228Ra/226Ra activity ratio in groundwater around Mount Fuji, Japan

Abstract

We estimated the groundwater age from 228Ra/226Ra ratios in young groundwater and relevant rocks in the volcanic area of the Kakitagawa River around Mount Fuji, Japan, and compared our results with those from 3H/3He age determination. The groundwater residence time estimated from the 228Ra/226Ra activity ratio in groundwater and relevant rocks agreed well with the 3H/3He age, suggesting that the 228Ra/226Ra ratio of groundwater can be used to estimate residence time of young groundwater in volcanic areas. © Owned by the authors, published by EDP Sciences -SIF, 2012.