Minor Earthquake Activities
Ground Deformation
Anomaly of Electromagnetic Field
Calling of  Apes
Atmosphere Anomaly
The Warning Earth light
Alarm of the Nature - Earth Sound
Gossips about Earthquakes



All Kinds of Earth Light

Records on the Bamboo

20 Examples of Rescue

Seismic Belts in China

Ground Deformation

Calling of Apes

Key Points for Escape

When Pressed Down


Anomaly of Electromagnetic Field

  In 1855, there was a Japanese businessman, who ran a spectacle shop. He used to attract customers with a horseshoe magnet, which attracted a lot of needles. But, on that day when an earthquake happened to his city, the iron needles and other small objects fell on the ground abruptly and he was quite shocked. Two hours later, a destructive earthquake happened. After the earthquake, the magnet started to attract iron again.

  Mankind got to know the change of magnetism fields before earthquakes quite early. 

  Earthquakes can result in the change in electromagnetic fields. Generally, there were two reasons for such changes. One is that, under the reaction of the earth stress, the effect of "piezomagnetic effect" would happen to rocks, thus, result in the partial change in geomagnetic field; the other reason is that, the earth stress would condense or extend the rocks, which would also results in partial changes in electrical resistivity, which would in turn cause partial change to the electromagnetic field. The change of temperature in rocks could also bring changes to the electromagnetic property. Therefore, to observe the change of electromagnetic field is also one on the major method to forecast earthquakes.





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