentary formation THICKENS toward the center of the Basin. This indicates that the underlying crystalline basement (the deeper crust) was subsiding, more or less continuously, while each sedimentary unit was being deposited. Finally - given the limited mechanical strength of even glacial ice - it seems implausible (on a large physical scale) that a point impact could hurl city-block-sized chunks of glacial ice - INTACT - for hundreds of miles. The ice would be pulverized/vaporized at the impact site, even before any velocity/atmospheric effect.

Wow this is fascinating, I'd never heard of this before.

My vote is for a comet impact on the Laurentide ice sheet and these are the resulting ice chunks falling back to earth at the younger dryas event.

The asteroid theory seem to explain it best, and the similar depressions in Nebraska.

Thanks for this overview. I can't wait to share my theory with the world.

I agree with Zamora and Zelinka. They talk about how a meteorite struck the ice sheath which sent ice into ballistic arcs that crashed all over the US. There are bays in Nebraska, the East Coast, Ohio, etc. Most of the trajectories drawn from the orientations of the Bays point to the origin in the Upper Mid West and suggest multiple impacts on the ice sheets.

There are KZfaq presentations by Antonio Zamora that propose an explanation not mentioned here. Big chunks of ice, launched by a meteorite impacting the ice sheet somewhere near Michigan. Not saying that makes as much sense than the one offered in this video.

Always enjoy when Hank speaks, reminds me of my child days 😌

They're basically the same thing as the thousands of 'lagoons' that dot the arid areas of Australia (and the midlands of Tasmania). At least in the Australian case, aridity has a big part to play in their formation, actually rather similar to the climatic conditions that promote the formation of badlands, aka, nutrient-poor, easily eroded soils, generally too dry to support decent plant cover that's occasionally exposed to heavy rain allowing erosive forces to shape them before they dry out again, preventing vegetation from stabilising them. Generally in Australian cases, these form most often atop hills and higher land where there's less surrounding catchment to fill them and most sit in their own little endorheic basins atop these higher land areas. This is important because there needs to be enough catchment and heavy, sporadic rain cycles to fill them and allow the wind/wave action to shape them, but also a small enough surrounding catchment that they do not have regular inflows (which would cause them to spill and drain them, effectively destroying the formation). I noticed in the LiDAR scans that were shown of the Carolina Bays, that they too sit atop higher land areas with little to no surrounding catchment that could potentially erode outlets for them. In Tasmania where I'm from, good examples would be lagoon complexes like the Woodstock Lagoons (just west of Longford atop an aluvial ridge), the Ellinthorpe Lagoons west of Campbell Town (in a dry rainshadow valley) and Lake Tiberias near Parattah, the largest of these features on the island. Geological maps tend to refer to these little lagoons with sandy dunes on their eastern shores as "aeolian formations" as wind it the primary factor in their shaping. Worth noting too that most of these will become somewhat saline as, being endorheic, salts eroded from the surrounding land can never leave to the ocean and builds up over millennia. On the mainland, especially in the SW of Western Australia, they can often be seen in long chains, marking the routes of ancient rivers. These however had very different starting points, but shaped in the same way. Effectively, ancient rainfall was higher and broad meandering rivers filled the vast shallow valley floors with aluvium. As the climate dried, the rivers stopped flowing and the wind began to move these loose sands into scattered dunes that choked the original river channels. When sporadic deluges would hit the region, the water would be dammed up by the sand and cause ponds to form. These ponds would slowly be shaped by wind and waves into strings of little elliptical lakes. Just enough rainfall to fill them at times, never enough to reform the river and drain them.

Makes sense. Thank you.

My first reaction was meteors too, but the video shows how the ancient environment back then shaped the landscape….

There's been a number of papers written on this unusually interesting subject - Antonio Zamora does some great recaps of the alternate, Glacial Impact hypothesis here: kzfaq.info/get/bejne/pNaIjJue2pjMmIk.html A key point is if a medium sized meteor or comet hit a 2 mile thick glacier with a glancing blow, there'd be no crater left today after the glacier melted - but there might be secondary impacts where flying chunks of ice would hit any soft ground, and these would radiate out from the impact site - which the orientation of the Carolina Bays and the Nebraska Rainwater Basins seem to do nearly perfectly - sure it's not proof, but boy, it's a chin scratcher

92 years ago?! My grandpa was alive back then!

Great theory that is incorrect. The bays will be weathered away in another 20k years, and could have not been formed more than 30k years ago. They also align with the Nebraska "rainwater basins" pointing at the Great Lakes region, as do these. Research the Younger Dryas impact, the deliberate burial of Gobekli Tepi, and other things that occurred +/- 18 to 24k years ago. Most reputable researchers are slowly coming around and seeing this to be the best fit for the available data. Y'all should do a segment on the scoured scablands out West.

Hey SciShow Team, Great Video! Can you please provide a source for the The likely origin of the Carolina bays being chilly lakes similar to the thermokarst lakes in Alaska

Sooo....my hippie-dippy aunt was right when she said the sun would "cleanse her quartz crystals" 😅

Really thought provoking!!!

