Found the cause of the Amazon River instead of flow

The Amazon River once flowed in the opposite direction, from east to west.The reversal of the world's largest river on Earth is not trivial, and geologists have contemplated the cause of this incident for a very long time.

In a recently published study, Dr. Victor Sacek of the Sao Paulo University (Brazil) demonstrated that erosion is the cause of this great change.

The western part of the continent is held by the majestic Andes mountains, so it seems reasonable that this largest river in South America flows east. The Amazon River emits five times more water every year than any other river in the world.

However, 10 million years ago, most of the area known as the Amazon River Basin is now drained by a river that flows westward into a giant lake located at the foot of the northern mountains of the Andes. From there, the water flows to the North towards the Caribbean Sea. Until the Isthmus of Panama was not yet formed, this water was then moved westward into the Pacific Ocean.

In order to tilt the whole continent and change the direction of a river, there should be a wide range of dynamics such as the change of convection in the earth's crust, created by the disintegration of Africa and South America.

Sacek, on the other hand, points out that the rise of the Andes as well as the South America's geological rise to the Nazca Plate could explain the process in proper dates. Sacek also raises the fact that when the mountain range grows it will block rain clouds, thus causing more erosion.

Rainforest, the Amazon basin accounts for one third of South America

At first the rise of the Andes created a geological trench in the East, forming a large lake that emptied the west of the Amazon. However, over time, the depth of the lake is reduced as the Andes Mountains stop high and the level of erosion increases, leading to the lake being replaced by a series of wetlands called Pebas . At that time the vast Pebas swamp did not have the ecosystem as we see it today, but the accumulation of sediment lifted the area to such an extent that the amount of rain in the area was pushed back in one direction. other.

This model fits perfectly with the observation that the deposited sediment in Amazon's mouth has increased during its flow toward the east. At first, when the Amazon upstream was relatively flat, the sediments were dumped away from the river mouth.

However, Sacek acknowledged that his model "could not fully reproduce the development of space and time of the Pebas system as observed in geological data" and further research was needed.