Geoscientists find new fallout from 'the collision that changed the world'
By Liz Fuller-Wright, Princeton University
Neither the continents nor the oceans have always looked the way they do now. These “paleomaps” show how the continents and oceans appeared before (top) and during (bottom) “the collision that changed the world,” when the landmass that is now the Indian subcontinent rammed northward into Asia, closing the Tethys Sea and building the Himalayas. Global ocean levels were higher then, creating salty shallow seas (pale blue) that covered much of North Africa and parts of each of the continents. A team of Princeton researchers, using samples gathered at the three starred locations, created an unprecedented record of ocean nitrogen and oxygen levels from 70 million years ago through 30 million years ago that shows a major shift in ocean chemistry after the India-Asia collision. Another shift came 35 million years ago, when Antarctica began accumulating ice and global sea levels fell. Credit: Images created by Emma Kast, Princeton University, using paleogeographic reconstructions from Deep Time Maps, with their permission
When the landmass that is now the Indian subcontinent slammed into Asia about 50 million years ago, the collision changed the configuration of the continents, the landscape, global climate and more. Now a team of Princeton University scientists has identified one more effect: the oxygen in the world's oceans increased, altering the conditions for life.
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