Posted on 11/09/2017 8:55:11 AM PST by MtnClimber
The Earth’s magnetic field, generated some 3,000km below our feet in the liquid iron core, threads through the whole planet and far into space – protecting life and satellites from harmful radiation from the sun. But this shielding effect is far from constant, as the field strength varies significantly in both space and time.
This “geomagnetic spike” offers a potentially profound new insight into the dynamics and evolution of Earth’s hidden interior that is now starting to be uncovered.
So what are geomagnetic spikes and what are the prospects and implications of another one coming along? The geomagnetic spike of 1000BC was first identified from copper slag heaps located in Jordan and Israel. These were dated from organic material within the slag heaps using radiocarbon dating.
Scientists then investigated the copper using sophisticated laboratory techniques to work out what the Earth’s magnetic field was at the time – relying on the fact that when melted iron cools rapidly, it freezes with a signature of the field at that instant. By taking samples from different layers of the slag heap – with slightly different ages and magnetisation – they could also see how the field strength changed with time. They found that the copper slag had recorded Earth’s magnetic field strength rising and then falling by over 100% in only 30 years.
Unexpectedly high field strengths around 1000BC have also been uncovered in Turkey, China and Georgia from a variety of sources. Remarkably, the field strength in India, Egypt and Cyprus around the same time was completely normal, indicating that the spike was perhaps only 2,000km wide. Such a rapid change over such a small area marks out the geomagnetic spike as one of the most extreme variations of Earth’s magnetic field ever recorded.
(Excerpt) Read more at realclearscience.com ...
That is really strange!
1000 BC would be around Saul, David and Solomon’s time.............
What was going on with the Hebrews in 1000 BC?
I hope that when they took their core samples, they remembered that the act of cutting the sample will introduce a magnetic field of its own from the work hardening during the cutting process.
So these samples might just be unusable for measuring residual magnetism.
Clearly this will cause climate change is its Trumps fault.
Not only did he personal cause the spike ~3000 years ago, but he is planning to cause another one which will obviously benefit the rich and hurt the poor.
OK... honestly, I don’t understand how gravity can leave it’s signature on cooper as it cools. Perhaps we humans really don’t understand how this universe actually works?? Maybe?
They’re going to figure out that the Earth’s center is made of nougat.
Where is Giorgio Tsoukalos ?
The primary tenet of geology is that processes operating in the past are still operating today. Just because we don’t have an obvious magnetic spike now does not mean that the process causing them has ceased.
That’s fascinating, particularly the variation from point to point. What in the mantle would cause those differences?
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