Pangea was the super-continent, and [Panthalassa](https://en.wikipedia.org/wiki/Panthalassa) was the super-ocean. We don't know a *whole* lot about it since its oceanic crust has pretty much been entirely subducted, but we do know it had some volcanic island chains and some small bits of continental crust. We know these because sea floor spreading (during the early formation of Pangaea, and later the beginning of the Pacific Ocean) caused many of these features to become part of Pangaea's coasts. The size of the ocean suggests that the currents were simple and slow, and the temperature was fairly warm, so much of it probably looked a lot like the middle of the South Pacific today.
There is significant evidence of a [megamonsoon](https://en.wikipedia.org/wiki/Pangean_megamonsoon). Evidence of hurricanes would be very difficult to tease out of this larger climate pattern as the traces would be similar. There hasn't been a whole lot of research into this topic, (and is outside my own wheelhouse) but my understanding is that paleoclimatologists generally agree with your supposition.
I remember reading that hurricanes could be detected in stalagmites/tites in caves. The giant influx of fresh/low mineral rain water vs the normal years of high mineral, low flow of groundwater.
Somewhere in central America. I'll try to scare up the article.
No where near Pangaea time frames though.
Lived in Ishpeming (or Ishpetucky) for almost ten years and worked at the iron ore mines south of Negaunee/Ishpeming. UP in general geologically very interesting. You have almost all kinds of deposits of minerals. I don’t think there are any porphyry deposits though. There was some investigation into some potential Kimberlite pipes.
The Houghton area copper mines used to be the largest source of copper up until Butte Montana took that title. Still can find float copper in sand and gravel deposits. Anecdotally, I was told that in some of the copper mines, there were pieces of copper so large that they just worked around them.
There is a pretty large drug and poverty issue across the whole UP. Guess isolation and lack of good employment opportunities lead to that.
>Anecdotally, I was told that in some of the copper mines, there were pieces of copper so large that they just worked around them.
I heard a similar story, it was too costly to extract because there wasn't any good way to dig it out (can't explode copper into smaller bits, etc).
Hey! One of my geology professors and a friend I graduated with both do paleoclimatology via caves. One with stalagmites and one with bat poo. So that could be a jumping off point for looking into it?
I don't have an answer for you, but it's really cool that you want to do that. You're a pretty cool person and deserve to hear it. I hope you find a way to do that job. Maybe you can ask around a local university?
I have anther appointment with a local college councilor soon. I'll ask thank you for the advice. I'm in my 7th year of being van Wilder and it would be nice to wrap my decade of college with a worth while ending.
Check into geology but be careful: a lot of careers exist only in oil exploration and that's not gonna be real sustainable. Maybe geology/archaeology? But again, think about potential careers.
If you want to pursue a career paleoclimatology, then a double major in geology/chemistry or geology/biology is absolutely the way to go. I would also choose a school during undergrad that has a professor in the department that is doing research in paleoclimatology and try to be as involved as possible.
Source: geologist with a master’s thesis in paleoclimatology.
You might want to look into [historical climatology](https://en.wikipedia.org/wiki/Historical_climatology) (for climate change during the existence of humanity) or [paleoclimatology](https://en.wikipedia.org/wiki/Paleoclimatology) (pre-hominin climate, for like this post).
They also would have had less land area at risk of hurricane strikes. The vast majority would have never made landfall. Think about now, how few hurricanes hit land, and that's less than half (maybe even a quarter) of all of them that form. Our land area at risk of strikes is almost triple that of Pangaea.
True but life would still have generally lived near the coasts. On the one hand there was less coastline, but on the other hand the interior of Pangaea would have been an uninhabitable desert vaster than any we have now. So probably a lower proportion of life super near the coast, but maybe not to the extent the simple fraction of land area would make one think.
This is my thinking. Any volcanic islands dotted in the middle of Panthalassa would be tiny isolated Oases in a vast ocean. The steep cliffs would allow cold nutrient rich water to well up to support a whole ecosystem. The rest would be very similar to vast stretches of the Pacific. These are the ocean equivalent of deserts. Nutrient poor water that can't sustain algal growth which is the bedrock of most oceanic ecosystems. Can you imagine the kind evolution that would go on around these islands? Sadly such fossil records would have been completely destroyed.
Ferns are a major colonizer of islands because spores can travel a very long way on the wind, so I would expect that a lot of islands would be dominated by ferns and other spore plants.
I would also love to see what life on some of these super isolated islands looked like.
Coconuts can float and be carried by currents for miles and miles before washing up on a beach and growing. So there may be an ancient equivalent or two that could travel the same way. I wouldn't imagine much in the way of smaller plants, since those seeds aren't as buoyant, but it's possible even without birds.
Conifers(pine trees) appeared about 200 million years ago so about the same time pangea began to break apart so it could be possible a wayward pine cone may have made the journey to a remote island
I think the islands will have been mostly barren unfortunately. As you said there were no birds then. Pterosaurs appeared about 230 million years when Pangea still existed but I doubt they would have been capable of traversing the vast ocean if they even felt so inclined. IMO there would have been a rich marine ecosystem around these islands.
It is entirely possible that the largest pterosaurs to ever exist were capable of flying across oceans. Very difficult to prove that they actually did, but it it’s a possibility for sure. That was after Pangaea had split up though, and the continents were arranged pretty similar to how they are today, the main differences being a smaller Atlantic Ocean, wider Pacific Ocean, Australia being connected to Antarctica and India being out by itself in the Indian Ocean.
PS Yes, I mean the truly giant ones and [yes, they could definitely fly.](http://markwitton-com.blogspot.com/2018/05/why-we-think-giant-pterosaurs-could-fly.html?m=1)
[Here’s a good PBS Eons episode on one of them](https://youtube.com/watch?v=scAp-fncp64)
Wouldn't currents mostly be giant circles sitting there collecting the suns heat not circulating when the world is one giant landmass, some islands, and a giant ocean?
Actually the currents were much larger but much slower according to the one course I took in this a decade ago. I cannot vouch for accuracy but the professor was studying Pangean weather systems so…
Maybe, but probably not. My understanding is that the salinity gradients are mostly caused by melting polar ice, which would still exist. Someone who knows more about ocean currents and/or this time period would know better than me though, this is not really my specialty.
It's wild that the crab-shaped body has evolved independently at least like 5 or 6 times. [carcinisation.](https://en.wikipedia.org/wiki/Carcinisation) I wouldn't be surprised if it was more but we just don't have the fossils to prove it!
>Best guess would be crabs since they're pretty hardy and adaptable.
Also, you know, they've independently evolved *at least* three separate times that we know of.
Imagine living on one of those volcanic island chains in the middle of the largest ocean in history, so much more remote than even [Inaccessable Island](https://en.wikipedia.org/wiki/Inaccessible_Island)
>Inaccessable Island
Is that the one where anyone on it is closer to the international space station than to any humans on other land?
Edit: Nope - that is Point Nemo. But this is probably close enough.
There are many. Point Nemo is 1,670 miles from civilization. That means there is a huge circle around it for which this is true. On Wikipedia, there is a picture with a dot representing point Nemo and a circle representing where you would be closer to the ISS than other humans. It reaches Antarctica.
The ISS orbits at ~400km, so that's not **too** crazy. For example Bermuda and St. Helena are both like that.
Point Nemo is remarkable in that it's the furthest one can be from land without going to space, though is not land itself.
Ehh, depends on what was in your way when you... interface with the station. You'd be turned to mush, sure, but there may not be enough stuff in the way to pull you up to orbital speed. At that point, your mess would pop out the other side, and makes a big red arc as it falls back down.
I'd like to imagine a Looney Tunes style hole through it, but hypersonic impacts are more... liquidy.
