学術雑誌論文 Groundwater helium anomaly reflects strain change during the 2016 Kumamoto earthquake in Southwest Japan

Sano, Yuji  ,  Takahata, Naoto  ,  Kagoshima, Takanori  ,  Shibata, Tomo  ,  Onoue, Tetsuji  ,  Zhao, Dapeng

6p.37939 , 2016-11-29 , Nature Publishing Group
ISSN:2045-2322
内容記述
Geochemical monitoring of groundwater and soil gas emission pointed out precursor and/or coseismic anomalies of noble gases associated with earthquakes, but there was lack of plausible physico-chemical basis. A laboratory experiment of rock fracturing and noble gas emission was conducted, but there is no quantitative connection between the laboratory results and observation in field. We report here deep groundwater helium anomalies related to the 2016 Kumamoto earthquake, which is an inland crustal earthquake with a strike-slip fault and a shallow hypocenter (10 km depth) close to highly populated areas in Southwest Japan. The observed helium isotope changes, soon after the earthquake, are quantitatively coupled with volumetric strain changes estimated from a fault model, which can be explained by experimental studies of helium degassing during compressional loading of rock samples. Groundwater helium is considered as an effective strain gauge. This suggests the first quantitative linkage between geochemical and seismological observations and may open the possibility to develop a new monitoring system to detect a possible strain change prior to a hazardous earthquake in regions where conventional borehole strain meter is not available.
UTokyo Research掲載「地下水のヘリウム量は大地震の前触れを告げる指標になりうるか」 URI: http://www.u-tokyo.ac.jp/ja/utokyo-research/research-news/groundwater-helium-level-could-signal-potential-risk-of-earthquake.html
UTokyo Research "Groundwater helium level could signal potential risk of earthquake" URI: http://www.u-tokyo.ac.jp/en/utokyo-research/research-news/groundwater-helium-level-could-signal-potential-risk-of-earthquake.html
本文を読む

https://repository.dl.itc.u-tokyo.ac.jp/?action=repository_action_common_download&item_id=756&item_no=1&attribute_id=19&file_no=1

このアイテムのアクセス数:  回

その他の情報