75 books
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8 voters
Astrophysics
“
Like the Great Oxidation Event, the Great Unconformity injected an enormous quantity of oxygen into the atmosphere through a massive and efficient subduction of organic carbon into Earth's mantle. When this event occurred, the oxygen quantity in Earth's atmosphere jumped from 1% or less up to 8%. Just before the time of the Cambrian explosion 543 million years ago, another major continental erosion event coupled with oceanic sediment subduction led to a jump in the atmosphere oxygen level from 8
...more
”
― Designed to the Core
― Designed to the Core
“
People who believe they are ignorant of nothing have neither looked for, nor stumbled upon, the boundary between what is known and unknown in the universe.
”
― Astrophysics for People in a Hurry
― Astrophysics for People in a Hurry
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