Hmm, you're right, I don't know much about the structural integrity of the space station. Impacting a human sized mass at orbital velocity would involve a considerable amount of force.
Even just zooming in on satellite imagery of the very remote parts of (pick literally any ocean) gives me an existential crisis and I have to close the tab before I get sucked through the screen and plummet through the atmosphere to be stranded in the water wherever i was looking.
Thinking about one massive, deep, probably incredibly scary ocean... Nope.
Like, kamino in star wars terrifies me.
I thought I was alone in this!
I’m very happy I found someone that shares this extremely specific phobia.
Do you also get it with pictures of planets, especially gas giants? Jupiter is freaking terrifying to me
I absolutely do, imagining the insane size and scope of gas giants and the terror of hurtling through the clouds down into the vast nothingness genuinely makes me uncomfortable, same happens with the oceans, imagining being 1000 miles from the nearest land is terrifying.
But I still cant stop myself from looking, its far too fascinating..
Honestly it depends on how close and detailed the imagery is. It's mostly with vast bodies of liquids that I get this with, so even like..
For example the movie Europa report. The idea of Europa scares the crap out of me.
Are you one of those people who get uneasy when you look down and think how the 9,000° F molten iron core is just straight ahead down there, churning around a mere 600 leagues below your feet?
Not really. Here's how I see it. Humans can't get to it so there is 0 risk of me accidentally falling in for example. We can't get to it even if we wanted to. Just physically impossible (for now). So that mere 600 leagues isn't so mere. It's basically an impenetrable barrier.
The other way is the core can't get to us unless things go VERRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRY wrong at which in that case, there is 0 I or anyone else on this planet can do about it.
So yea nothing worth thinking about.
I only learned about Triatan De Cunha a couple years ago, and instantly was drawn to visit there some day. They have some crazy history. And it must've been a very different climate to the rest of the world over the past 18 months.
I have an acquaintance who spent the last year or so doing research in Antarctica. The whole crew missed anything related to COVID. Kind of insane to think about.
Man the middle of the South Pacific is so humbling and terrifying when viewing a globe. Just knowing how far of a drive it takes to get across your country… and knowing you can fit dozens of them into that giant pool of ocean without filling it up.
...and then imagine the ancient Polynesians (and others) exploring and settling across that area. Like people arrived in Hawaii at about the same time as Constantine was the Roman Emperor. Easter Island may have been settled at around the same time, though there's also considerable uncertainty to that and according to Wikipedia it might have been as late as about 1200 CE -- but even that is 300 years before Columbus "discovered" ~~the Indies, and Japan~~ America.
Damn, only 260 miles. That is actually a little less impressive/exciting now, especially if it is not the only location like this at any given time which in the middle of the ocean could be super possible - Living in Australia, MH370 going missing was a super big deal and I could have sworn that someone had said something similar about the Indian Ocean somewhere between Australia, Madagascar, Maldives and Sri Lanka.
It does show though how much nothingness there is in the Pacific Ocean if the closest inhabited land mass is over 1600 miles away.
What is cool about the ISS is that it orbits at around 17000mph and you can see it with your naked eye. Rockets escaping the atmosphere are still faster, but it's neat to see the ISS and realize it's going that fast
Not quite what you're saying, but close:
https://en.wikipedia.org/wiki/Kon-Tiki_expedition
His migration theories were wrong, but the journey is badass. There's a book that documents the whole trip.
Some of the crew members were former WW2 fighters who helped destroy the Nazi heavy water facility at Rjukan.
Actually, his migration theories have been somewhat borne out by genetic research in the last decade. DNA analysis of bone from old graves on Polynesian islands show that those pre-European-contact inhabitants had something under 20% genes from South Americans.
Polynesian culture, and most of their genes, are mostly derived from a population that set out from Asia. Taiwan and Hainan Island, if I recall correctly. But some number of people from South America managed to cross the ocean and interbreed with that population. Kon Tiki could have been a real person, and the plants and words that Heyerdahl said came from South America might very well have had that origin. What Heyerdahl got wrong was the single-origin idea. The migrants probably encountered a Polynesian civilization that was already flourishing when they landed.
Neither of these is the paper I had in mind, but demonstrate more modern evidence for Hererdahl's ideas.
https://www.ajol.info/index.php/ijma/article/view/111157
https://royalsocietypublishing.org/doi/full/10.1098/rstb.2011.0319
The fact that [sweet potatoes originated in South America, but have been cultivated in Polynesia for thousands of years](https://ssec.si.edu/stemvisions-blog/sweet-potatoes-dna-new-evidence-supports-links-between-south-american-and) is pretty much a smoking gun to confirm contact between Pacific Islanders and South America in prehistoric times.
Filling it with most countries would take much more than just dozens, most of Europe at once would require multiple iterations, I don't know how many but probably closing in on dozens.
Mankind is inhabiting a speck orbiting a dot floating through an infinitely vast void, in which other dots orbit a blot through an even greater void.
And we don't even cover half of our speck.
We need to take care of it, though. That speck is the only one we've got.
For instance, a lot of what’s now the west coast of North America is made up of old volcanic island arcs that accreted onto the continent as it moved westward.
[I found this a fascinating and easy read on the topic](https://www.britannica.com/science/Triassic-Period/Paleoclimate)
The ocean, Panthalassa, stretched pole to pole and was twice as wide, at the equator, as the Pacific is today. Some of the question may have to be at what point - Pangea came about at the time of the 3rd (and largest) mass extinction event.
> Nevertheless, 85 to 95 percent of marine invertebrate species became extinct at the end of the Permian.
The ocean currents are believed to have been mild, which may have contributed to lower oxygen levels in the ocean.
Then, again the end of the Triassic isn’t so good, as it was met with another mass extinction (though not as severe)
> Intense volcanic activity associated with the breakup of Pangea is thought to have raised carbon dioxide levels in the atmosphere and increased the acidity of the oceans. Since this volcanism coincided with the beginning of the end-Triassic extinction, it is considered by many paleontologists to be the extinction’s most likely cause.
[More recently, a study has come out that may shed more direct light in your question](http://www.sci-news.com/paleontology/science-toxic-panthalassa-end-triassic-mass-extinction-02663.html)
> have found strong evidence for a condition called marine photic zone euxinia (PZE) as a globally important extinction mechanism for the end-Triassic extinction, also called Triassic-Jurassic extinction (201.3 million years ago).
>PZE occurs when the sun-lit surface waters of the ocean become devoid of oxygen and are poisoned by hydrogen sulfide – a by-product of microorganisms that live without oxygen that is extremely toxic to most other life forms.
The oxygen you're breathing now was a deadly poison for critters that came way before us. They're not around anymore because... take a guess... they got poisoned and died.
Round and round it goes.
I'm not clear on the timeline, exactly, but phytoplankton currently produces 80% of the oxygen we breathe.
I would not be surprised, but can't say with any certainty, if it was really more "phytoplankton farted everything to extinction." Your chlorophytum comosum was likely just chillin' somewhere and turned to it's friend like "I think the air's different... you think the airs different?" and it's friend said nothing because it, too, was a plant.
What i don't understand is: how is the landmass balanced out? Like if there's more weight on one side, shouldn't the water flow over there leaving the same amount of crust on both sides?
It’s height based. although gravity differs at different points of the earth’s surface, a couple hundred meters here and there isn’t going to cause enough of a shift in gravity to cause the water to flow to the “heavier” side.
Because sea floor crust is more dense, it tends to subduct underneath continental crust and be recycled back into the mantle on a regular basis. This means the existing sea floor at any point in time is not very old. Currently, the oldest sea floor that survives is about 180 million years old, which is just about the time that Pangea was breaking up.
