Earth’s rapid magnetic field reversals
Published: 30 November 2014 (GMT+10)
Why has one author retracted?
The decay of the earth’s magnetic field is powerful evidence against the anti-biblical dogma of millions or billions of years. An important aspect of the physical model is rapid field reversals during the Flood, followed by damped oscillations for a time. This was first predicted by Dr Russell Humphreys, and the driving force was the upheavals related to catastrophic plate tectonics as per the well-supported model of Dr John Baumgardner. This prediction was vindicated by discoveries of thin lava layers that must have solidified in days, but recorded the earth’s magnetic field changing continuously as the different parts cooled. All this is explained in The earth’s magnetic field: evidence that the earth is young.
However, one correspondent asked us about a recent paper where one of the authors of the secular papers about rapid field reversals has retracted. Dr Humphreys responds, explaining that the retraction is most suspicious.
Firstly let me thank you for your wonderful collection of excellent, faith-building articles. I have been reading many about the rapid magnetic reversals. Many refer to Dr Russell Humphreys article Physical Mechanism for Reversals of the Earth’s Magnetic Field During the Flood and Dr Baumgardner’s Catastrophic Plate Tectonics model. In his article, Dr Humphreys appears to rely, somewhat on articles by Coe and Prévot about Steens Mountain rapid reversals. This has been great for a discussion that I’m involved in. Upon doing further reading I came across a [paper by Coe1] with a highlight being, “The case for extraordinarily rapid field change at Steens Mountain is now untenable.” How would this affect Drs Humphreys’ and Baumgardner’s works?
Dr Russell Humphreys responds:
Thanks for the question. The quick answer is that Coe et al. do not have very good experimental reasons for retracting. Just to compare the situation to something familiar, suppose Mary Schweitzer suddenly used a new and not-well-tested way to analyze dino soft material and announced that the new method shows there was no soft material, and so now she repents of her chutzpah2 in sackcloth and ashes? That will give you the flavor of this newest Coe article to me.
Next, notice that Michel Prévot is not one of the authors, nor is Pierre Camps. Both of those were co-authors with Coe in previous landmark papers on this topic. Coe has been under tremendous pressure to retract for the last two decades, and if he were to become accepted again within the fold, then his grad students and post-docs would not be looked at askance as they look for jobs. I think he would be enormously relieved to find a legitimate-appearing excuse to retract.
In the paper, Coe abandons the step-heating technique (very well-tested and relied upon since the 1940s) he had used: measuring a sample’s loss of magnetization as one takes it slowly through a series of small temperature steps. He also abandons the (not quite as reliable but still widely used) alternating-field demagnetization.
Instead, he uses a relatively new technique: rapid and continuous heating of a sample at 40 Celsius degrees per minute, measuring the demagnetization continuously. He invents a questionable scenario, “Thermal alteration”, which I wouldn’t think would apply to ordinary basalt well below its melting point. The fast-heating technique supposedly gives less time for thermal alteration. The new technique calls into question the earlier results, a steady change of magnetic direction, by about 60 degrees, for samples going deeper and deeper into the interior of the basalt slab. If the new method is right, it might call into question nearly 75 years’ worth of paleomagnetic conclusions based on the step-heating method.
In the normal step-heating method, the experimenter waits for several minutes at each temperature for the sample to get demagnetized. This emphasizes the larger grains of magnetic material that are (a) slower to change their magnetization at high temperatures and (b) were unlikely to change their magnetization after the basalt cooled. But in the fast continuous-heating method, the grains have only a few seconds to change their magnetization at each temperature. That tends to emphasize smaller grains that can change magnetization easily … and are therefore more likely to have been re-magnetized by thousands of years of the earth’s normal magnetic field after the rocks became cool.
So the old method looks at a more robust, magnetically ‘hard’ set of grains, but the new method looks at magnetically ‘soft’ smaller grains. The old method would not be much influenced by the smaller, ‘softer’ grains, so it should be a much more reliable way of determining the earth’s magnetic field while the basalt was cooling down below its Curie temperature, about 500°C. If secular paleomagnetic experts were not so eager to discard Coe’s earlier results, I think they would not be so eager to trust this new method.
