Thread: Collision of two continental plates weld them together?

When two continental plates collide, like say the Indian plate and the Euroasian plate, do they get welded together at the collision point? Have previously collided continental plates split apart again at the same "junction"? Or become a transform fault and the two plates start to slide as at the San Andreas transform fault?

the Iapetus ocean is a good example of an ocean that disappeared along a line from Newfoundland through Ireland and Scotland to Norway when Laurentia, Baltica and Avalonia collided

when the Atlantic ocean opened up, it followed more or less (but not quite) the old suture

Originally Posted by marnixR

the Iapetus ocean is a good example of an ocean that disappeared along a line from Newfoundland through Ireland and Scotland to Norway when Laurentia, Baltica and Avalonia collided

when the Atlantic ocean opened up, it followed more or less (but not quite) the old suture

Thanks marnixR. That link took me on a "trip" thru wikipedia, ending up at the Supercontinent Cycle: http://en.wikipedia.org/wiki/Wilson_cycle

although calling it a cycle with 2 known supercontinents (+ beyond 1 billion years things get a bit too fuzzy to be sure) is maybe a bit overgenerous :wink:

Originally Posted by marnixR

although calling it a cycle with 2 known supercontinents (+ beyond 1 billion years things get a bit too fuzzy to be sure) is maybe a bit overgenerous :wink:

Yes - there are no citations in the article for the earlier supercontinents. Here's a summary from the wiki article:

- Pangaea, formed about 300 million years ago.
- Pannotia, formed about 600 million years ago.
- Gondwanaland
- Rodinia, existed ~1.1 billion to ~750 million years ago
- Pannotia
- Columbia: ~1.8 to 1.5 billion years ago.
- Kenorland: ~2.7 to ~2.1 billion years ago.
- Ur (existed ~3 billion years ago)
- Vaalbara (~3.6 to ~2.8 billion years ago).