Questions tagged [geomagnetism]
Questions regarding the magnetic field emanating from Earth's interior.
75 questions
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Why Is Radioactive Decay Essential in Maintaining the Earth's Magnetic Field?
I remember reading that the heat produced by decaying radioactive elements play an important role in maintaining the Earth's magnetic field. Is it true? If so, I would like to know how big of a ...
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Why doesn't the Earth's magnetic field go through its center
I once heard someone in my science club say that the magnetic field doesn't go through the center of the Earth. I then searched, but I don't think anything I wanted was found.
Does anyone know why?
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Precision of Geomagnetic Reference Field coefficient values for 1985
As per NOAA, DGRF values for 1985 are rounded to the nearest integer for 1995 and before. I recently stumbled upon some software code where for 1985 the harmonic coefficients had 1 extra significant ...
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Crustal magnetic field of the Earth
Where can I find an accurate map of the Earth's crustal magnetic field?
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What useful information could an ancient "mining compass" yield?
I read here and elsewhere that
Exploratory and reconnaissance surveys are frequently made with the aid of a magnetic compass [...] Early references to the application of the magnetic compass to ...
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Can the Lorentz force cause currents that accelerate electrons and cause auroras?
I'm asking this question based on a fragment of this (https://pubs.aip.org/physicstoday/article-abstract/61/7/68/1017143/How-do-auroras-form-A-key-element-is-a-current?redirectedFrom=PDF)
If the ...
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Does oxygen propagate towards stronger magnetic fields on Earth?
I noticed Earth has variations in gravity similar to focal points for magnetic fields, both macro and micro in size, caused by magnetic material deposits. With oxygen being attracted to magnets, I ...
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Do gravity and magnetic field change along a geographic latitude or not?
Along the same geographic latitude does magnetic field change or not, and the same for the gravitational field, does it change along a geographic latitude? Please explain.
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How can there be zero magnetic declination in places where the magnetic and geographic poles don't line up
Here's a global map of magnetic declination:
How can there be zero magnetic declination in places where the magnetic and geographic poles don't line up (which is only at approx. latitude 0 and 180 ...
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Safest place on Earth during the pole shift
Where is the safest place on Earth in relation the magnetic poles as it is moving that will provide the most protection against solar radiation? I imagine the topography may effect the magnetic fields....
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Earth magnetic field, WMM/IGRF
My question is about World Magnetic (WMM) and International Geomagnetic Reference Field (IGRF) models. It is well known that to a first approximation, earth magnetic field is a field of dipole. It ...
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Airborne geophysical survey in steep and undulating terrain. What is more important, energy conservation or orienting lines wrt to geology and why?
I am trying to design a cost and energy efficient aerial survey and have come up against the question, 'do we have to fly straight lines perpenducular to geology?' as not doing so could make for a ...
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Can paleomagnetic techniques determine the exact direction of Earth's magnetic poles in the past, not just their polarity?
Since our planet's magnetic poles are not usually, precisely, lined up with the geographic poles of Earth's axis, and since they move around a lot, can paleomagneticists (is that a word?) determine ...
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How accurate are paleomagnetic orientation measurements?
I am curious what the modern accuracy for paleomagnetic azimuthal orientation measurements are. Let's say for a magnetite grain, is the orientation of the magnetic moment for a single crystal resolved ...
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Why do electrons drift Eastwards in the Van Allen belts?
Context
The image below shows that one of the three particle movement patterns of radiation particles that are captured in the Van Allen belts is a longitudinal drift motion:
However, I am ...
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