Skip to comments.Large meteorite impacts drove plate-tectonic processes on the early Earth
Posted on 10/12/2017 1:03:40 PM PDT by JimSEA
An international study led by researchers at Macquarie University has uncovered the ways in which giant meteorite impacts may have helped to kick-start our planet's global tectonic processes and magnetic field. The study, being published in the premier journal Nature Geoscience, explores the effect of meteorite bombardment, in geodynamic simulations of the early Earth.
Our results indicate that giant meteorite impacts in the past could have triggered events where the solid outer section of the Earth sinks into the deeper mantle at ocean trenches a process known as subduction. This would have effectively recycled large portions of the Earth's surface, drastically changing the geography of the planet," explained lead author Associate Professor Craig O'Neill from Macquarie University
Read more at: https://phys.org/news/2017-09-large-meteorite-impacts-drove-plate-tectonic.html#jCp
(Excerpt) Read more at phys.org ...
I have a theory that meteor collision(s) started the outer crust spinning at a slightly different speed than the inner core, which gives us our magnetic field.
And the ‘springy’ action as it oscillates back and forth gives us the CHANGING magnetic field
Mars might have had the same conditions, but after friction caused the oscillations to die away (like a swinging door slows and stops), the magnetic field went away and the solar winds evaporated all the water off the surface.
If earth isn’t flat, why are there “plates”? Do you see any plates on a spherical orange? No, you only have those damn plates on the flat table.
It still is...
My theory would also explain the seeming lack of history past 10 or 12 thousand ears ago (current oscillation periodicity)
With seemingly abundant evidence of entire civilizations from 65000 to a million years ago
If the core of the Earth is sufficiently massive, it would rotate at its own speed. Inertia would be enough to explain the outer mantle and crust turning at a different speed. Similarly, the poles would try to turn slightly faster than the equator causing plate tectonics through Coriolis forces. Observing the rotational behavior of the sun and Jupiter is proof that such a thing is possible, at least insofar as the outside of a planet is concerned. The core of the Earth is composed of iron and some heavy elements and is very dense. The magma above is hot and somewhat fluid providing lubrication between the solid crust and the core, and allowing them to rotate at different speeds.
From what I understand a lot of water is required for plate tectonics.
I have a theory. Plate tutonics cause global warming.
Hey, don’t laugh. It’s as valid as “fossil “ fuels cause globull warming.
All our geology depends on water and there is certainly a lot in the mantle, some in minerals there and brought down by plate subduction and minerals in the plate. Volcanoes gave us our atmosphere and much water. They are very much tied to plate subduction and the water brought down.
When the Sudbury event happened, I read there was a large chunk of the NA plate that was actually flipped over, just like a pancake!
It’s not surprising.
I’ve also read that the size of the Sudbury meteor (asteroid??) was something like 6 miles wide, and it came almost directly in.
Can you say Boom!!!???
Note: this topic is from 10/12/2017. Thanks JimSEA.
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