The Geomagnetic Coast Effect
Speaker: Yuan-Chung Yang Advise: Horng-Yuan Yen
Abstract
The vertical component of the geomagnetic variation field will become larger at the coast line, and there is a correlation between the vertical component and the inland horizontal component. The phenomenon is known as the geomagnetic coast effect. To study this phenomenon, we use the relationship between the horizontal component and the vertical component of the variation field to obtain the azimuth of this effect. As the secondary filed of the geomagnetic field changes, the induction electric current also creates an opposite induction magnetic field to the secondary field. As the earth is a conductor that its conductivity is a complicated function of location, the induced electric current will flow toward the area that shows higher conductivity and the induced magnetic field will occurs close to the boundary of these materials. The Parkinson vectors indicated the direction of the high conductivity area and the magnitude of the conductivity contrast.
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