The Old Red Sandstone continent
Two continents weld together and shed red desert sediment across half the world.
- When
- Known to
- ± 10 million years
- Era
- Devonian, Paleozoic
The Caledonian collision joins Laurentia and Baltica into Euramerica, a landmass straddling the equator whose eroding mountains bury vast lowlands in red, iron-stained sand. These Old Red Sandstone deposits stretch from Canada through Britain to Scandinavia, and their river channels and floodplains preserve the fish and early tetrapods of the period. The name comes from the very first geological formations ever mapped systematically.