Posted on 04/06/2015 5:26:46 AM PDT by ckilmer
October 17, 2012 in Geology & Climate
During the last ice age, around 41,000 years ago, there was a very rapid and complete reversal of the Earth’s geomagnetic field, according to new research. There was already localized evidence of polarity reversals during this time, but with the new research, the theory that it was a global event is now strongly supported. And very interestingly, it is one that nearly coincided with the very fast, short-term climate variability of the last ice age and the largest volcanic eruption in the northern hemisphere during the last 100,000 years.
Magnetic studies using sediment cores taken from the Black Sea, done by the GFZ German Research Centre for Geosciences, have clearly shown that if you had a compass at the Black Sea during that time, it would have pointed towards the south, not the north.
But more importantly, new data gathered by the researchers when it’s combined with additional data from previous studies in the North Atlantic, the South Pacific, and Hawaii, strongly supports the theory that this polarity reversal was truly global.
What’s considered so remarkable about this reversal is the speed that it’s now thought to have occurred: “The field geometry of reversed polarity, with field lines pointing into the opposite direction when compared to today’s configuration, lasted for only about 440 years, and it was associated with a field strength that was only one quarter of today’s field,” explains Norbert Nowaczyk. “The actual polarity changes lasted only 250 years. In terms of geological time scales, that is very fast.”
The magnetic field at the time would have only had about 5% of the strength of the field today. This would have resulted in the Earth almost completely losing its protective shield, allowing hard cosmic rays to hit the surface, and greatly increasing radiation exposure.
“This is documented by peaks of radioactive beryllium (10Be) in ice cores from this time, recovered from the Greenland ice sheet. 10Be as well as radioactive carbon (14C) is caused by the collision of high-energy protons from space with atoms of the atmosphere.”
The polarity reversal observed in the magnetisation of Black Sea sediments isn’t new knowledge, though — it’s been known of for at least 45 years. First discovered in “the analysis of the magnetisation of several lava flows near the village Laschamp near Clermont-Ferrand in the Massif Central, which differed significantly from today’s direction of the geomagnetic field.” This geomagnetic feature has since then been called the Laschamp event.
That’s limited data though, representing only some specific point readings of the geomagnetic field during that time, so there had been debate about how to interpret it. When combined with all of the new data though, it creates a convincing image of “geomagnetic field variability at a high temporal resolution.”
The cores analyzed also provided insight into “numerous abrupt climate changes during the last ice age” that occurred at the same time — these climate changes had already been observed in ice cores taken from Greenland. “This ultimately allowed a high precision synchronisation of the two data records from the Black Sea and Greenland.”
“The largest volcanic eruption on the Northern hemisphere in the past 100,000 years, namely the eruption of the super volcano 39,400 years ago in the area of today’s Phlegraean Fields near Naples, Italy, is also documented within the studied sediments from the Black Sea.”
This volcanic eruption released about 350 cubic kilometers of ash, rock, and lava over all of the eastern Mediterranean, and parts of Russia and Asia.
All three of these global disasters; a rapid and complete reversal of the Earth’s magnetic field, the drastic short-term climate variability of the last ice age, and one of the largest volcanic eruptions in the last million years; have now been tied together and placed into a precise and connected chronological order.
The new research was just published in the journal Earth and Planetary Science Letters.
Source: Helmholtz Centre Potsdam – GFZ German Research Centre for Geosciences
That is exactly what I was thinking. Can someone please explain how a reversible polarity could occur that would not be a worldwide event. We have known for over 50 years that spreading sea floor recorded evidence of repeatedly worldwide episodes of global reserve polarity over a period of millions of years.
Are these people that ignorant, or are they just spouting their political agenda?
Most likely agenda spreading.
Yah, and the info can be used to figure out how the wrath of God is going to be global, especially the great earthquake that flattens every city, the mountains, and islands. Plus heard when it flips the asteroids don’t bounce off.
But I do know how to measure magnetic fields, even over time, and the effect that mag fields have on high frequency radiation. That part is formulas, no prophecy required on my part.
/johnny
YOU HAVE MY UNDIVIDED ATTENTION.
Memo to self: next trip to Walmart, pick up some cosmic rayscreen.
From my undergratuate days in geology... it has happened many time... the reversal is recorded in the seafloor of the atlantic ocean... as it is spreding from the middle... the new sentiments record polarity... and it has recorded multiple switches.... at least during the widening of the Atlantic...
>>>Better wording....
From my undergratuate days in geology... it has happened many a time... the reversal is recorded in the seafloor bedrock of the Atlantic ocean... as it is spreading from the middle... the new multen rock records the current polarity (in the magnetic particles) as they cool to rock... the reversal has beeb recorded multiple times.... at least during the widening of the Atlantic...
Many many years ago, I tried to relate Velikovsky’s theories to events in Scripture but never could do so conclusively.
If I make a numerical outline of the coming disasters (like the 10 in Egypt that snowballed) would you be able to figure out if one caused the next, then the next?
Not that lots of people don't do it.
/johnny
The Bible is pretty explicit. One question I have always had is what would cause the earth to spin faster. Days are supposed to get shorter. It’s just fun to think about.
Spin a boiled egg on the table...spin a raw egg. If somehow the oceans were to become solid...
Many normal physical effects could cause the spin rate to increase. See any physics book about rotating bodies.
A skater spins faster when she draws her arms close to her. Same applies on a larger scale to whole planets. External planets (our moon) can also have an effect on radial velocity. As I said, check any modern physics textbook to see what causes a change in rotational chage. The guys pretty well have rotation nailed, as far as mundane causes are concerned. They will never say "Because God said so"
/johnny
Thanks ckilmer and BroJoeK. Two list ping!
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Thanks ckilmer and BroJoeK. Two list ping!
Good point.
I suspect you already know this. Birds use Earth’s magnetic field for migration.
What is the proportion of mass in water for the earth and the water is on the surface. If I were to spin the earth faster, would the centrifugal force be strong enough for us to lose atmosphere or water? For the earth to become solid the lava would have to cool, no?
Interesting!
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