Editing Amazon River (section)

== Geology ==
The Amazon River originated as a transcontinental river in the [[Miocene]] epoch between 11.8 million and 11.3 million years ago and took its present shape approximately 2.4 million years ago in the Early [[Pleistocene]].

The proto-Amazon during the [[Cretaceous]] flowed west, as part of a proto-Amazon-Congo river system, from the interior of present-day Africa when the continents were connected, forming western [[Gondwana]]. 80 million years ago, the two continents split. Fifteen million years ago, the main [[tectonic uplift]] phase of the Andean chain started. This tectonic movement is caused by the subduction of the [[Nazca Plate]] underneath the [[South American Plate]]. The rise of the Andes and the linkage of the Brazilian and [[Guayana Shield|Guyana]] bedrock shields,{{clarify|date=February 2017}} blocked the river and caused the Amazon Basin to become a vast inland sea. Gradually, this inland sea became a massive swampy, freshwater lake and the marine inhabitants adapted to life in freshwater.<ref>{{Cite web |url=https://rainforests.mongabay.com/amazon/ |title=The Amazon Rainforest |website=Mongabay |access-date=2020-02-09 |archive-url=https://web.archive.org/web/20190827231405/https://rainforests.mongabay.com/amazon/ |archive-date=27 August 2019 |url-status=live}}</ref>

Eleven to ten million years ago, waters worked through the [[sandstone]] from the west and the Amazon began to flow eastward, leading to the emergence of the Amazon rainforest. During [[glacial period]]s, sea levels dropped and the great Amazon lake rapidly drained and became a river, which would eventually become the disputed world's longest, draining the most extensive area of rainforest on the planet.<ref>{{cite journal |first1=J. |last1=Figueiredo |first2=C. |last2=Hoorn |first3=P. |last3=van der Ven |first4=E. |last4=Soares |title=Late Miocene onset of the Amazon River and the Amazon deep-sea fan: Evidence from the Foz do Amazonas Basin |journal=Geology |year=2009 |volume=37 |issue=7 |pages=619–22 |doi=10.1130/g25567a.1 |bibcode=2009Geo....37..619F |s2cid=70646688}}</ref>

Paralleling the Amazon River is a large aquifer, dubbed the [[Hamza River]], the discovery of which was made public in August 2011.<ref name="tv.ibtimes.com">{{cite web |url=http://tv.ibtimes.com/massive-river-found-flowing-beneath-the-amazon/1753.html |title=Massive River Found Flowing Beneath the Amazon |access-date=8 September 2011 |archive-url=https://archive.today/20111110171150/http://tv.ibtimes.com/massive-river-found-flowing-beneath-the-amazon/1753.html |archive-date=10 November 2011}}</ref>