Why is the World's Land Mass mostly in the North?

[Carrot Flower King]

There's this thing called plate tectonics. Mebbe the OP has heard of it.

There's this science called geology, which shows that continents/land masses have been in different parts of the Earth's surface at different times in the past.

If only there were means of finding this out...

 

[Vixen]

Centrifugal force. The dense, heavy basaltic rocks of the sea floor are thrown outwards towards the rim, so the lighter rocks of the continental land masses float in towards the centre.

Centrifugal force from the earth's spin? I don't see how heavier rocks are thrown further outwards than the lighter ones? Do the continents float?

 

[Vixen]

Also don't see why oceans should define continents. Ignore the oceans, and the concept of land mass, and things look different. Continents are each surrounded by other continents. "Landmass" is an artifact of water filling the low spots.

I can't picture this, either, as this would suggest the larger landmasses, such as Eurasia, which includes some of the world's highest points (Everest, Andorra, etc) was just a case of their being higher out of the ocean/sea. Yet the highest continent of all - Antarctica - is in the South. It is also the driest and windiest, so likely just a rocky desert underneath its one-mile thick ice cover. Yet this is where the South Pole lies, directly opposite the North Pole, which has no land mass. The oceans in that region are also particularly rough and deep - hence why a search for the missing aeroplane was such a problem in this region, with much of the deep ocean beds never explored (I imagine upside down deep mountainous crevases).

So I think maybe it is to do with the tilt of the earth on its axis as it spins, with the pull of the moon on the tides causing the southernmost regions to have more water coverage and thus less land mass in view.

 

[Vixen]

There's this thing called plate tectonics. Mebbe the OP has heard of it.

There's this science called geology, which shows that continents/land masses have been in different parts of the Earth's surface at different times in the past.

If only there were means of finding this out...

Are you claiming there are fewer or more plate tectonics in the north than in the south? How do you account for the VOLCANOs in Antarctica?

 

[Vixen]

A brief history of the land masses by Map Men:
https://www.youtube.com/watch?v=Nlzehe4mta4

And why it occurs.
And where we'll be in 250million years. Maybe.

That's looks intuitively probable, given that the silhouette of South America seems to fit that of the West Coast of Africa like a jigsaw. It is likely there has been continental drift but the prediction of 'what it will look like in 250 million years' is just one person's hypothesis.

It also buys into the idea that if all the land mass once fit together like a jigsaw puzzle then it becomes apparent where the idea of a 'missing continent' comes from [Atlantis] as there appears to be one jigsaw missing in that spot.

 

[lomiller]

they are now. I'm not familiar enough with archaeology to know if this always was the case, for all we know it's just coincidence?

IMO coincidence is the wrong word here. The continents must be distributed 1 of 3 ways, balanced, more in the north more in the south. No matter which it was you could ask the same question.

 

[lomiller]

Related question, and food for CTs: Do you think Global Warming is having an effect on the thickness of the earth's crust?

I'm not sure how it's related but the answer is that global warming is having a very slight impact on the thickness of the earths crust. The oceans are part of the crust and thermal expansion has increased sea levels a little over 10cm so far. This is due to expansion of water already there, not new water flowing in from somewhere else so on average global warming has made the earths crust a little over 7cm thicker.

 

[casebro]

I'm not sure how it's related but the answer is that global warming is having a very slight impact on the thickness of the earths crust. The oceans are part of the crust and thermal expansion has increased sea levels a little over 10cm so far. This is due to expansion of water already there, not new water flowing in from somewhere else so on average global warming has made the earths crust a little over 7cm thicker.

a) so melted glaciers have made only an insignificant contribution to sea rise?

b) I was mostly tongue in cheek, but my idea was that the warmer atmosphere would not absorb as much heat form the crust, so the lower layer of crust might melt into the magma. I don't think most people count water as crust. So if we exclude the thermal expansion of the water, how is the crust these days? You know, the hard layer that holds the oceans up?

 

[casebro]

Ignoring the oceans, the water will run to the low spots no matter where the axis is. Think of a globe with the lumps and bumps and off-balancedeness of Earth. Make it like a top- wrap a string around it and give it a toss. Watch as it vibrates and wobbles and finally settles on one axis. Which MUST* be exactly where we are now.

* Physics, dude.

eta: Most tops are also top heavy, conically in fact. No joke.

 

[casebro]

Perhaps The Black Hole of Calcutta is where the string was inserted?

 

[casebro]

Short answer: Because it is the most stable axis point.

Billions of years for wobbles to settle to here.

 

[RecoveringYuppy]

I said smoother as I thought the world not round becaise spinning, so oblate but smooth.

