2015 Fiscal Year Final Research Report
Determination of the electromagnetic field arising from time-dependent piezomagnetic effect during ruptures
Project/Area Number |
26800233
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Research Category |
Grant-in-Aid for Young Scientists (B)
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Allocation Type | Multi-year Fund |
Research Field |
Solid earth and planetary physics
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Research Institution | Kyoto University |
Principal Investigator |
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Project Period (FY) |
2014-04-01 – 2016-03-31
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Keywords | 電磁場変動 / 地震 / 弾性波動場 / 応力磁気効果 / 電気伝導度 / 観測可能性 / 早期地震警報 / 時間領域 |
Outline of Final Research Achievements |
There are several reports on electromagnetic (EM) signals that are observed a few seconds prior to arrival of seismic waves. A candidate mechanism that generates such EM signals is the piezomagnetic effect, that is, changes in magnetization corresponding to changes in applied stress. The objective of this project is to derive a set of equations that describes EM signals from the piezomagnetic effect, and to answer whether the piezomagnetic effect accounts the earlier reports or not. I successfully derived the desired equations. Numerical considerations using the obtained equations suggest that EM variations from the piezomagnetic effect during ruptures are not large enough to be observed by using the present technique of observation. This means that EM signals prior to seismic waves should be accounted by other mechanisms.
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Free Research Field |
地球電磁気学
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