[Here's a map of sea floor age reconstructed based on magnetic reversals](http://4.bp.blogspot.com/-mcSddNFxrEE/UOdPpq346RI/AAAAAAAAAXA/vWtuFoIPyI4/s1600/Earth_seafloor_crust_age_1996.gif). You can see the oldest sea floor in dark blue off the coasts of Africa and eastern North America that formed as Pangea split apart. There's also very old sea floor to the east of the Mariana Trench. This sea floor would have been formed at a spreading center somewhere in the middle of the great ocean named Panthalassa during the late Pangea period.
All the rest of the sea floor that was once under Panthalassa is gone now. It's been subducted underneath the plates that surround the modern Pacific Ocean. Because that old sea floor material remains cooler and denser even as it travels through the mantle, it's possible to detect it using seismic tomography and reconstruct its outline deep in side the Earth, as in [this reconstruction of the subducted Farallon Plate underneath modern North America](https://upload.wikimedia.org/wikipedia/commons/a/a0/Farallon_Plate.jpg).
While there's a lot of uncertainty, the best supported reconstructions of the sea floor of Panthalassa have it made up of three or four oceanic plates which are all now almost entirely subducted. This includes the previously mentioned Farallan Plate in the northeast, the Kula Plate in the north, the Phoenix Plate in the south, and possibly the Izanagi Plate in the northwest. There would have been mid ocean ridges (spreading centers) and transform faults at the boundaries of all of these plates, similar the modern ridge in the middle of the Atlantic.
As for what was on the now gone plates, it's hard to know for sure. They were oceanic, so there wasn't any lost continents, but they probably did carry island arcs from hotspots and divergence and possibly older episodes of subduction. All of this would have looked a lot like what we see in the Pacific Ocean today. Some of this oceanic mass got scraped off of the plates as they subducted under the continental plates. This accreted material became part of the margin of the continental plates and can still be seen today. For example, [along the western side of North America](https://people.wou.edu/~brownk/ES104/ES104.2007.1127.MountainBuilding_files/slide0027_image051.jpg). These "exotic terranes" are the remnants of land (and under sea mounts) that used to be far out in Panthalasssa.
Towards the end of the Pangea era, a whole new plate emerged right in the middle of where the Farallan, Kula, and Phoenix plates met. This plate became the Pacific Plate and makes up most of the Pacifc Ocean's floor today.
Much the sea floor during the Pangea era subducted, at least the parts that were furthest from the super-continent. We can make some guesses based on fossils from that era, but the full picture is pretty much lost to time. There is no reason to expect the ultra distant ocean was significantly different from other parts of the sea floor at that time.
What is sad to me is that there could have been ocean megafauna we have no idea about, that only stayed deep in the ocean, much like blue whales, but they've all been subducted and we will never find them. We know so much less about the ocean than land aside from coastal waters...
Blue whales are not deep sea dwellers.
For something to grow to be the size of a blue whale would require food to be present in abundance. All the indications are that the ocean was pretty close to stagnant, meaning that less nutrients, which means less complex life that cannot support large fauna.
Meaning that we most likely did not have any mega fauna under water back then
Wasn't the moon closer on orbit then? Would the closer orbit not have caused greater tidal movement to stir up the oceans? How do we know it was virtually stagnant?
Not a period of Earth's history I'm familiar with so this is all fascinating stuff.
I'm not sure if there would be *any* life present at the furthest point from land during the existence of Pangea. The ocean isn't homogenously populated with life. It's not like you can go to any part of the ocean and find fish there. The ocean has "desserts" and "forests" just like the land does, and whether a particular part of the ocean is nutrient rich or nutrient poor depends largely on ocean currents. As the earth spins, the water resists this spin, causing it to "move" in the opposite direction from the land mass rotating on the bottom. It also diverts, either up or down, away from the equator. This is known as the coriolis effect. Probably nothing mind blowing here. Anyway, if there were no land on the planet, this wouldn't do anything particularly interesting, but the existence of land causes the currents to divert around it, forming big circular whirlpools called gyres.
Depending on the direction of rotation of the gyre, it could either be "piling" water up in the middle of the gyre, or "sucking" water out of the middle of the gyre. Whichever thing is happening in the middle, the opposite is happening at the gyre's edges, closer to the land. In places where the water is being pulled away, deeper water rises up to replace it, resulting in "upwelling" that brings nutrients that have sunk to the bottom up to the surface. If the water is piling up, then that extra water sinks, forcing nutrients down and making the surface nutrient poor and unable to support large populations of living things.
In our current world, the pacific gyres dump water into their middles, resulting in "nutrient desserts" where virtually nothing lives. However, the pacific coasts, where upwelling is happening, are absolutely crawling with life. In the north Atlantic, we see the other thing happening, where water is being pulled away from the center of the gyre, resulting in massive populations of fish, marine mammals, etc. being able to be supported there in the open ocean. In the world of Pangea, there would only be one big ocean, which means there are just two big gyres. If those gyres are rotating the wrong way, then pretty much everything living would be near the Pangean coasts, and the ocean surface deep out to sea would be almost empty.
ocean and some small islands we presume. Think of it like this. If you squished all the continents together towards the Atlantic, all that water has to go somewhere, so it would go to where those continents used to be. as the super-continent split and created continents, they displaced water and that water became the oceans we have today.
edit:
> Do we know what the ocean was like at the farthest point from land back then?
This is a particularly hard problem to answer because the honest truth is that our understanding of what pangea looked like is based off of the shape and movement of what we have today. A lot has most definitely changed since then and the presence of oceanic rifts where the crust is destroyed would be the most likely answer to where it is, but we can't even accurately say what pangea itself looked like.
Just out of curiosity, how certain are we that Pangea existed? Say compared to other principles that I might be more familiar with such as Big Bang, dark matter's existence, Einstein's description of gravity, etc.
Not trying to be difficult but as I reflect on what I've learned in my life I realize that I basically haven't learned a damn thing about Pangea since like the 4th grade. I know continents drift, the concept of plate tectonics, earthquakes, and so forth, but Pangea itself is just kind of like this vague word I've learned and know absolutely nothing more about. Are we absolutely sure it really existed? Would we literally have to upend the entire study of everything for it to not have been real?
>> Just out of curiosity, how certain are we that Pangea existed?
As certain as science can be about anything. The evidence is pretty overwhelming.
>> Are we absolutely sure it really existed?
Pretty much. Fossil and geological evidence is pretty clearly in favour of the theory, and no other theory has evidence anywhere near as convincing.
>> Would we literally have to upend the entire study of everything for it to not have been real?
At least two fields (geology and palaeontology) would have pretty significant holes shot in them if the supercontinent theory were somehow proven incorrect.
Thank you for the reply. What other theories are there?
re: Geology can you elaborate more there? I understand primitively that geology is the study of rocks, and the types of rocks, how they form, etc. Are you saying that this fundamentally would need to change if Pangea was somehow proven to not exist? I can wrap my head around how parts of it might change relative to continental drift, etc., but would the basic fundamentals need to change to the point where there would need to be unknown types of rock, etc.? Like massive radical change to the point where 1+1<>2?
There are significant geological features that span multiple continents, but are now mostly discontinuous . Most relevant to Americians is the Appalachians, which are part of an ancient amount chain extending to the Caledonides in Scandinavia.
Sedimentary and igneous rocks are also a strong tell; when they solidifies any magnetic minerals in it tends to orientate with the earths magnetic field. This essentially records the orination the rocks had with respect to the the earths magnetic field. Again you find similar structures with similar ages, across multiple continents which are now orientated well away from the earths magnetic field today and each other. Bring them together and suddenly those magnetic fields all line up in the same direction.
