The Caledonian orogeny
Laurentia, Baltica and Avalonia collide, raising a mountain chain from Scandinavia to Appalachia.
- When
- —
- Duration
- 10 million years
- Known to
- ± 10 million years
- Era
- Silurian, Paleozoic
The closing of the Iapetus Ocean drives continental collision that builds a Himalayan-scale range, whose eroded remnants now form the Scottish Highlands, the Scandinavian mountains and part of the Appalachians. The suture runs through Britain, which is why Scotland's geology once belonged to North America and England's to a different continent. Sediment shed from these mountains fills basins across the northern hemisphere.