A piece of North America got stuck onto Australia 1.6 billion years ago

[lpetrich]

1.7-Billion-Year-Old Chunk of North America Found Sticking to Australia

Geologists matching rocks from opposite sides of the globe have found that part of Australia was once attached to North America 1.7 billion years ago.

Researchers from Curtin University in Australia examined rocks from the Georgetown region of northern Queensland. The rocks — sandstone sedimentary rocks that formed in a shallow sea — had signatures that were unknownin Australia but strongly resembled rocks that can be seen in present-day Canada.

The researchers, who described their findings online Jan. 17 in the journal Geology, concluded that the Georgetown area broke away from North America 1.7 billion years ago. Then, 100 million years later, this landmass collided with what is now northern Australia, at the Mount Isa region.

That journal article: Laurentian crust in northeast Australia: Implications for the assembly of the supercontinent Nuna | Geology | GeoScienceWorld. Nuna, also called Columbia, then broke apart 300 million years later, around 1.3 billion years ago.

The best-known supercontinent is Pangaea. It formed around 335 million years ago and it started breaking apart around 175 million years ago. It was roughly Australia - Antarctica - India - Arabia - Africa - South America - North America - Greenland Eurasia. Here's what Pangea looks like mapped with modern political borders

Before that was Rodinia. It formed around 1.3 - 0.9 billion years ago and it broke up around 750 - 633 million years ago. Most of its former continents were clustered around North America, but details are not very clear. For instance, Australia was stuck onto western North America, but it is not very clear where it was.

I've encountered discussion of possible older supercontinents, like Kenorland, Ur, and Vaalbara, but it's hard to find much on them, and they are much smaller than the later supercontinents. Vaalbara existed some 3 billion years ago, and it was composed of eastern South Africa and northwestern Australia -- not very large.

 

[Jokodo]

The best-known supercontinent is Pangaea. It formed around 335 million years ago and it started breaking apart around 175 million years ago. It was roughly Australia - Antarctica - India - Arabia - Africa - South America - North America - Greenland Eurasia. Here's what Pangea looks like mapped with modern political borders

I believe that map might be somewhat inaccurate in including all of Mesoamerica and the US Pacific coast as part of Pangea - aren't those areas that didn't exist (as part of a continental plate) back then but mostly formed through accretion and the scooping up of various islands?

 

[humbleman]

The best-known supercontinent is Pangaea. It formed around 335 million years ago and it started breaking apart around 175 million years ago. It was roughly Australia - Antarctica - India - Arabia - Africa - South America - North America - Greenland Eurasia. Here's what Pangea looks like mapped with modern political borders

I believe that map might be somewhat inaccurate in including all of Mesoamerica and the US Pacific coast as part of Pangea - aren't those areas that didn't exist (as part of a continental plate) back then but mostly formed through accretion and the scooping up of various islands?

Actually I think you have a good point.

 

[lpetrich]

The best-known supercontinent is Pangaea. It formed around 335 million years ago and it started breaking apart around 175 million years ago. It was roughly Australia - Antarctica - India - Arabia - Africa - South America - North America - Greenland Eurasia. Here's what Pangea looks like mapped with modern political borders

I believe that map might be somewhat inaccurate in including all of Mesoamerica and the US Pacific coast as part of Pangea - aren't those areas that didn't exist (as part of a continental plate) back then but mostly formed through accretion and the scooping up of various islands?

That's right.

The maps that show that in the most detail are Ron Blakey's, at Deep Time Maps™ – maps of ancient Earth. They show present-day political boundaries atop their reconstructions, and you can watch North America's west coast grow over time. Back in the Permian, British Columbia, western Washington and Oregon, most of California, and western Mexico did not exist in their present form -- they were still island arcs, though some of them were starting to get accreted.

 

[Tigers!]

How much to return it to you? We are finished with it.

 

[Kharakov]

When did Crete accrete?

 

[bilby]

I am ... con-tam-in-ated.