New articles give evidence that the last magnetic polarity transition (during or just before the Ice Age, from reversed to normal) on the earth was very fast, probably taking less than a few months. If you can ignore the hype about possible future fast field flips, a pop-science article about it was titled, ‘Earth’s magnetic field could flip within a human lifetime’. 3 This was based on a technical paper, ‘Extremely rapid directional change during Matuyama-Brunhes geomagnetic polarity reversal’.4
These paleomagnetics researchers looked at Ice Age lake bed sediments in Italy and found that the last magnetic field flip took place within a sub-layer only 2 cm thick. Using Argon-Argon dating, they thought that the whole layer was laid down at about 0.2 mm per year, which is rather slow compared to lake sediments today. That would make the transition occur in less than 100 years, which is still blazingly fast compared to the usually-assumed transition times, hundreds of thousands of years to millions of years.
However, if one accounts for accelerated nuclear decay trailing off (but still significant) in the period after the Genesis flood, then the sediment deposition rate could easily become more like 4 cm/year, a quite reasonable rate during the stormy Ice Age. That would reduce the transition time to just a few months. That compares quite well with the evidence we have for fast reversals in the last stages of the Genesis flood. It supports the general picture we have of many fast reversals during the Genesis flood. That collapses the paleomagnetic time scale from Megayears down to months.
As for the pop-science writer’s speculation that the present decay of the earth’s magnetic field is moving toward a future fast reversal … I’m sorry to have to say that the fluid in the earth’s core is moving far more slowly now than it probably was just after the Genesis Flood. Every indication is that the decay today is simple power loss in the (turbulent) electrical resistance of the (turbulent but slow) core fluid. See my article ‘Planetary Magnetic Dynamo Theories: A Century of Failure’ in the 2013 ICC proceedings.5
Boring old resistive decay doesn’t make for exciting headlines, but fast past flips do!
Hoping this is helpful,
References and notes
- Coe R.S. et al., Demise of the rapid-field-change hypothesis at Steens Mountain: The crucial role of continuous thermal demagnetization, Earth and Planetary Science Letters 400:302–312, 15 August 2014; sciencedirect.com. Return to text.
- Chutzpah (Yiddish; Hebrew חֻצְפָּה) is a derogatory Jewish term for an unbelievable audacity, lack of remorse, and arrogance for some bad behaviour. One common illustration is a man who kills both his father and mother then demands sympathy because he’s now an orphan.—Ed. Return to text.
Science Daily, sciencedaily.com, 14 October 2014; summary: “Earth’s last magnetic reversal took place 786,000 years ago and happened very quickly, in less than 100 years—roughly a human lifetime. The rapid flip, much faster than the thousands of years most geologists thought, comes as new measurements show the planet’s magnetic field is weakening 10 times faster than normal and could drop to zero in a few thousand years.” Return to text.
- Sagnotti, L. et al., Extremely rapid directional change during Matuyama-Brunhes geomagnetic polarity reversal, Geophysical Journal International 199(2):1110–1124, November 2014 | doi: 10.1093/gji/ggu287. Return to text.
- Humphreys, R., Planetary magnetic dynamo theories: A century of failure, 7th ICC, 2013; creationicc.org. Abstract: “For nearly a century, geoscientists who believe the earth is billions of years old have been striving to develop a successful ‘dynamo’ theory to explain how the earth’s magnetic field might maintain itself over that long time. After reviewing analytic theories, computer simulations, and laboratory experiments, I have concluded that all those efforts have fallen short of proving the geomagnetic field could be maintained by a dynamo. To contrast with this apparent failure, I touch upon the remarkable success of creationist theories in explaining magnetic fields in our Solar system, especially the planet Mercury. This contrast supports the young Biblical age of the world, about 6,000 years.” Return to text.