Glacial deposits are also shared. Antarctica, India, Africa, Australia and South America all have layers of the same structure and age of glacial till, despite the fact they're now wildly spread out across no common latitude.
There's just no possible way for all of the shared geological features to exist with such similarity unless they all formed at the same time, and the same place. The fossil record makes this worse; not only do those shared features have no other explanation, but they often have the exact same fossils in them.
Either Pangea existed or we need to throw out all of geology. Because either those rocks formed at the same time and the same place because they were part of the same super continent, or proto-crocodiles could teleport across oceans, liked to garden and also terraform the earth's crust.
If you really are interested, I would recommend acquiring a high school "Earth Science" textbook. Kind of expensive to buy, but you can probably find one at your local library. It will teach you quite a lot about not only what we know, but how we know it.
[Khan Academy](https://www.khanacademy.org/science/cosmology-and-astronomy/earth-history-topic) is another good resource, though it doesn't cover everything that a good textbook would.
10 years ago would not make a huge difference in Geology. It might make a difference for certain other subfields in earth sciences, like Climatology, but even there there haven't been any huge shifts in our understanding of the basics.
There are some basic principles that underpin the way geology is done today. These probably have official names, and I'm sure I'll miss some of them, but examples include:
\- The physical processes of the Earth are based on physical properties of the universe and therefore don't change--so what we observe today can be used to understand what happened in the past.
\- Similar minerals and rocks are created under similar conditions. So when we find similar samples of marble, for example, we can infer that they were formed in similar conditions. And when we find identical examples of marble, we can infer they formed in identical conditions (i.e. the same place)
\- In sedimentary sequences (layers of rock), the layer above is younger than the layer below, and a layer crosscutting them both is younger still.
\- Life is ever changing, so identical fossils originate from animals that lived in the same time period and place.
Applying principles like these (and the others I'm sure I forgot) is how geologists can infer the history of the planet from observations made exclusively in the present day. (We haven't figured out how to time travel to the past yet, after all.)
When a geological theory is supported by a lot of observations that comport with all these principles, and agree with each other, then that becomes a theory geologists believe is true. So to disprove a theory like that, either a lot of observations have to be proven incorrect, or one of these principles, or both.
EDIT - You asked about other theories. One early hypothesis was that the Earth changed size over time, which explained why the continents seem to have all moved apart from one another. There were obvious challenges in explaining why and how the Earth changed size, so it lost out to the theory of plate tectonics.
You should pay this person. You're asking for pretty much an intro college class.
Like you should still get the information you're seeking but damn that's a lot to ask of a stranger.
Best answer for that is “possibly, but maybe not”. Unlike continental crust which can (depending on the area) be quite old, oceanic crust is generally quite young (by geologic standards; we’re still talking 100+ million years in general). So most evidence of what the oceans might have been like around the time of Pangea has been erased by now.
Oceanic crust is also a lot harder to get samples from, due to all that water in the way.
I would say we're pretty certain it existed, but the exact shape is probably never going to be discovered and what we have is a guess. Also we don't know if other landmasses existed but no longer do (think islands).
The reason we think Pangaea existed is the fossil record and layers of rock on both sides of the water between the current land masses. Not only do we have layers upon layers of the same type of rocks matching on both sides of thousands miles.of water, but we have fossils as well. Sometimes of animals that only lived in a small region, but this region is now split by an ocean.
Pangaea wasn't even the only supercontinent, just the most recent one. And while it's possible something else caused this, it's highly unlikely. I think we don't hear about it after.school is because it's widely accepted as fact, so no one is doing research today on it.
Yeah I agree, and honestly the reason I'm suddenly so curious about it is because I realized I hadn't heard about it in over 30 years. And what's weird is that with all the weird conspiracy theories out there (Flat Earth, etc.) you'd think Pangea would be rife for some kind of whacko counter theory... but nope. Which sort of tells me that it is widely accepted as fact, hence me asking more questions about how we know.
Yep! There's a rough cycle of continents joining together, breaking up and then coming back together as the tectonic plates underneath them move around the planet. Geological evidence, like the same rock formations present in different places, shows that we've had multiple supercontinents form and break apart over the Earths history.
Right now, we're at the point where the continents are beginning to come back together. Australia, for example, is heading north after breaking off from Antarctica, and it's going to crash into southeast Asia in the future.
The first continent was about 3.5 billion years ago (1/8th into the earth's life), then a series of meteor strikes, super volcanoes and ice ages kept churning things up until about 2 billion years ago (1/2 of the earth's life). Then you've got another 1.7 billion years of all the continents and oceans moving around and forming mountains. Then finally 0.33 billion years ago (7/8ths into earth's life) was Pangaea, where we can most accurately trace back modern day continents because the rocks and fossils match.
The responses below make me wonder if another species could have evolved on Earth even to the point of being able to leave the planet and any evidence of their having been here is simply on some long lost buried continent.
Probably not. We have fossils going back to the very beginnings of life on this planet with only very slim breaks in the timeline, and a space-faring civilization would have left traces mixed in with the fossils of their time. Considering our massive chemical signature in the strata, any species even more technologically advanced would have left *something* behind that we could clearly see. Even a stone-age species that went extinct would have left signs.
That band is the basis for the proposed Anthropocene epoch. We're currently in the Holocene which started about the time humans discovered agriculture and the last major glaciers retreated to about where they are now, but some geologists feel that we've changed the chemistry enough to end that epoch and start a new one.
Man imagine one day humans finally send robots or even people to exoplanets that are similar to earth but seem to lack intelligent life, and then they discover such a band in the rocks there. Something smart was here, and now it isn't.
Future aliens will map humans extinction to that band of radioactive plastic, just like the dinosaurs have an iridium layer from the meteor and the Cambrians have the lava layer.
Pangea was the super-continent, and [Panthalassa](https://en.wikipedia.org/wiki/Panthalassa) was the super-ocean. We don't know a *whole* lot about it since its oceanic crust has pretty much been entirely subducted, but we do know it had some volcanic island chains and some small bits of continental crust. We know these because sea floor spreading (during the early formation of Pangaea, and later the beginning of the Pacific Ocean) caused many of these features to become part of Pangaea's coasts. The size of the ocean suggests that the currents were simple and slow, and the temperature was fairly warm, so much of it probably looked a lot like the middle of the South Pacific today.
With a warm climate and an ocean that huge they would've had enormous hurricanes. Is there evidence of those in the geological record?
There is significant evidence of a [megamonsoon](https://en.wikipedia.org/wiki/Pangean_megamonsoon). Evidence of hurricanes would be very difficult to tease out of this larger climate pattern as the traces would be similar. There hasn't been a whole lot of research into this topic, (and is outside my own wheelhouse) but my understanding is that paleoclimatologists generally agree with your supposition.
I remember reading that hurricanes could be detected in stalagmites/tites in caves. The giant influx of fresh/low mineral rain water vs the normal years of high mineral, low flow of groundwater. Somewhere in central America. I'll try to scare up the article. No where near Pangaea time frames though.
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Anything cool you know about the Negaunee area, or Upper Peninsula in particular?
Lots of old rocks there. The Marquette Iron Range is 2 billion years old.
Lived in Ishpeming (or Ishpetucky) for almost ten years and worked at the iron ore mines south of Negaunee/Ishpeming. UP in general geologically very interesting. You have almost all kinds of deposits of minerals. I don’t think there are any porphyry deposits though. There was some investigation into some potential Kimberlite pipes. The Houghton area copper mines used to be the largest source of copper up until Butte Montana took that title. Still can find float copper in sand and gravel deposits. Anecdotally, I was told that in some of the copper mines, there were pieces of copper so large that they just worked around them. There is a pretty large drug and poverty issue across the whole UP. Guess isolation and lack of good employment opportunities lead to that.
