The oldest river in the world ran through Pangea
Rivers are poor archivists of their own past.
They don’t sit still like fossils, or record a single birthdate like volcanic rock. Instead, they wander across floodplains, cut into rock and often move around or even abandon their channels. A river can spend millions of years destroying the very evidence that would prove how long it’s been there.
That makes the question of the world’s oldest river surprisingly difficult. When geologists ask which river is the oldest on Earth, they’re not looking for one ancient thread of water has flowed unchanged since deep time. Rather, they’re looking for local persistence: a drainage corridor that has survived mountain-building, climate upheaval and continental rearrangement while continuing to carry water across the same broad landscape.
It really is tough work.
But geologists are hard workers, and have mapped several candidates. By that standard, the Finke River of central Australia, known to Indigenous people as Larapinta, has become the leading candidate, believed to be a whopping 400 million years old. This is over 150 million years before the dinosaurs appeared. But it’s not the only candidate. [Continue reading…]