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 ...
The kauri tree unearthed during the expansion of the Ngawha Generation geothermal power plant. Nelson Parker
Nuts! Here's that text with the typos corrected.
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.
Okay, so, I live to take risks and live my online life on the edge.
Don’t ever base a theory on just one tree.
Is there a truncated version?
There is evidence of many pole reversals on the bottom of the Atlantic Ocean. When looking at the Iron on the sea floor, it is aligned in different directions—North and South. If you were to color one direction white and the other black, the pattern would look like a zebra.
It is a fairly regular event and nothing to really get worked up about.
How do the changes in the rings reflect changes in the magnetic fields?
I see what you did there.
Maybe I should have asked you about post #8.
Iron in the cells is lined up on the then-current magnetic field lines.
They inferred a "NEAR reversal" NOT "Magnetic Field Reversal"!!!!
Second, Nobody explains the uniqueness of finding a 40,000 year old tree that HAS NOT BEEN PETRIFIED!!!!!!
Third, they don't explain how the tree rings revealed changes in the Earth's magnetic field.
EiU, p 146 (and referred to on p 202):The observation was made on clay fired in kilns by the Etruscans and Greeks. The position of the ancient vases during firing is known. They were fired in a standing position, as the flow of the glaze testifies. The magnetic inclination or the magnetic dip of the iron particles in the fired clay indicates which was the nearest magnetic pole, the south or the north.
In 1896 Giuseppe Folgheraiter began his careful studies of Attic (Greek) and Etruscan vases of various centuries, starting with the eighth century before the present era. His conclusion was that in the eighth century the earth's magnetic field was inverted in Italy and Greece. Italy and Greece were closer to the south than to the north magnetic pole.
P.L. Mercanton of Geneva, studying the pots of the Hallstatt age from Bavaria (about the year -1000) and from the Bronze Age caves in the neighborhood of Lake Neuchatel, came to the conclusion that about the tenth century before the present era the direction of the magnetic field differed only a little from its direction today, and yet his material was of an earlier date than the Greek and Etruscan vases examined by Folgheraiter. But checking on the method and the results from Folgheraiter, Mercanton found them perfect.
An ancient vase found by F.A. Forel in Boiron de Morges, on Lake Geneva, was broken and its pieces were scattered and lay in all directions; when assembled, they all showed one and the same magnetic orientation, which proves again that the magnetic field of the earth was unable to change the orientation originally acquired by the clay when fired and cooled in the kiln.
Large changes of the earth's magnetic fields in historical timesBy measuring the magnetic properties of bricks and other accurately dated human artifacts, geophysicists can reconstruct the history of the local magnetic field. Near Loyang, China, the field was as much as 54% higher in 300 A.D. than it is now. It was 15% higher in 1500 A.D. In 1000, it was less than today's value.
by William R. Corliss
Science Frontiers #22: Jul-Aug 1982
(Wei, Q.Y., et al; "Intensity of the Geomagnetic Field near Loyang, China, between 500 BC and AD 1900," Nature, 296:728, 1982.)
Comment. Direct measurements of the earth's field go back only a few hundred years, but they are consistent with the data reconstructed from artifacts, both showing a steady decrease since 1500. No one has estimated the effects of these substantial changes on radiocarbon dating and, perhaps, human biology.
"Earth In Upheaval", Immanuel Velikovsky, p 133Most interesting is the discovery that the last time the reversal of the magnetic field took place was in the eighth century before the present era, or twenty-seven centuries ago. The observation was made on clay fired in kilns by the Etruscans and Greeks.
The position of the ancient vases during firing is known. They were fired in a standing position, as the flow of the glaze testifies. The magnetic inclination or the magnetic dip of the iron particles in the fired clay indicates which was the nearest magnetic pole, the south or the north.
In 1896 Giuseppe Folgheraiter began his careful studies of Attic (Greek) and Etruscan vases of various centuries, starting with the eighth century before the present era. His conclusion was that in the eighth century the earth's magnetic field was inverted in Italy and Greece. 7 Italy and Greece were closer to the south than to the north magnetic pole.
P. L. Mercanton of Geneva, studying the pots of the Hallstatt age from Bavaria (about the year 1000) and from the Bronze Age caves in the neighborhood of Lake Neuchatel, came to the conclusion that about the tenth century before the present era the direction of the magnetic field differed only a little from its direction today, and yet his material was of an earlier date than the Greek and Etruscan vases examined by Folgheraiter. But checking on the method and the results of Folgheraiter, Mercanton found them perfect.
An ancient vase found by F. A. Forel in Boiron de Morges, on Lake Geneva, was broken and its pieces were scattered and lay in all directions; when assembled, they all showed one and the same magnetic orientation, which proves again that the magnetic field of the earth was unable to change the orientation originally acquired by the clay when fired and cooled in the kiln. 8
These researches, continued and described in a series of papers by Professor Mercanton, presently with the Service Meteorologique Universitaire in Lausanne, show that the magnetic field of the earth, not very different from what it is today, was disturbed sometime during or immediately following the eighth century to the extent of complete reversal.
[footnotes]
7 G. Folgheraiter in Rendi Conti del Licet, 1896, 1899; Archives des sciences physiques ei naturelles (Geneva). 1899; Journal de physique, 1899; P. L. Mercanton, "La m&hode de Folgheraiter et son r61e en geophysique," Archives des sciences physiques et naturelles. 1907.
8 Bulletin de la Societe Vaudoise des sciences naturelles, Stance du 15 decembre 1909.
9 Manley speaks of "the possibility of its [earth's magnetic field] reversal in historical times, 2500 years ago, to be cleared up by more research." However, the more exact date is, according to the original works of Folgheraiter and Mercanton, the eighth century before the present era, or shortly thereafter.
All we have to do is just rename NORTH and SOUTH...............and teach migratory birds to fly backwards...........
Almost reversed, because all the magnetic pole shifts have been random amounts. The magnetic pole used to run through Arabia, for example. IOW, the headline isn't misleading at all.
Petrification takes some length of time, or is a sudden process related to short-lived events (the latter would be suggested if this turns out to be an entire forest's worth of trees).
https://www.pbs.org/newshour/science/dogs-poop-in-alignment-with-earths-magnetic-field-study-finds
Just several versions that sort of branch off.
Everybody knows it's about the birds....
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