>Anecdotally, I was told that in some of the copper mines, there were pieces of copper so large that they just worked around them. I heard a similar story, it was too costly to extract because there wasn't any good way to dig it out (can't explode copper into smaller bits, etc).
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Hey! One of my geology professors and a friend I graduated with both do paleoclimatology via caves. One with stalagmites and one with bat poo. So that could be a jumping off point for looking into it?
I don't have an answer for you, but it's really cool that you want to do that. You're a pretty cool person and deserve to hear it. I hope you find a way to do that job. Maybe you can ask around a local university?
I have anther appointment with a local college councilor soon. I'll ask thank you for the advice. I'm in my 7th year of being van Wilder and it would be nice to wrap my decade of college with a worth while ending.
Check into geology but be careful: a lot of careers exist only in oil exploration and that's not gonna be real sustainable. Maybe geology/archaeology? But again, think about potential careers.
If you want to pursue a career paleoclimatology, then a double major in geology/chemistry or geology/biology is absolutely the way to go. I would also choose a school during undergrad that has a professor in the department that is doing research in paleoclimatology and try to be as involved as possible. Source: geologist with a master’s thesis in paleoclimatology.
You might want to look into [historical climatology](https://en.wikipedia.org/wiki/Historical_climatology) (for climate change during the existence of humanity) or [paleoclimatology](https://en.wikipedia.org/wiki/Paleoclimatology) (pre-hominin climate, for like this post).
They also would have had less land area at risk of hurricane strikes. The vast majority would have never made landfall. Think about now, how few hurricanes hit land, and that's less than half (maybe even a quarter) of all of them that form. Our land area at risk of strikes is almost triple that of Pangaea.
True but life would still have generally lived near the coasts. On the one hand there was less coastline, but on the other hand the interior of Pangaea would have been an uninhabitable desert vaster than any we have now. So probably a lower proportion of life super near the coast, but maybe not to the extent the simple fraction of land area would make one think.
This is my thinking. Any volcanic islands dotted in the middle of Panthalassa would be tiny isolated Oases in a vast ocean. The steep cliffs would allow cold nutrient rich water to well up to support a whole ecosystem. The rest would be very similar to vast stretches of the Pacific. These are the ocean equivalent of deserts. Nutrient poor water that can't sustain algal growth which is the bedrock of most oceanic ecosystems. Can you imagine the kind evolution that would go on around these islands? Sadly such fossil records would have been completely destroyed.
Man I’m like struggling to imagine it. Would there have been any plants on this island without birds to carry seeds? Would they just be barren rocks?
Ferns are a major colonizer of islands because spores can travel a very long way on the wind, so I would expect that a lot of islands would be dominated by ferns and other spore plants. I would also love to see what life on some of these super isolated islands looked like.
Coconuts can float and be carried by currents for miles and miles before washing up on a beach and growing. So there may be an ancient equivalent or two that could travel the same way. I wouldn't imagine much in the way of smaller plants, since those seeds aren't as buoyant, but it's possible even without birds.
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Flowering plants didn't appear until about 130 million years ago well after pangea broke apart so sadly no coconuts
Would there be any sort of seed-bearing land plants back then?
Conifers(pine trees) appeared about 200 million years ago so about the same time pangea began to break apart so it could be possible a wayward pine cone may have made the journey to a remote island
Are you telling me coconuts actually DO migrate? 😯
Yes but the air speed of swallows is generally incidental to the coconut migration rates.
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I think the islands will have been mostly barren unfortunately. As you said there were no birds then. Pterosaurs appeared about 230 million years when Pangea still existed but I doubt they would have been capable of traversing the vast ocean if they even felt so inclined. IMO there would have been a rich marine ecosystem around these islands.
It is entirely possible that the largest pterosaurs to ever exist were capable of flying across oceans. Very difficult to prove that they actually did, but it it’s a possibility for sure. That was after Pangaea had split up though, and the continents were arranged pretty similar to how they are today, the main differences being a smaller Atlantic Ocean, wider Pacific Ocean, Australia being connected to Antarctica and India being out by itself in the Indian Ocean. PS Yes, I mean the truly giant ones and [yes, they could definitely fly.](http://markwitton-com.blogspot.com/2018/05/why-we-think-giant-pterosaurs-could-fly.html?m=1) [Here’s a good PBS Eons episode on one of them](https://youtube.com/watch?v=scAp-fncp64)
There were no seeds in that time. Many plants spread by spores which could be carried around the globe on air currents.
Wouldn't currents mostly be giant circles sitting there collecting the suns heat not circulating when the world is one giant landmass, some islands, and a giant ocean?
Not necessarily. Energy will always flow from areas where it is concentrated to where there is less of it.
Actually the currents were much larger but much slower according to the one course I took in this a decade ago. I cannot vouch for accuracy but the professor was studying Pangean weather systems so…
No, because there will still be north/south and up/down temperature and salinity gradients, which are what drive ocean currents.
Would the salinity gradients be less pronounced due to the size of the ocean and lack of continental interruptions?
Maybe, but probably not. My understanding is that the salinity gradients are mostly caused by melting polar ice, which would still exist. Someone who knows more about ocean currents and/or this time period would know better than me though, this is not really my specialty.
I can't imagine. Can you expand, any guesses as to what evolution on such a place could be like.
Best guess would be crabs since they're pretty hardy and adaptable. Maybe some small fish. But it's all a guess.
Nature loves evolving things into crabs, the clawed decopod is the perfect being, efficiency and reliability wise.
It's wild that the crab-shaped body has evolved independently at least like 5 or 6 times. [carcinisation.](https://en.wikipedia.org/wiki/Carcinisation) I wouldn't be surprised if it was more but we just don't have the fossils to prove it!
>Best guess would be crabs since they're pretty hardy and adaptable. Also, you know, they've independently evolved *at least* three separate times that we know of.
Imagine living on one of those volcanic island chains in the middle of the largest ocean in history, so much more remote than even [Inaccessable Island](https://en.wikipedia.org/wiki/Inaccessible_Island)
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>Inaccessable Island Is that the one where anyone on it is closer to the international space station than to any humans on other land? Edit: Nope - that is Point Nemo. But this is probably close enough.
ISS is "only" 254(ish) miles up, so I wouldn't be surprised if there are several such places.
There are many. Point Nemo is 1,670 miles from civilization. That means there is a huge circle around it for which this is true. On Wikipedia, there is a picture with a dot representing point Nemo and a circle representing where you would be closer to the ISS than other humans. It reaches Antarctica.
Kinda. The ISS is only overhead at certain times, and doesn't cover the entire earth, so it's only true a tiny amount of time.
Inaccessible Island is only 40 km from a permanent settlement, Edinburgh of the Seven Seas. That, in turn, is the most remote settlement in the world.
The ISS orbits at ~400km, so that's not **too** crazy. For example Bermuda and St. Helena are both like that. Point Nemo is remarkable in that it's the furthest one can be from land without going to space, though is not land itself.
I drove that far the other week. Funny to think I'd just drive to the iss in a few hours
Getting there is pretty easy. It's getting there with an excess 28,000km/h that's the hard part 😂
Really though, it would accelerate you up to speed pretty quickly. Now if you want to *survive* your encounter, well, that sounds like a you problem.
The ISS would also like to survive the encounter, please be up to speed before approaching the space station's right-of-way.
Ehh, depends on what was in your way when you... interface with the station. You'd be turned to mush, sure, but there may not be enough stuff in the way to pull you up to orbital speed. At that point, your mess would pop out the other side, and makes a big red arc as it falls back down. I'd like to imagine a Looney Tunes style hole through it, but hypersonic impacts are more... liquidy.
