Posted on 07/15/2019 9:21:19 AM PDT by SunkenCiv
An ancient tree that contains a record of a reversal of Earth's magnetic field has been discovered in New Zealand. The tree -- an Agathis australis, better known as its MÇori name kauri -- was found in Ngawha, on New Zealand's North Island, during excavation work for the expansion of a geothermal power plant, stuff.nz reports.
The tree, which had been buried in 26 feet of soil, measures eight feet in diameter and 65 feet in length. Carbon dating revealed it lived for 1,500 years, between 41,000 and 42,500 years ago...
The lifespan of the kauri tree covers a point in Earth's history when the magnetic field almost reversed. At this time, the magnetic north and south went on an excursion but did not quite complete a full reversal.
Earth's magnetic field is thought to be generated by the iron in the planet's core. As it moves around, it produces electric currents that extend far into space. The magnetic field acts as a barrier, protecting Earth from the solar wind. This is a stream of charged particles from the Sun that could strip away the ozone layer if it were to impact the atmosphere.
When the magnetic field reverses -- or attempts to -- it gets weaker, leading to more radiation from the Sun getting through. Previously, scientists have linked extinction events to magnetic field reversals.
The newly discovered kauri tree's rings contain a complete record of a near-reversal -- the first time a tree that lived during the entire event has ever been found. "It's the time it takes for this movement to occur that is the critical thing...We will map these changes much more accurately using the tree rings," Hogg told stuff.nz.
(Excerpt) Read more at newsweek.com ...
I remember back in 1968 or 69, SAGA magazine had an article on how the poles would reverse, allowing the crust of the earth to slide around, destroying cities.
Then when the magnetic field reestablished itself, the crust would be stable, but you would not know where on the earth you would end up.
There was a great illustration of skyscrapers falling as everything collapsed.
I kept that article for years because of the illustration. Wish I still had it.
If they didn't, everyone would be stumped.
Roosters would crow. Dogs would bark.
Earth’s Magnetic Field Flipped Superfast
Author: Alexandra Witze, Science News
September 2, 2010
https://www.wired.com/2010/09/superfast-magnetic-reversal/
What did the birds do when the magnetic field switch last time?....................
That's not what they are doing here. Notice it doesn't say that the field reversal was discovered, it says that a tree which lived during the time period of the field reversal was discovered. The reversal(s) of the Earth's magnetic field throughout history have been known for some time. The discovery of this tree is just about finding a very specific snapshot of that reversal taking place.
It's as if there was a story saying, "Video of Hillary Clinton deleting 30,000 official emails has been found." The video is a more detailed corroboration of something we already knew.
I would imagine it would be a similar process. But this is the first time I Read about tree rings.
Think of the fortune in lumber that could be milled from that thing. How many 40,000 year old table tops could you make from that, and what would people pay for them -- a lot I'd guess.
They switched to GPS.
Gulls Pointing South?.......................
I thought that was on the ocean’s floor where the changes reflect a zebra-striped pattern. So the tree rings have iron cells or compounds that line up?
Heh... depends on the structural integrity of the wood.
"Swamp kauri, sometimes marketed as "ancient kauri", are prehistoric kauri trees (Agathis australis), buried and preserved in peat up to 50,000 years ago in New Zealand's North Island.[1][2] Buried under a peat swamp by an unexplained act of nature at the end of the last Ice Age, the trees have survived the centuries underground, sealed in a chemically balanced environment that has preserved the timber in perfect condition.[3]"
"The trees grew for nearly 2000 years before they were buried. Some have a girth of around 40 feet, and a total height of nearly 200 feet."
See my post #34.
Ancient Northland kauri tree reveals secrets of Earth's polar reversal
Paleomagnetic Dating uses dendrochronological sequences where available and apropos to track the shifting locations of the magnetic pole based on remanent magnetic fields expressed in baked clay objects and long slow deposits of magma. The magnetic pole shift recorded in layers of rock at the major plate boundaries was instrumental in the so-called plate tectonics revolution in the 1950s-60s. This particular sample is huge, and right near the RC limit, although I'm not too sure this is absolutely the first time it's been done this way. There's obviously an advantage to having the magnetic field lines recorded in the actual sample that is getting RC dated.
Thanks blam. I like the sound of that, "unexplained act of nature".
We’re all gonna DIE!!!
‘Face
;o])
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