Amazing Facts : Amazon River Once Flowed the Other Way
Millions of Years Ago, the Amazon River Flowed Backward – Here’s the Story
Do you know that the Amazon River used to flow in the direction opposite to what it does today — i.e., it used to flow towards the Pacific Ocean instead of the Atlantic? It may sound unbelievable but it really did happen. It ran west for millions of years. This is one of the most remarkable facts in the history of the Amazon River and the influence of geology on it.
The Ancient Flow of the Amazon
South America did not have the Andes Mountain range and looked very different around 100 million years ago. It also had river systems that fed the Pacific Ocean as it ran west. However, around 65 million years ago, the Nazca Plate began to push against South America, and the Andes began to form.
This newly formed mountain range acted as a barrier, and, with the river trapped on one side, the sediment and water began to form a massive inland basin which gave birth to the Amazon Basin. Over time, the river began the process of flowing in reverse, and it began to head towards the Atlantic Ocean.
How the Andes Changed Everything
The Andes Mountains did more than just cause the Amazon River to flow in a different direction; they changed continental life as well. The changed flow contributed to the development of the Amazon rainforest, one of the most diverse ecosystems in the world. The expanding Amazon Basin provided water and minerals to encourage the dense and luxuriant plant life.
Put another way, without the reversal of the Amazon River, the rainforest would not have come into existence.
Rocks That Tell the Story
One of the most fascinating twists in the story of the Amazon River arose from scientific analyses of geological materials. The Seabold and the ancient rock formations provided compelling evidence that the Amazon River did, at one point, flow in reverse. The evidence of prehistoric sea life and marine fossils found deep in the basin along with other continental fossils provide evidence that those regions were once part of joined territories with the Pacific.
Nature’s Slow Magic
This remarkable fact about the Amazon River illustrates that, with time, the processes of the Earth take place. New mountains appear, and old ones erode so that their materials provide the soil for entire forests, and rivers contour the land as they flow.
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