I strongly disagree.

This doesn't add up to what I have heard about them. The further north you go, the more west-east-ish they get. The further south you go, the more north-south-ish they get. Plus, this doesn't account for the bays in the midwest that face the opposite direction, running north-east to south-west rather than north-west to south-east like the ones on the coast are. The one researcher I listened to recons they were formed by a comet hitting the glacial ice around what is now the Great Lakes, launching large chunks of ice out where they landed, creating angled craters that, due to the soft, sandy soil, just filled back in due to liquifaction. And if you mark these on a map of the US, they make and arc which includes the ones in the midwest... a giant circle of them all pointing towards the direction the ice came from. But I do love you guys mentioned these because they are SO fascinating to me especially as a North Carolinian. My grandparents live in the middle of the state, far from the coast and I always thought it was odd they live off of a road called "Bayside". Look on google maps and there is a nice clean one just behind their house!!

I live in GA, and vacation in FL, SC, NC, VA and I've never heard of them! Thanks for sharing!

I went to a school for a while called Carolina Bays Academy… and I literally grew up in a Carolina Bay. And I never knew this. Super cool!

I think I will go with Gram Hancock's theory of how these formed not yours

The are in more than just the eastern states - they extend into Nebraska and can be found in north America, south of where the ice sheet was 12,500 years ago on unconsolidated land. Unfortunately, the luminescence method has real problems with this type of structure because of the way that it was formed. This hypothesis also doesn't explain why the bays in Nebraska point the other way - in reality, they point towards the great lakes where, during the ice age, there was still ice. A chunk of space stuff (probably rock but weighing as much as it is calculated to have done, it would have had the same sort of effect whether it had been made from iron, stone or ice) hit the ice there (where it was several kilometres thick) and then vaporised like almost all of them do but the resulting explosion from all of that energy, projected many tonnes of ice in variously sized chunks into the air and above, from where they rained down onto unconsolidated ground that had just bee liquefied due to the seismic waves from the original impact, where they then produced conical cavities which then all but filled in due to the ground being fluid at that instant. A space rock hitting some ice is a lot simpler than the explanation given in this video and Occam's Razor suggests that this is therefore more likely. Suggested viewing is: kzfaq.info/sun/PLmd4S3n7PlE2H5FYYASaLd-eM5DBE33Rz Antonio Zamora who has written a peer-reviewed paper on this very subject; and, regarding the evidence for there being an impact at all, kzfaq.info/get/bejne/fdyJnad90ZPLgKc.html Dr Martin Sweatman, analysis of the many papers surrounding this issue, including the erroneous conclusion that are repeated in the video above.

Never heard of these formations before. Thank you

"from the southeast to the northeast"?- explication requested

Just did a quick search of Carolina bays on YT and literally everything I found talked about the impact theory. Thermo-karst makes more sense to me.

Thank you SciShow for covering this. Carolina Bays are fascinating to me, and once upon a time, took me down the rabbit hole of bolide impact ejecta theories to actually researching it during grad school and finding much of what you have stated here. There is actually evidence of the bays in Delaware , NJ, and Long Island, as well as parts of Nebraska, and there have been some fascinating studies linking them in age to various marine isotope stages. Some of the more interesting ones to me (and the most damning to any ejecta theories) are the kind where you can find them overlapping each other and extant river systems. The latest I'd read had them being formed anywhere from 150kyo to 50kyo, but it's been a few years so hopefully your sources are more current. Super cool to finally see the real science (if only briefly) behind one of the more alluring YDIH (Younger Dryas Impact Hypothesis) pseudoscience swirling around.

Damn, i want the cold dry environment back please. I've had enough of these mosquito hellholes

People are really fanatical about this ice shotgun hypothesis. I get it. It's exciting and way more fun to think about. But reality is usually less exciting. That's subjective because it's interesting either way but you get what I'm saying.

Mmmm chili lake (homer gargling)

The wind action forming the sand edges is totally inconsistent with the fact the similar elliptical bays are also found in NEBRASKA. The theory is that a comet hit the earth around Saginaw Bay in the Great Lakes region where there was 1 mile thick ice sheet. The impact broke the ice sheet and then the remains were displaced in a butterfly pattern creating the Carolina Bays and the Nebraska bay features. When the ellipses directions are measured they all align and point to a central impact area in the Great Lakes. The wind action forming the sand bays over thousands of years is a very flawed and old theory but because it is unformitst and not catastrophic in nature, people have been very reluctant to look into this relatively new theory.

