I don't understand plate tectonics, if this is how the plates

>>8250477
>how do the continents drift so far while still retaining their shape?

protip: they don't retain their shape

They don't retain their shape, the edges of plates push up or over each other all the time, this is how most large mountain ranges are formed (Andes, Himalayas). In other places the plates are splitting apart and new land is being created there, most of this is under the oceans but places like Iceland and the African Rift Valley show this on land.

>>8250477
https://upload.wikimedia.org/wikipedia/commons/8/8c/Continental_Drift_(740_million-to-Today).gif

Here you go, it was too big to upload on here.

>>8250477
Fun fact: Australia just had to update all their coordinates because Continental drift has made the old ones inaccurate.

http://www.bbc.co.uk/news/technology-36912700

>Australia is to shift its longitude and latitude to address a gap between local co-ordinates and those from global navigation satellite systems (GNSS).

>Local co-ordinates, used to produce maps and measurements, and global ones differ by more than 1m.

>>8250480
forgot "you can't". this essential to the meme

>>8250477
the planet grows. everything fits on a smaller globe. visualize inflating a balloon in an egg while retaining its shell fragments as it breaks up.

>>8250480
So does the east coast of south America fitting perfectly into the west coast of Africa just a coincidence? I understand it isn't exactly the same, but the difference doesn't seem proportional.
>>8250489
>>8251317
>>8251357
Thanks

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>>8251553
ocean floor map

>>8251553
The two edges of those continents simply don't have much changing their shape, all they are doing is slowly moving further apart. It's not like the Indian Plate shoving itself up into the Eurasian Plate and making the Himalayas.

can someone on /sci/ help me out, in aprevious geology thread one geo anon said something about a period in geology that is still a mystery to this day, like we know very little of it, can anyone help me out in listing said period of itme?

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>>8254125
Generally, the farther back in time you go, the less information we have, since the oldest rocks are likelier to be either buried or eroded long ago. It was probably the Pre-cambrian era.

>>8254389
thx m8 i appreciate your help

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Geology student. A seminar I attended last year was bout trying to use sediment sample data from the Andes mountains to uncover how much compression the western edge of South America has undergone since compression began about 20 million years ago (This data is very well known in the western US because of decades of research but isn't well studied in South America).

Best estimate from his research is that it has compressed by 2x. Meaning, from the eastern edge of the Andes to the ocean would have been two times wider if you saw it 20 million years ago.

>>8254125
Again, me. The Hadean. We know nothing of the Hadean because Earth was molten at the time and all records have been obliterated. All the data from the Hadean we've gleaned from meteors.

>>8251357
This is complete garbage

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>>8250477
There's basically two types of crust: dense oceanic crust and less dense continental crust. Oceanic crust is much more dense, so when the two types collide (called convergence), the denser oceanic crust subducts beneath the continental crust. This makes the kind of volcanoes and earthquakes you see around the Pacific.

The main reason these plates collide is because of mid-ocean ridges, which are big lines where magma comes up from below and creates new crust, shoving the older crust away from the mid-ocean ridge. This means tectonic plates are spreading apart (divergence). This happened between what is now Africa and S America in the past, and the line where they separated is now in the middle of the Atlantic ocean. This causes volcanoes, but not earthquakes. It's why Iceland has lots of geothermal activity, the Atlantic ocean rift runs right through the island and is slowly ripping it apart.

When you have two continental crusts colliding, since they are both not very dense, they just kinda crumple up. Thats what happened when India ran into Asia. The north end of the Indian continent folded up into the Himalayas mountains.

So basically, continental plates don't change much at the large scale except at the edges, because they're always colliding with each other, unless a ridge forms in the middle and rips it apart (like what's tearing Baja California away from N America)