3 billion-year-old Earth had water everywhere, but not one continent, study suggests

rod

Oct 22, 2019
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Chemicals in ancient ocean rocks hint that 3.2 billion years ago, the surface of a baby Earth was continent-free and covered by a global ocean.

3 billion-year-old Earth had water everywhere, but not one continent, study suggests : Read more
"We can't really say what the source of the water is from our work, but we do suggest that whatever the source, it was present when the magma ocean was still around," Johnson told Live Science in an email."

Explaining the origin of Earth's abundant water supply using collisions and the Faint Young sun problem is always interesting. 3.2E+9 years ago, the Earth was still deep in the Faint Young Sun. 4.5E+9 years ago or perhaps a bit later, the Earth was likely suffering the synestia phase of matter, something the new computer models show for giant impacts taking place near the late stage of planetary evolution. https://phys.org/news/2019-09-planetary-collisions-internal-pressures-planets.html ""We have no direct observations of the growth of Earth-like planets. It turns out that the physical properties of a planet can vary wildly during their growth by collisions. "

My observation, there is no direct observation of how Earth has so much abundant water today for life either.
 
Oct 21, 2019
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Chemicals in ancient ocean rocks hint that 3.2 billion years ago, the surface of a baby Earth was continent-free and covered by a global ocean.

3 billion-year-old Earth had water everywhere, but not one continent, study suggests : Read more
The article says "They found that 3.2 billion years ago, oceans held more oxygen-18 than oxygen-16 (the latter is more common in the modern ocean) " I think that statement as it stands is grossly incorrect. The current natural abundance of oxygen-18 as a proportion of the oxygen found on Earth is only 0.2%, the statement implies that 3.2 billion years ago there was more than 50% abundance! What I think the article means to say is that 3.2 billion years ago the small fraction of oxygen-18 that comprised the total oxygen in the ocean was a larger value than that of the modern ocean. :)
 

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