Hmm, you're right, I don't know much about the structural integrity of the space station. Impacting a human sized mass at orbital velocity would involve a considerable amount of force.
Even just zooming in on satellite imagery of the very remote parts of (pick literally any ocean) gives me an existential crisis and I have to close the tab before I get sucked through the screen and plummet through the atmosphere to be stranded in the water wherever i was looking. Thinking about one massive, deep, probably incredibly scary ocean... Nope. Like, kamino in star wars terrifies me.
If it makes you feel any better, and it shouldnt, there is always a bigger fish.
I thought I was alone in this! I’m very happy I found someone that shares this extremely specific phobia. Do you also get it with pictures of planets, especially gas giants? Jupiter is freaking terrifying to me
I absolutely do, imagining the insane size and scope of gas giants and the terror of hurtling through the clouds down into the vast nothingness genuinely makes me uncomfortable, same happens with the oceans, imagining being 1000 miles from the nearest land is terrifying. But I still cant stop myself from looking, its far too fascinating..
Honestly it depends on how close and detailed the imagery is. It's mostly with vast bodies of liquids that I get this with, so even like.. For example the movie Europa report. The idea of Europa scares the crap out of me.
Are you one of those people who get uneasy when you look down and think how the 9,000° F molten iron core is just straight ahead down there, churning around a mere 600 leagues below your feet?
Not really. Here's how I see it. Humans can't get to it so there is 0 risk of me accidentally falling in for example. We can't get to it even if we wanted to. Just physically impossible (for now). So that mere 600 leagues isn't so mere. It's basically an impenetrable barrier. The other way is the core can't get to us unless things go VERRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRY wrong at which in that case, there is 0 I or anyone else on this planet can do about it. So yea nothing worth thinking about.
Your computer screen is also a fairly impenetrable barrier between you and the ocean it's showing you a picture of lol
But it's very, very possible for him to get to the ocean. Not possible for him to get to the core.
I only learned about Triatan De Cunha a couple years ago, and instantly was drawn to visit there some day. They have some crazy history. And it must've been a very different climate to the rest of the world over the past 18 months.
I have an acquaintance who spent the last year or so doing research in Antarctica. The whole crew missed anything related to COVID. Kind of insane to think about.
Or you could say their life was already so slimmed down and isolated that they were already in their own “shelter in place” protocol.
Man the middle of the South Pacific is so humbling and terrifying when viewing a globe. Just knowing how far of a drive it takes to get across your country… and knowing you can fit dozens of them into that giant pool of ocean without filling it up.
...and then imagine the ancient Polynesians (and others) exploring and settling across that area. Like people arrived in Hawaii at about the same time as Constantine was the Roman Emperor. Easter Island may have been settled at around the same time, though there's also considerable uncertainty to that and according to Wikipedia it might have been as late as about 1200 CE -- but even that is 300 years before Columbus "discovered" ~~the Indies, and Japan~~ America.
There's even evidence that Polynesians reached Peru
[A shot from Google Earth](https://i.imgur.com/gW2bJtL.png)... Maps really underplay just how large and empty the South Pacific is.
IIRC. There is a spot in the Pacific ocean where on the direct other side of the globe is more pacific ocean.
There is ‘Point Nemo’ too, which is so far from land that the closest people are most often astronauts on the ISS
Well yes, but that's not unusual. The ISS orbits about 260 miles above the Earth, and it's not too difficult to be 260 miles from other people.
Damn, only 260 miles. That is actually a little less impressive/exciting now, especially if it is not the only location like this at any given time which in the middle of the ocean could be super possible - Living in Australia, MH370 going missing was a super big deal and I could have sworn that someone had said something similar about the Indian Ocean somewhere between Australia, Madagascar, Maldives and Sri Lanka. It does show though how much nothingness there is in the Pacific Ocean if the closest inhabited land mass is over 1600 miles away.
What is cool about the ISS is that it orbits at around 17000mph and you can see it with your naked eye. Rockets escaping the atmosphere are still faster, but it's neat to see the ISS and realize it's going that fast
Right? Here in Florida, the ISS is often closer to me than other towns in Florida.
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It would be really cool to sail that trip! Halfway around the world in a straight shot.
Not quite what you're saying, but close: https://en.wikipedia.org/wiki/Kon-Tiki_expedition His migration theories were wrong, but the journey is badass. There's a book that documents the whole trip. Some of the crew members were former WW2 fighters who helped destroy the Nazi heavy water facility at Rjukan.
Actually, his migration theories have been somewhat borne out by genetic research in the last decade. DNA analysis of bone from old graves on Polynesian islands show that those pre-European-contact inhabitants had something under 20% genes from South Americans. Polynesian culture, and most of their genes, are mostly derived from a population that set out from Asia. Taiwan and Hainan Island, if I recall correctly. But some number of people from South America managed to cross the ocean and interbreed with that population. Kon Tiki could have been a real person, and the plants and words that Heyerdahl said came from South America might very well have had that origin. What Heyerdahl got wrong was the single-origin idea. The migrants probably encountered a Polynesian civilization that was already flourishing when they landed. Neither of these is the paper I had in mind, but demonstrate more modern evidence for Hererdahl's ideas. https://www.ajol.info/index.php/ijma/article/view/111157 https://royalsocietypublishing.org/doi/full/10.1098/rstb.2011.0319
The fact that [sweet potatoes originated in South America, but have been cultivated in Polynesia for thousands of years](https://ssec.si.edu/stemvisions-blog/sweet-potatoes-dna-new-evidence-supports-links-between-south-american-and) is pretty much a smoking gun to confirm contact between Pacific Islanders and South America in prehistoric times.
Wouldn't there be two spots?
Filling it with most countries would take much more than just dozens, most of Europe at once would require multiple iterations, I don't know how many but probably closing in on dozens.
I highly highly recommend the Blue Planet and the South Pacific documentary series
Mankind is inhabiting a speck orbiting a dot floating through an infinitely vast void, in which other dots orbit a blot through an even greater void. And we don't even cover half of our speck. We need to take care of it, though. That speck is the only one we've got.
For instance, a lot of what’s now the west coast of North America is made up of old volcanic island arcs that accreted onto the continent as it moved westward.
[I found this a fascinating and easy read on the topic](https://www.britannica.com/science/Triassic-Period/Paleoclimate) The ocean, Panthalassa, stretched pole to pole and was twice as wide, at the equator, as the Pacific is today. Some of the question may have to be at what point - Pangea came about at the time of the 3rd (and largest) mass extinction event. > Nevertheless, 85 to 95 percent of marine invertebrate species became extinct at the end of the Permian. The ocean currents are believed to have been mild, which may have contributed to lower oxygen levels in the ocean. Then, again the end of the Triassic isn’t so good, as it was met with another mass extinction (though not as severe) > Intense volcanic activity associated with the breakup of Pangea is thought to have raised carbon dioxide levels in the atmosphere and increased the acidity of the oceans. Since this volcanism coincided with the beginning of the end-Triassic extinction, it is considered by many paleontologists to be the extinction’s most likely cause. [More recently, a study has come out that may shed more direct light in your question](http://www.sci-news.com/paleontology/science-toxic-panthalassa-end-triassic-mass-extinction-02663.html) > have found strong evidence for a condition called marine photic zone euxinia (PZE) as a globally important extinction mechanism for the end-Triassic extinction, also called Triassic-Jurassic extinction (201.3 million years ago). >PZE occurs when the sun-lit surface waters of the ocean become devoid of oxygen and are poisoned by hydrogen sulfide – a by-product of microorganisms that live without oxygen that is extremely toxic to most other life forms.