No, the Earth is round. The difference due to the oblateness due to spinning that you refer to is on 3 tenths of 1 percent. That's still round.

But the Earth is not smooth because there are places where the terrain changes abruptly.

There is a meme that says the Earth is smoother than a billiard ball. That meme is wrong. The Earth is rounder than a hypothetical billiard ball that barely meets regulation. But it's not clear that any billiard balls are as out of round as the regulations might allow. It's also certain that the Earth has discontinuities that are less smooth than most billiard balls.

 

[Lukraak_Sisser]

IMO coincidence is the wrong word here. The continents must be distributed 1 of 3 ways, balanced, more in the north more in the south. No matter which it was you could ask the same question.

I meant it was coincidence they were more in the north at this moment in time.

 

[rjh01]

a) so melted glaciers have made only an insignificant contribution to sea rise?
<snip>

That was not what he was saying. Glaciers melting would have an additional contribution to sea-level rise. However, we can disregard melting glaciers as all what they are is water moving from one place on the crust to another with a slight decrease in total volume (liquid water has less volume than ice).

As to the question in the title, my answer is that throughout most of history the majority of the world's land mass is in either the Northern or Southern hemispheres. Some of the time most of the landmass would be in only one hemisphere. It would therefore be most unlikely that humans evolved just when the landmasses were half-way though the move from one hemisphere to the other.

 

[Samson]

I'm not sure how it's related but the answer is that global warming is having a very slight impact on the thickness of the earths crust. The oceans are part of the crust and thermal expansion has increased sea levels a little over 10cm so far. This is due to expansion of water already there, not new water flowing in from somewhere else so on average global warming has made the earths crust a little over 7cm thicker.

Yes sounds right the average ocean depth is 3800 meters, same depth as Titanic and MH370 foundered.

 

[SpuriusMaximus]

No, the Earth is round. The difference due to the oblateness due to spinning that you refer to is on 3 tenths of 1 percent. That's still round.

But the Earth is not smooth because there are places where the terrain changes abruptly.

There is a meme that says the Earth is smoother than a billiard ball. That meme is wrong. The Earth is rounder than a hypothetical billiard ball that barely meets regulation.

As I've pointed out in message #36, at the scale of a 57mm billiard ball, Mt Everest would be a 40 micron imperfection.

A regulation pool ball must not have imperfections of more then +/- 0.005 inches, which means 127 microns. That's over 3 times bigger.

So, no, we're not talking about "barely meeting regulation". It's WAY smoother than regulation allows.

So, you know, do the maths before proclaiming which memes are wrong and which aren't.

But it's not clear that any billiard balls are as out of round as the regulations might allow.

"It's not clear" isn't much of an argument premise. Either you know something to be true or false, or you can't use it as a premise.

It's also certain that the Earth has discontinuities that are less smooth than most billiard balls.

Source?

 

[Matthew Best]

Why is the World's Land Mass mostly in the North?

Saves time, shoe leather.

 

[Carrot Flower King]

Are you claiming there are fewer or more plate tectonics in the north than in the south? How do you account for the VOLCANOs in Antarctica?

How on earth do you manage to get that from my post? Pretty much all of what is now northern hemisphere has been southern hemisphere at one time or another. Why would there NOT be volcanos in Antarctica?

What I said was that there is a whole load of pre-existing science about the subject. One could go and read many, many geological texts or look at many, many geological websites which contain much information about plate tectonics, movements of the Earth's crust and where the different plates have been over time.

None of this is new or secret, hidden only on vaults open to the initiates on the second Sunday after Lent if you know the handshake and password. It is readily available to any and all.

I do not understand the point of your original question in light of the above.

 

[Carrot Flower King]

Do the continents float?

Seriously, go read some basic geology first to get an understanding of the structure of the planet.

 

[Carrot Flower King]

That's looks intuitively probable, given that the silhouette of South America seems to fit that of the West Coast of Africa like a jigsaw. It is likely there has been continental drift but the prediction of 'what it will look like in 250 million years' is just one person's hypothesis.

It also buys into the idea that if all the land mass once fit together like a jigsaw puzzle then it becomes apparent where the idea of a 'missing continent' comes from [Atlantis] as there appears to be one jigsaw missing in that spot.

I don't even know where to begin with this one...

There is more to the idea of South America fitting against West Africa than just the visuals on a map. Wegener may have started off with that, but he didn't have the data subsequently acquired, which gives much more information.

The "missing continent" and "Atlantis" bit is purest nonsense, given the hundreds of millions of years involved, long before primates evolved and there being no possible way humans could have known that until the recent geological modelling. "Missing" in and of itself is pretty nonsensical anyway.

Really, have you ever looked at some basic geology?