Posted on 10/26/2021 6:19:34 AM PDT by Red Badger
We know that true polar wander (TPW) can occasionally tilt whole planets and moons relative to their axes, but it's not entirely clear just how often this has happened to Earth.
Now a new study presents evidence of one such tilting event that occurred around 84 million years ago – when dinosaurs still walked the Earth.
Researchers analyzed limestone samples from Italy, dating back to the Late Cretaceous period (100.5 to 65.5 million years ago), looking for evidence of shifts in the magnetic record that would point towards an occurrence of TPW.
Bacteria fossils trapped in the rock, forming chains of the mineral magnetite, offer some of the most convincing evidence yet of true polar wander in the Late Cretaceous – and it may help settle a scientific debate that's been going on for decades.
How true polar wander looks. (Victor C. Tsai/Wikimedia Commons/Public Domain)
"This observation represents the most recent large-scale TPW documented and challenges the notion that the spin axis has been largely stable over the past 100 million years," the researchers explain in their paper.
Earth is made up of a solid metal inner core and a liquid metal outer core, with a solid mantle and crust (the surface) moving slowly around on top of the liquid metal. Earth's magnetic field, generated by the outer core, is recorded in rocks like the ones studied here.
True polar wander is when the geographic poles shift substantially, so the outer wrapping of Earth tilts over. Nothing actually changes in terms of Earth's magnetic field, but the shifting rocks will record different paleomagnetic data as they move.
That data reveals the distance to the North and South geographic poles, enabling researchers to plot where these poles actually are. A fully vertical field means a rock was at the pole, while a fully horizontal field indicates it was at the equator.
"Imagine looking at Earth from space," says geologist Joe Kirschvink, from the Tokyo Institute of Technology in Japan. "True polar wander would look like the Earth tipping on its side, and what's actually happening is that the whole rocky shell of the planet – the solid mantle and crust – is rotating around the liquid outer core."
Part of the extraction work. (Ross Mitchell)
According to the study, there was around a 12 degree tilt on Earth around 84 million years ago, which was corrected relatively quickly – within about 5 million years, the equivalent of a "cosmic yo-yo" in the words of the researchers.
What that means is that these rocks – and Italy itself – took a journey towards the equator before tipping back.
The team says that previous studies hinting that true polar wander didn't happen during the Late Cretaceous simply didn't gather enough data from the geological record – something that can't be said about the latest research.
"That is one reason why it is so refreshing to see this study with its abundant and beautiful paleomagnetic data," says geophysicist Richard Gordon, from Rice University in Houston, who wasn't involved in the study.
The research has been published in Nature Communications.
Where did they come up with records for 84 million years ago?
Figured it out online probably & you just naturally know that everything you see online HAS to be true.
There is evidence that a new pole shift is imminent.............
The Cloud........................
I'll take door #3, Monty...
Yup.
And if you do a Google on Steen Mountain in eastern Oregon you will find out alot,
Consider how the Earth is a spinning ball in space and, not unlike a spinning tire, needs to be in balance or it will wobble. The more out of balance, the greater the wobbling will be.
The Earth’s balance is constantly changing as water is moved from the equator to the poles and its mass also changes as space junk hits the planet and becomes the planet.
If things become out of balance, what is to stop a spinning ball in space from seeking and regaining equilibrium and what would that look like if it ever happens?
I was about 10 or 11 when I read those ideas for the first time.
The idea that the Earth suddenly shifts to a new equilibrium point where the heavier poles move to a more equatorial place to re-balance the spin seemed and still seems totally plausible to me.
There have been a few new age-y kinda maps over the years that show or attempt to show what the new world will look like, how the current landscape changes, what’s above water, etc.
Some Bible passages also seem to describe such an event, but I’d have to find them, as I don’t remember which ones at the moment … I really should be working on something else now, but I am procrastinating, instead.
As unstable the land is in Italy they may want to double check theory.
The sane thing can be seen in the western part of the U.S..
Da plates move Larry
I’ve often wondered about the imbalances caused by huge amounts of trade goods being shipped all over the world....................
Oil fields and aquifers, too, are constantly being drained and changed to support new populations and new agriculture in order to feed and energize the world.
That’s a lot of mass slowly being redistributed. Does it matter? 🤷♂️ I dunno … just have to wait and see, I guess.
Maybe we’d see more earthquakes, volcanoes and similar events prior to something that major, too, but who knows.
It HAS to have some effect, collectively and additively over time..................
Not San Andreas’s Fault, it only became active ~20 million years ago.
I have irrefutable opinion that it was actually 84,500,000 years ago. These guys should try to be more precise when they those those big numbers around.
Yes, two actually outside and inside.
Touristas! (Echoed Il Donaldo!)Precisely!
And here north of the 30th, the winter Cold suppresses next hears fleas, ticks, and palmetto bugs! Also gives Apples the necessary cold degree days to allow spring blooming and next years apples!
(I have never seen a palmetto bug so it really works!!)
I have tipped over on my side before.
Oh btw, who was around 84 million years ago to record this stuff?
5.56mm
What if the asteroid that supposedly killed off the dinosaurs was what tipped the Earth over? Maybe it took 19 million years?........................
proving it is another thing...
You remind me of the Australian world maps which show their country at the top of the map. Of course the North Pole is at the top and east/west is on the sides. I also remember people mocking Sara Palin because she correctly pointed out that Alaska was close to Russia. The source of Tina Fey's idiotic SNL "joke" that people believe really happened. That's stoopid cuz the US is all the way on the other side of the world from Russia!
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