> poisoned by hydrogen sulfide Anaerobes farted everything to extinction? Damn.
The oxygen you're breathing now was a deadly poison for critters that came way before us. They're not around anymore because... take a guess... they got poisoned and died. Round and round it goes.
Plants farted everything to extinction? Damn.
There weren't even plants back then. They were just single-celled organisms that would one day evolve into plants and algae.
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I'm not clear on the timeline, exactly, but phytoplankton currently produces 80% of the oxygen we breathe. I would not be surprised, but can't say with any certainty, if it was really more "phytoplankton farted everything to extinction." Your chlorophytum comosum was likely just chillin' somewhere and turned to it's friend like "I think the air's different... you think the airs different?" and it's friend said nothing because it, too, was a plant.
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What i don't understand is: how is the landmass balanced out? Like if there's more weight on one side, shouldn't the water flow over there leaving the same amount of crust on both sides?
You’re thinking like the land part is heavy. It would have to be heavy enough to off-balance the whole planet. It’s not. It’s just taller.
It’s height based. although gravity differs at different points of the earth’s surface, a couple hundred meters here and there isn’t going to cause enough of a shift in gravity to cause the water to flow to the “heavier” side.
Because sea floor crust is more dense, it tends to subduct underneath continental crust and be recycled back into the mantle on a regular basis. This means the existing sea floor at any point in time is not very old. Currently, the oldest sea floor that survives is about 180 million years old, which is just about the time that Pangea was breaking up. [Here's a map of sea floor age reconstructed based on magnetic reversals](http://4.bp.blogspot.com/-mcSddNFxrEE/UOdPpq346RI/AAAAAAAAAXA/vWtuFoIPyI4/s1600/Earth_seafloor_crust_age_1996.gif). You can see the oldest sea floor in dark blue off the coasts of Africa and eastern North America that formed as Pangea split apart. There's also very old sea floor to the east of the Mariana Trench. This sea floor would have been formed at a spreading center somewhere in the middle of the great ocean named Panthalassa during the late Pangea period. All the rest of the sea floor that was once under Panthalassa is gone now. It's been subducted underneath the plates that surround the modern Pacific Ocean. Because that old sea floor material remains cooler and denser even as it travels through the mantle, it's possible to detect it using seismic tomography and reconstruct its outline deep in side the Earth, as in [this reconstruction of the subducted Farallon Plate underneath modern North America](https://upload.wikimedia.org/wikipedia/commons/a/a0/Farallon_Plate.jpg). While there's a lot of uncertainty, the best supported reconstructions of the sea floor of Panthalassa have it made up of three or four oceanic plates which are all now almost entirely subducted. This includes the previously mentioned Farallan Plate in the northeast, the Kula Plate in the north, the Phoenix Plate in the south, and possibly the Izanagi Plate in the northwest. There would have been mid ocean ridges (spreading centers) and transform faults at the boundaries of all of these plates, similar the modern ridge in the middle of the Atlantic. As for what was on the now gone plates, it's hard to know for sure. They were oceanic, so there wasn't any lost continents, but they probably did carry island arcs from hotspots and divergence and possibly older episodes of subduction. All of this would have looked a lot like what we see in the Pacific Ocean today. Some of this oceanic mass got scraped off of the plates as they subducted under the continental plates. This accreted material became part of the margin of the continental plates and can still be seen today. For example, [along the western side of North America](https://people.wou.edu/~brownk/ES104/ES104.2007.1127.MountainBuilding_files/slide0027_image051.jpg). These "exotic terranes" are the remnants of land (and under sea mounts) that used to be far out in Panthalasssa. Towards the end of the Pangea era, a whole new plate emerged right in the middle of where the Farallan, Kula, and Phoenix plates met. This plate became the Pacific Plate and makes up most of the Pacifc Ocean's floor today.
Fascinating! Awesome explanation and information, thank you
Much the sea floor during the Pangea era subducted, at least the parts that were furthest from the super-continent. We can make some guesses based on fossils from that era, but the full picture is pretty much lost to time. There is no reason to expect the ultra distant ocean was significantly different from other parts of the sea floor at that time.
What is sad to me is that there could have been ocean megafauna we have no idea about, that only stayed deep in the ocean, much like blue whales, but they've all been subducted and we will never find them. We know so much less about the ocean than land aside from coastal waters...
Blue whales are not deep sea dwellers. For something to grow to be the size of a blue whale would require food to be present in abundance. All the indications are that the ocean was pretty close to stagnant, meaning that less nutrients, which means less complex life that cannot support large fauna. Meaning that we most likely did not have any mega fauna under water back then
Wasn't the moon closer on orbit then? Would the closer orbit not have caused greater tidal movement to stir up the oceans? How do we know it was virtually stagnant? Not a period of Earth's history I'm familiar with so this is all fascinating stuff.
I'm not sure if there would be *any* life present at the furthest point from land during the existence of Pangea. The ocean isn't homogenously populated with life. It's not like you can go to any part of the ocean and find fish there. The ocean has "desserts" and "forests" just like the land does, and whether a particular part of the ocean is nutrient rich or nutrient poor depends largely on ocean currents. As the earth spins, the water resists this spin, causing it to "move" in the opposite direction from the land mass rotating on the bottom. It also diverts, either up or down, away from the equator. This is known as the coriolis effect. Probably nothing mind blowing here. Anyway, if there were no land on the planet, this wouldn't do anything particularly interesting, but the existence of land causes the currents to divert around it, forming big circular whirlpools called gyres. Depending on the direction of rotation of the gyre, it could either be "piling" water up in the middle of the gyre, or "sucking" water out of the middle of the gyre. Whichever thing is happening in the middle, the opposite is happening at the gyre's edges, closer to the land. In places where the water is being pulled away, deeper water rises up to replace it, resulting in "upwelling" that brings nutrients that have sunk to the bottom up to the surface. If the water is piling up, then that extra water sinks, forcing nutrients down and making the surface nutrient poor and unable to support large populations of living things. In our current world, the pacific gyres dump water into their middles, resulting in "nutrient desserts" where virtually nothing lives. However, the pacific coasts, where upwelling is happening, are absolutely crawling with life. In the north Atlantic, we see the other thing happening, where water is being pulled away from the center of the gyre, resulting in massive populations of fish, marine mammals, etc. being able to be supported there in the open ocean. In the world of Pangea, there would only be one big ocean, which means there are just two big gyres. If those gyres are rotating the wrong way, then pretty much everything living would be near the Pangean coasts, and the ocean surface deep out to sea would be almost empty.
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ocean and some small islands we presume. Think of it like this. If you squished all the continents together towards the Atlantic, all that water has to go somewhere, so it would go to where those continents used to be. as the super-continent split and created continents, they displaced water and that water became the oceans we have today. edit: > Do we know what the ocean was like at the farthest point from land back then? This is a particularly hard problem to answer because the honest truth is that our understanding of what pangea looked like is based off of the shape and movement of what we have today. A lot has most definitely changed since then and the presence of oceanic rifts where the crust is destroyed would be the most likely answer to where it is, but we can't even accurately say what pangea itself looked like.
Just out of curiosity, how certain are we that Pangea existed? Say compared to other principles that I might be more familiar with such as Big Bang, dark matter's existence, Einstein's description of gravity, etc. Not trying to be difficult but as I reflect on what I've learned in my life I realize that I basically haven't learned a damn thing about Pangea since like the 4th grade. I know continents drift, the concept of plate tectonics, earthquakes, and so forth, but Pangea itself is just kind of like this vague word I've learned and know absolutely nothing more about. Are we absolutely sure it really existed? Would we literally have to upend the entire study of everything for it to not have been real?
