火山噴火予知研究推進センター霧島火山観測所
火山噴火予知研究推進センター, (東京大学地震研究所)
Kirishima Volcano Observatory, Volcano Research Center
VolcanoResearch Center, (Earthquake Research Institute，University of Tokyo)
抄録
Kirishima Volcano Observatory of Earthquake Research Institute initiated geomagnetic observations in the Kirishima volcanic area, since the earthquake swarm and minor eruption in Shinmoedake in 1991. This paper reports anomalous geomagnetic changes associated with volcanic activities of Shinmoedake. Abnormal changes were recognized at a northern part of the valcano, not at the center, suggesting a complex pattern of the anomaly. Closer observations at multiple sites near volcano would be needed in the future to infer the pattern of the anomaly correctly. An anomalous change as large as 10 nT was recognized in the last 3 years between nearby stations of Shinmoedake and the Kirishima Volcano Observatory, and the whole regions may be undergoing large-scale geomagnetic changes. Geomagnetic noises are very low and changes as low as 0.2 nT in the Shinmoedake area can be detected in the region. Kirishima may be an ideal field for close geomagnetic observation in the future.
霧島火山群における地磁気観測
01_018-022.pdf
(10.33MB)
