2011 Volume 131 Issue 9 Pages 678-683
We have observed and recorded the neutral current of a 500 kV transformer at a substation in Chubu region since 2008 in order to detect electromagnetic anomalies associated with earthquakes. In this observation, we could not find any particular anomalous change of the neutral current before and after earthquakes (e.g. The Suruga Bay Earthquake occurred on August 11, 2009).
However, from the result of a quantitative analysis between geomagnetic field data and neutral current data, we would be able to investigate the underground electric conductivities near the substations. It would be possible to monitor the change of electromagnetic structure of underground before and after earthquakes.