| Co-Investigator(Kenkyū-buntansha) |
KITA Itsuro Faculty of Engineering and Resource Science, University of Akita, Professor, 工学資源学部, 教授 (10143075)
IGARASHI George Graduate School of Science, The University of Tokyo assistant professor, 大学院・理学系研究科, 助教授 (00202854)
|
|---|
| Research Abstract |
It is reported that Greek physicists group has succeeded to predict occurrences of earthquakes by means of electro-magnetic observations. While, groundwater anomalies prior to or at the time of earthquakes were often observed in Japan, China and Russia. The aim of this study is to try to detect the groundwater anomalies in Greece where the electro-magnetic anomalies appeared many times, and to make clear the mechanism of the earthquake precursors. In 1998, we we installed a continuous Rn monitoring system at Atalanti No.2 well (111m deep with a screen of 66-105m denth) along the Atalanti active fault, where big earthquakes took place on May 23, 1893 (M 6.3) and on April 27, 1894 (M 7.2) with a lot of human victims. Our system consists of a water-gas separator module to extract soluble gases from groundwater, a Lucas cell-attached scintillation counter for Rn measurement and a recorder. In 1999, we installed the same systems at Atalanti No.3 well (150m deep with a screen of 102-132m death) and at Kamena Volla (self-spouting) well, 10km and 50km west of the Atalanti No.2 well along the Atalanti fault, respectively. This system sometimes didn't work, caused by water condensation in the Lucas cell and its surrounding tubes. So, we attached a water separation apparatus in all systems in March 1999. During our observation periods, Rn concentration changes possibly associated with small scale of nearby earthquakes (M2.8-3.2) were recorded on Oct.16, Dec.16 and Dec.21, 1998, at Atalanti No.2 well. We have also carried out continuous measurement of fumarolic gas temperature at Nysiros volcano, where volcanic earthquakes were taking place. In addition, we have investigated chemical and isotope features of groundwater and deep gas in view point of subduction tectonics.
|