It was a great impact onto ice that when it hit it sent giant sized ice chunks the size of baseball fields

Speaking of burying, you buried The Lead: Quartz Crystals tell Time! 👀

I’m surprised the Younger Dryas Impact Hypothesis was not covered in detail and was so handily dismissed. A 3 km meteorite slamming into the Laurentide Ice Sheet above Michigan… ejecting ice boulders ballistically after flattening and igniting a wide swath of forest on its approach… then the boulders rain down at multiple times the speed of sound…. I appreciate these Antonio Zamora videos and perhaps others here will too: kzfaq.info/sun/PLmd4S3n7PlE1T2n7G4FxIwFqjU6vw-vbW

Search Randall Carlson Carolina Bays.

Hey, I thought these looked like Thermoklast lakes! It makes the Western Interior of Alaska look very strange when viewed from above!

Huh! 80,000 hours, eh? I think that's the first ad I've actually appreciated in.. I don't know... Five years? Thanks guys! I'll check them out!

Look into The Younger Dryas impact theory. Makes more sense than what Hank is spewing out.

Antonio Zamora has the most rigorous hypothesis. His KZfaq channel has dozens of videos describing every conceivable detail.

I am an airline pilot and I have been flying over this area for years, wondering is they were creator’s from a previous bombardment.

Virtually everything we have been told about science and history is mere speculation or outright lies.

They're _obviously_ acne scars from when the Earth was going through puberty, idk why this was even a question

There are similar shaped features called the Nebraska Rain Water Basins in Nebraska that point Southwest to Northeast. Both these and the Carolina Bays point to the same general area of Michigan's Lower Peninsula.

I was asking myself at first why I never saw any of these, since I live on the east coast, but when I saw that they exist in southern New Jersey, and I live in Connecticut, well, I’m too far north.

Yay I never catch a freshly dropped video! Happy to be here!

They are "bays" in many other states than on the East Coast. There are many in Alabama and Mississippi, there are some also in Nebraska (where they are called "Nebraska Rainwater Basins"), and others yet in Iowa, Oklahoma... even a few in Texas. They ALL have three things in common: 1. They are perfect ellipses (except those badly eroded away) 2. They have rims elevated by a few feet. 3. They have their greater axis all ligned up to a common area: the Great Lake region! By that I mean that the Bays located in Long Island have their long axis pointing WNW, those in Virginia NW, in Georgia NNW, in Alabama they point up North, In Oklahoma they point NE and in Nebraska ENE. Some Bays do point in the direction of prevailing winds, most DO NOT! They just cannot be thermokarst lakes for several reasons that just make this hypothesis impossible: a. Thermokarst lakes are NOT elliptical in shape... or just the odd one by chance. They are all sorts of shapes. Carolina Bays are perfect mathematical ellipses... except if eroded away, as already mentioned. b. They don't have elevated rims. c. Their greater axis point downslope... makes sense... water flows down by gravity. "Carolina Bays" don't... or only by chance. d. They physically cannot be on hillsides, but always in lower lands. Carolina Bays are routinely found on hillsides. e. Thermokarst lakes don't have rims, Carolina Bays do. f. Carolina Bays can overlap each other, with the one that was formed last having a complete rim, but having erased the rim of the one that was formed first at the area of overlap. Sometimes, 3 or even 4 of them overlap each other in an intricate pattern. Thermokarst lakes do not overlap each other. g. Thermokarst lakes are created by the melting of permafrost; they are therefore found mostly in northern locations such as Alaska, northern Canada, Siberia, etc. Have you ever heard of permafrost in southern Alabama or Texas???? Even during the glaciation maximum of 20'000 years ago, there was no permafrost anywhere that far South, not by a thousand miles. There are more reasons for Carolina Bays to be neither thermokarst lakes, nor formed by wind, but I shall stop here... So-called Carolina Bays are MUCH more likely to have been formed by ice boulders (some the size of stadiums) ejected by a large meteorite impact on the Laurentian ice sheet, some 13'000 years ago (exact timing still debatable... and definitely debated) in the Great Lakes region. THAT hypothesis convincingly and demonstrably explains ALL the features, locations, geographic orientations, etc of the Carolina Bays. Having said this, the scientific debate is raging between the various hypotheses, and I have been following it with a scientist's interest, all the way from Europe, for several years. I am just surprised that SciShow presented a couple of the hypotheses, but not what is arguably the likeliest one! For those willing to learn more on that hypothesis, KZfaq has dozens of most serious videos on the topic.

So how do they explain the opposite Lee pointing similar features in Nebraska? As is typical with paid for science, you left out the most intriguing idea which is being pelted from ice from the glacial mass following an impactor event, probably much younger than 90,000 years. Mirrored features in certain Nebraska regions feature the same characteristics.

2:32 _"They are the remnants of ancient chili lakes."_ Oh, my. Given the lyrics, "Oh, there's a lake of stew and of whiskey, too you can paddle all around 'em in a big canoe in the Big Rock Candy Mountains" ...it would seem that the Big Rock Candy Mountains were indeed a thing, unfortunately over 90,000 years ago! (Yes, sarcasm.)

I would have guessed they were kettle lakes, formed by the depressions left by stranded ice as the last glaciers retreated. This is an interesting theory though!

Randall Carlson sends his regards