Scientists discover Amazon river is 11 million years old

July 29, 2009,
Amazon river
Satellite image of mouths of Amazon river in Brazil. Image: Wikimedia Commons

Researchers at the University of Liverpool have discovered that the Amazon river, and its transcontinental drainage, is around 11 million years old and took its present shape about 2.4 million years ago.

University of Liverpool researchers, in collaboration with the University of Amsterdam and Petrobras, the national oil company of Brazil, analysed sedimentary material taken from two boreholes near the mouth of the river to calculate the age of the Amazon river and the Amazon deep sea fan.

Prior to this study the exact age of the Amazon, one of the two largest rivers in the world, was not known. Until recently the Amazon Fan, a submarine sediment column around 10km thick, had proven difficult to penetrate. New exploration efforts by Petrobas, however, have lea to two new boreholes being drilled near the mouth of the Amazon - one 2.5miles (4.5km) below sea level - which resulted in new sedimentological and paleontological analysis of samples from the river sediment.

"River records provide a unique insight into the palaeoclimate and geography of the hinterland," said Jorge Figueiredo from the University's Department of and Sciences

"This new research has large implications for our understanding of South American paleogeography and the evolution of in Amazonia and on the Atlantic coast. The origin of the is a defining moment: a new ecosystem came into being at the same time as the uplifting Andes formed a geographic divide."

The study was published in the scientific journal, Geology, in July 2009.

Source: University of Liverpool (news : web)

Explore further: The Amazon River is 11 million years old

Related Stories

The Amazon River is 11 million years old

July 7, 2009

The Amazon River originated as a transcontinental river around 11 million years ago and took its present shape approximately 2.4 million years ago. These are the most significant results of a study on two boreholes drilled ...

Amazon River Once Flowed in Opposite Direction

October 24, 2006

The world's largest river basin, the Amazon, once flowed from the Atlantic Ocean to the Pacific - opposite its present direction - according to research by a geology graduate student and his advisor at the University of North ...

Earth's crust pulsates in the Amazon basin

September 17, 2005

Earth's crust pulsates up and down in the center of the Amazon basin, new research suggests, according to researchers in Brazil and United States.

Amazonian amphibian diversity traced to Andes

March 10, 2009

Colorful poison frogs in the Amazon owe their great diversity to ancestors that leapt into the region from the Andes Mountains several times during the last 10 million years, a new study from The University of Texas at Austin ...

Recommended for you

How the Elwha dam removals changed the river's mouth

January 19, 2018

For decades, resource managers agreed that removing the two dams on the Elwha River would be a big win for the watershed as a whole and, in particular, for its anadromous trout and salmon. The dams sat on the river for more ...

Glacial moulin formation triggered by rapid lake drainage

January 18, 2018

Scientists are uncovering the mystery of how, where and when important glacial features called moulins form on the Greenland Ice Sheet. Moulins, vertical conduits that penetrate through the half-mile-deep ice, efficiently ...


Adjust slider to filter visible comments by rank

Display comments: newest first

not rated yet Jul 29, 2009
I wonder if any human(oid) remains can be found amongst all that sediment where ancient peat 'bogs' formed. With all the vegetation so assist the formation of peat, and the river to attract all forms of animal life, some evidence should remain and could be as valuable, and as old, as that found in Africa in the last decade.
5 / 5 (2) Jul 29, 2009
Humans hadn't migrated to the West until about 20,000 - 30,000 years ago.

3 / 5 (1) Jul 30, 2009
Was this not on physorg before? Im quite sure..
4 / 5 (1) Jul 30, 2009
And yet another story (2006) states uncategorically that "Amazon River Once Flowed in Opposite Direction" during a period "between 65 million and 145 million years ago."

Science journalism doesn't do anyone a favor when it treats hypotheses as FACT. Failing to address such contradictions within 'news' only serves to confuse, discourage, and skeptify the public about science.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.