Creativity. Thought. Did a nickel famine trigger the 'Great Oxidation Event'? Washington, D.C.— The Earth's original atmosphere held very little oxygen. This began to change around 2.4 billion years ago when oxygen levels increased dramatically during what scientists call the "Great Oxidation Event. " The cause of this event has puzzled scientists, but researchers writing in Nature have found indications in ancient sedimentary rocks that it may have been linked to a drop in the level of dissolved nickel in seawater. "The Great Oxidation Event is what irreversibly changed surface environments on Earth and ultimately made advanced life possible," says research team member Dominic Papineau of the Carnegie Institution's Geophysical Laboratory. "It was a major turning point in the evolution of our planet, and we are getting closer to understanding how it occurred.
" Nickel exists in today's oceans in trace amounts, but was up to 400 times more abundant in the Earth's primordial oceans. What caused the drop in nickel? Article: Kurt O. 15 Free Guides That Really Teach You USEFUL Stuff. Advertisement Over the past months, we’ve written quite a few PDF manuals for you, on all kinds of diverging subjects, including BitTorrent, iTunes, iPhone, Twitter, Mac, Linux, Photoshop and several other topics.
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