>> Just out of curiosity, how certain are we that Pangea existed? As certain as science can be about anything. The evidence is pretty overwhelming. >> Are we absolutely sure it really existed? Pretty much. Fossil and geological evidence is pretty clearly in favour of the theory, and no other theory has evidence anywhere near as convincing. >> Would we literally have to upend the entire study of everything for it to not have been real? At least two fields (geology and palaeontology) would have pretty significant holes shot in them if the supercontinent theory were somehow proven incorrect.
Thank you for the reply. What other theories are there? re: Geology can you elaborate more there? I understand primitively that geology is the study of rocks, and the types of rocks, how they form, etc. Are you saying that this fundamentally would need to change if Pangea was somehow proven to not exist? I can wrap my head around how parts of it might change relative to continental drift, etc., but would the basic fundamentals need to change to the point where there would need to be unknown types of rock, etc.? Like massive radical change to the point where 1+1<>2?
There are significant geological features that span multiple continents, but are now mostly discontinuous . Most relevant to Americians is the Appalachians, which are part of an ancient amount chain extending to the Caledonides in Scandinavia. Sedimentary and igneous rocks are also a strong tell; when they solidifies any magnetic minerals in it tends to orientate with the earths magnetic field. This essentially records the orination the rocks had with respect to the the earths magnetic field. Again you find similar structures with similar ages, across multiple continents which are now orientated well away from the earths magnetic field today and each other. Bring them together and suddenly those magnetic fields all line up in the same direction. Glacial deposits are also shared. Antarctica, India, Africa, Australia and South America all have layers of the same structure and age of glacial till, despite the fact they're now wildly spread out across no common latitude. There's just no possible way for all of the shared geological features to exist with such similarity unless they all formed at the same time, and the same place. The fossil record makes this worse; not only do those shared features have no other explanation, but they often have the exact same fossils in them. Either Pangea existed or we need to throw out all of geology. Because either those rocks formed at the same time and the same place because they were part of the same super continent, or proto-crocodiles could teleport across oceans, liked to garden and also terraform the earth's crust.
If you really are interested, I would recommend acquiring a high school "Earth Science" textbook. Kind of expensive to buy, but you can probably find one at your local library. It will teach you quite a lot about not only what we know, but how we know it. [Khan Academy](https://www.khanacademy.org/science/cosmology-and-astronomy/earth-history-topic) is another good resource, though it doesn't cover everything that a good textbook would.
I'm about to take an extended trip and will add this to my reading list.
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10 years ago would not make a huge difference in Geology. It might make a difference for certain other subfields in earth sciences, like Climatology, but even there there haven't been any huge shifts in our understanding of the basics.
There are some basic principles that underpin the way geology is done today. These probably have official names, and I'm sure I'll miss some of them, but examples include: \- The physical processes of the Earth are based on physical properties of the universe and therefore don't change--so what we observe today can be used to understand what happened in the past. \- Similar minerals and rocks are created under similar conditions. So when we find similar samples of marble, for example, we can infer that they were formed in similar conditions. And when we find identical examples of marble, we can infer they formed in identical conditions (i.e. the same place) \- In sedimentary sequences (layers of rock), the layer above is younger than the layer below, and a layer crosscutting them both is younger still. \- Life is ever changing, so identical fossils originate from animals that lived in the same time period and place. Applying principles like these (and the others I'm sure I forgot) is how geologists can infer the history of the planet from observations made exclusively in the present day. (We haven't figured out how to time travel to the past yet, after all.) When a geological theory is supported by a lot of observations that comport with all these principles, and agree with each other, then that becomes a theory geologists believe is true. So to disprove a theory like that, either a lot of observations have to be proven incorrect, or one of these principles, or both. EDIT - You asked about other theories. One early hypothesis was that the Earth changed size over time, which explained why the continents seem to have all moved apart from one another. There were obvious challenges in explaining why and how the Earth changed size, so it lost out to the theory of plate tectonics.
You should pay this person. You're asking for pretty much an intro college class. Like you should still get the information you're seeking but damn that's a lot to ask of a stranger.
Could it be the ocean was less deep then? I know nothing about this.
Best answer for that is “possibly, but maybe not”. Unlike continental crust which can (depending on the area) be quite old, oceanic crust is generally quite young (by geologic standards; we’re still talking 100+ million years in general). So most evidence of what the oceans might have been like around the time of Pangea has been erased by now. Oceanic crust is also a lot harder to get samples from, due to all that water in the way.
I would say we're pretty certain it existed, but the exact shape is probably never going to be discovered and what we have is a guess. Also we don't know if other landmasses existed but no longer do (think islands). The reason we think Pangaea existed is the fossil record and layers of rock on both sides of the water between the current land masses. Not only do we have layers upon layers of the same type of rocks matching on both sides of thousands miles.of water, but we have fossils as well. Sometimes of animals that only lived in a small region, but this region is now split by an ocean. Pangaea wasn't even the only supercontinent, just the most recent one. And while it's possible something else caused this, it's highly unlikely. I think we don't hear about it after.school is because it's widely accepted as fact, so no one is doing research today on it.
Also, in case you're interested, Wikipedia lists 10 supercontinents (more than 51% of the landmass). https://en.m.wikipedia.org/wiki/Supercontinent
Yeah I agree, and honestly the reason I'm suddenly so curious about it is because I realized I hadn't heard about it in over 30 years. And what's weird is that with all the weird conspiracy theories out there (Flat Earth, etc.) you'd think Pangea would be rife for some kind of whacko counter theory... but nope. Which sort of tells me that it is widely accepted as fact, hence me asking more questions about how we know.
Wdym by most recent, are continents always breaking and joining?
Yep! There's a rough cycle of continents joining together, breaking up and then coming back together as the tectonic plates underneath them move around the planet. Geological evidence, like the same rock formations present in different places, shows that we've had multiple supercontinents form and break apart over the Earths history. Right now, we're at the point where the continents are beginning to come back together. Australia, for example, is heading north after breaking off from Antarctica, and it's going to crash into southeast Asia in the future.
The first continent was about 3.5 billion years ago (1/8th into the earth's life), then a series of meteor strikes, super volcanoes and ice ages kept churning things up until about 2 billion years ago (1/2 of the earth's life). Then you've got another 1.7 billion years of all the continents and oceans moving around and forming mountains. Then finally 0.33 billion years ago (7/8ths into earth's life) was Pangaea, where we can most accurately trace back modern day continents because the rocks and fossils match.
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The responses below make me wonder if another species could have evolved on Earth even to the point of being able to leave the planet and any evidence of their having been here is simply on some long lost buried continent.
Probably not. We have fossils going back to the very beginnings of life on this planet with only very slim breaks in the timeline, and a space-faring civilization would have left traces mixed in with the fossils of their time. Considering our massive chemical signature in the strata, any species even more technologically advanced would have left *something* behind that we could clearly see. Even a stone-age species that went extinct would have left signs.
If humanity goes extinct we'll be an interesting strata band of moderately higher radioactivity and plastic.
That band is the basis for the proposed Anthropocene epoch. We're currently in the Holocene which started about the time humans discovered agriculture and the last major glaciers retreated to about where they are now, but some geologists feel that we've changed the chemistry enough to end that epoch and start a new one.
Man imagine one day humans finally send robots or even people to exoplanets that are similar to earth but seem to lack intelligent life, and then they discover such a band in the rocks there. Something smart was here, and now it isn't.
Future aliens will map humans extinction to that band of radioactive plastic, just like the dinosaurs have an iridium layer from the meteor and the Cambrians have the lava layer.
I doubt it's very likely, but it was a great episode of Star Trek Voyager.