© 2018 B. L. Freeborn
In the previous posts the magnetic strength of each major layer of Earth was discussed. The next step is to look into the idea that the poles of the earth just flip. This is an idea that has become very popular but is it valid?
There was a video here that depicted the reprogramming of magnetic orientation (if it occurs slowly) or the flipping of poles (if instant). !!
The best way to approach the idea that Earth’s poles can flip is to think about it extensively first. Here are three thought exercises:
- Hold a magnet in your hand firmly. Allow this to be the exterior mass of Earth. Now without moving your hand get the poles to flip. How can it be done?
- Hold a magnet in your hand firmly. Allow this to be the interior solid core of Earth. Now without moving your hand get the poles to flip. How can it be done?
- Hold a magnet in your hand firmly. Allow the magnet to represent a single layer of sedimentary rock that has recorded the current magnetic field. (In reality they are stacked one on the other in different directions recording its movement.) If the outer shell of Earth is rigid and does not move, how can you shift the magnet’s field by 25 degrees in either direction without moving your hand to simulate the direction of the next sedimentary layer? Remember plate tectonics is gradual so that is not an option.
- There are only two ways to get the poles to flip without moving your hand:
-Hold onto the magnet until it loses its magnetism (a very long time) and then expose it to a magnet or electric field with an opposing charge. It will reorient itself accordingly. But that can hardly be called flipping. That is reprogramming it.
-Hold onto the magnet and expose it to a much much larger and stronger magnetic field. It will flip instantly. What could in reality supply such a field to the Earth? A near miss by a larger planetary type body with a greater magnetic field would do it but it is not likely to happen since large free moving bodies are more rare than comets.
-There are variations on this but it still requires bringing other very strong magnetic fields into close proximity. So…. essentially it just does not happen.
- The poles of the inner core cannot be flipped except as noted in 1. Flipping the interior solid core as a whole is perhaps easier but this is not a flipping of the poles. The solid round core will just rotate within the liquid core. In order to do this, the inner core must be in a magnetically locked position with the outer crust. When the outer crust rotates so does it. Then to flip the pole spinning the planet completely over is required.
-But we might assume it is always magnetically locked to the outer crust. If it were to break the lock, it would be free to rotate. Although it is a large mass that is hurtling through space around the Sun its momentum would not prevent its rotation since it should be free to rotate around its own center of gravity. This case shall be considered in the future and it will be discussed just how far it can rotate until it locks up again. So ….essentially it can happen but probably less often then a partial rotation.
- How does one lay down the next magnetic layer in the sedimentary layers without moving the old sedimentary layers? If the crust cannot and does not move then the field must, and this is what fuels experiments today and defines the current understanding of Earth’s magnetism.
There is an underlying unspoken consensus in the scientific community that the crust/mantle system of the Earth always has been in the position it is today with North America and Russia nicely dominating the northern hemisphere. Period. Except during the time of the single Pangaea which is too long ago to explain modern phenomena and then artists still show only the southern continents moving away.
There are only three options then: have a perpetually shifting field, overwhelming influence the field externally or move the magnet itself. Modern models are firmly based in the first. The second cannot happen as often as the rock record suggests which leaves the last. It is anathema to the modern scientist to consider that the planet is a layered structure which responds accordingly. It is also forbidden to suggest that the planet is subject from time to time to extreme impacts which can shift the bulky outer 1800 mile layer in relation to the inner core and the ecliptic plane.
This is not as proposed by Charles Hapgood’s popular theory who only envisioned the outer 60 miles, lithosphere, moving on the 460 mile thick semi-lava layer, the asthenosphere. The difference is like trying to slide a rubber tire directly on the rim vs. moving the tire and rim around on a free axle. Since the viscosity of the outer liquid core is said to be less than that of water, it is essentially a free axle.
So …. in the next post let us look at the rock record that indicates the core flips.