How was the Grand Canyon created?

The Grand Canyon | Image: National Park Service

The Grand Canyon is undoubtedly one of the most stunning natural landmarks anywhere on our planet. But how did it form? Many people know that the Colorado River shaped this vast temple of rock, situated in Arizona, but where did all that water come from?

Scientists have two conflicting views. The first is the one that seems more obvious – the early Colorado extended simply by erosion, and gradually wound its way to the Colorado Plateau, where the Grand Canyon (click here for a virtual tour) is located. But in recent years a more controversial theory has arisen: that the Colorado was actually fed by a massive lake, Lake Bidahochi, which overspilled to form the Colorado.

There are several problems with this new theory – for a start, Lake Bidahochi no longer exists so scientists can only speculate its existence, with their evidence being remains of green sediment found around the area where they believe it used to be.The Grand Canyon | Image: National Park ServiceBut there is also evidence to support the Bidahochi argument: that same green sediment was found in the Grand Canyon as well, and it is more likely that this would have originated from a lake than from a sediment-carrying river.

Ultimately, it is not of immense importance to know how the Colorado River began, because we know that it was definitely this amazing river that shaped the Grand Canyon – indeed it is still shaping it today. But it’s still an interesting question, and one that is sure to get even more complicated as more research is done over the next few years.