Japan Geoscience Union Meeting 2014

Presentation information

Print

Oral

Symbol A (Atmospheric, Ocean, and Environmental Sciences) » A-HW Hydrology & Water Environment

[A-HW25_2AM1] Isotope Hydrology 2014

Fri. May 2, 2014 9:00 AM - 10:45 AM 414 (4F)

Convener:*Masaya Yasuhara(Geological Survey of Japan, AIST), Kohei Kazahaya(Geological Survey of Japan, AIST), Shinji Ohsawa(Institute for Geothermal Sciences, Graduate School of Science, Kyoto University), Masaaki Takahashi(Geological Survey of Japan (GSJ), National Institute of Advanced Industrial Science and Technology (AIST)), YUICHI SUZUKI(Faculty of Geo-Environmental Sience,Rissho University), Futaba Kazama(Social Cystem Engineering, Division of Engineering, Interdiciplinary Graduate School of Medical and Engineering, University of Yamanashi), Kazuyoshi Asai(Geo Science Laboratory), Chair:Masaya Yasuhara(Geological Survey of Japan, AIST), Noritoshi Morikawa(Geological Survey of Japan, AIST)

9:00 AM - 9:15 AM

★ [AHW25-01] Radon Concentration around Tachikawa Active Fault

*Fumiaki TSUNOMORI1 (1.Graduate School of Science, University of Tokyo)

Keywords:Grounwater, Hot Spring, Radon, Active Fault

Characteristics of a radon concentration distribution around the Tachikawa active fault will be focused in this report.According to the Headquarters for Earthquake Research Promotion, occurrence potentials of earthquake in active faults in Japan were updated after the Tohoku Earthquake (March 11, 2011). The report denotes the potential of the Tachikawa active fault while next 30 years was increased from 0.5-2% to 0.9-2%. In order to monitor a state change of the fault system by groundwater analysis, we have been surveying water qualities of spring water and hot-spring water.Our survey of shallow spring waters around the fault in 2012 revealed that the radon concentration of shallow groundwater was affected by a cultivation process of groundwater on the ground surface around the northwest area of the Tama district. Therefore the shallow groundwater around the fault is not appropriate to get information on the state change of the fault. Our survey of deep hot-spring water around the fault in 2013 indicated the good relation between the radon concentration distribution and the location of the fault. The nearer the location of the hot-springs to the fault is, the higher the radon concentration becomes. Therefore the deep groundwater around the fault is useful to monitor the state change of the fault.