Do the magnetic poles of Earth have fixed positions?
The magnetic field extends into space for a distance of many Earth radii. Neither of them can be assigned a fixed geographical position because, due to magnetic storms and constant variations in the circulation of iron in the liquid outer core, their locations are constantly changing.
How is Earth’s magnetic field maintained?
It is continuously generated by the motion of liquid iron in Earth’s outer core, a phenomenon called the geodynamo. Despite its fundamental importance, many questions remain unanswered about the geodynamo’s origin.
What causes Earth’s magnetic poles?
The magnetic field is generated by electric currents due to the motion of convection currents of a mixture of molten iron and nickel in Earth’s outer core: these convection currents are caused by heat escaping from the core, a natural process called a geodynamo.
How do Earth’s magnetic poles work?
Instead, Earth’s magnetic field is caused by a dynamo effect. On Earth, flowing of liquid metal in the outer core of the planet generates electric currents. The rotation of Earth on its axis causes these electric currents to form a magnetic field which extends around the planet.
Is Magnetic North a stationary fixed point on the globe?
The earth’s geographic poles are generally right where you would expect them to be: at the two opposing points about which the Earth seems to rotate. Magnetic poles used in compass navigation are another matter altogether. And neither pole pair is completely stationary.
How can Earth’s magnetic reversal be used to support seafloor spreading?
When the Earth’s magnetic field reverses, a new stripe, with the new polarity, begins. Such magnetic patterns led to recognition of the occurrence of sea-floor spreading, and they remain some of the strongest evidence for the theory of plate tectonics.