The Amazon started to form over
200 million years ago when its highlands were formed on Gondwanaland, daughter of Pangea.
The Amazon River, newly formed, flowed west to the Pacific as there was no barrier to stop
it.
140 million years
ago, Gondwanaland split apart and South America was left adrift. When the South American
plate collided into the Nazca plate, the impact crushed the young rocks of Southern
America to form the Andes. This fresh mountain range blocked off the former mouth of the
Amazon River, creating a huge fresh water lake.
Over the next 50 million years,
the continent began to tilt. Eventually, this caused the freshwater lake to burst through
its stony barriers and form the Amazon River Basin. |