Quote: “Both Snowball Earth periods had extreme impacts on the development of life. It helps us understand the evolution of Earth and Earth’s atmosphere, and evolution of life, for that matter.” -Kevin Chamberlain, a UW research professor in the Department of Geology and Geophysics.
Initial Claim: Professor Chamberlain’s extensive research about the rise of life’s correlation to a Snowball Earth shows evidence that the Great Oxidation Event occurred approximately 2.5bya. His research talks about when the Earth’s climate swung where the polar ice caps extended to the equator and the Earth was a complete snowball, and the atmosphere was separated from the hydrosphere. His paper then states that when the Snowball Earth melted and turned slush, Great Oxygenation Event occurred, giving way to aerobic life.
Background: The first Snowball earth period occurred 2.3bya, where, at that time, the earth’s atmosphere was mostly made up of greenhouse gasses such as methane and carbon dioxide, but as the levels of oxygen began to rise, the levels of these greenhouse gasses dropped dramatically, which led way to the Great Oxidation Event (where the methane was oxidized). The Great Oxidation Event, in this scenario, occurred directly after the first snowball earth turned into a slushball and eventually solid land.
Example 1: My first piece of evidence to prove the correlation between the Snowball Earth and the Great Oxidation Events is drawn from a Professor of Geology at Lund University in Sweden, Ulf Söderlund. Professor Söderlund draws the results of his research from the dating of volcanic rocks excavated in what is now South Africa, which proved that the Snowball Earth that had originally been thought to have taken place 2.2bya, to 2.4bya, which is immediately after the first snowball earth. This might seem like a miniscule amount of time, but the change of 200 million years shows a direct correlation with The Great Oxidation Event.
Using this evidence, we can connect the Snowball Earth to the emergence of oxygen, and that it took place at a time when the vast majority Earth's landmasses were gathered in a supercontinent, known as Kenorland. Kenorland was not only located right on the equator, but it also had extreme volcanic activity taking place constantly, which made the atmosphere extremely unstable. To further back up this point, Lund tested volcanic rocks from Kenorland to prove the timing of his claims.
http://olympics.wikibruce.com/images/c/c9/Map-kenorland.gif
Example 2: A separate example that backs up Lund’s scenario is the latest occurrence of a global glaciation event, that took place approximately 600 million years ago. This event was also immediately followed by a significant increase in the Earth’s oxygen content. This event does not necessarily prove that the melting of Snowball Earths led to the rise of oxygen, but it does help enforce Lund’s research about the correlation between the two.
Conclusion: The conclusion to be drawn from Professor Söderlund and Lund University’s research is more than just the timing of these events, though. It suggests that the Rise of Oxygen via a singular Great Oxygen Event happened in direct correlation to the melting of the first snowball earth 2.4bya.
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