Japan Geoscience Union Meeting 2015

Presentation information

Poster

Symbol A (Atmospheric and Hydrospheric Sciences) » A-HW Hydrology & Water Environment

[A-HW24] Isotope Hydrology 2015

Mon. May 25, 2015 6:15 PM - 7:30 PM Convention Hall (2F)

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(The National Institute of Advanced Industrial Science and Technology), 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)

6:15 PM - 7:30 PM

[AHW24-P03] Effects of mountainous water recharge to groundwater quality of alluvial fan

*Takashi NAKAMURA1, Kei NISHIDA1, Futaba KAZAMA1 (1.ICRE, University of Yamanashi)

Keywords:Groundwater recharge, Alluvial fan, Isotopes, End-member mixing analysis, Mountainous water resource

In this study, the hydrogen and oxygen stable isotopes (dD and d18O) and chemical compositions of environmental water were employed to identify the effects of mountainous water recharge for groundwater quality on alluvial fan.
The study area is Midaigawa alluvial fan, located in western Kofu basin on central Japan, which is formed by Raised-bed River discharged from the mountain watershed.
The groundwater samples were collected from 25 deep wells (100~300m) in June-2010, Novenber-2011 and Novenber-2012. Those wells were located on Midaigawa alluvial fan and adjacent mountain. Four End-member mixing analysis using isotope value and chemical compositions revealed spatial variation in the contribution ratios for various groundwater sources. This presentation focused on groundwater recharge from mountain area to alluvial fan. It also found the relationship between contributions of mountainous water on groundwater and chemical composition.

Acknowledgment
This study was supported by the Kurita water and environment Foundation (No.14B063).