Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6335136 | Applied Geochemistry | 2014 | 8 Pages |
Abstract
Dating using a combination of 3H and 3He is believed to be the most practical method for estimating the short residence time of shallow groundwater. However, this method must estimate tritiogenic 3He alone and tends to overestimate the residence time of groundwater, if terrigenic 3He from the mantle cannot be excluded from the total dissolved 3He. We demonstrate the exclusion of terrigenic 3He in the Saijo Basin, where mantle He is easily released along the major active fault, Median Tectonic Line. The 3He/4He ratios suggest that the west bank of the Kamo River, which lies within the basin, has experienced greater emanations of mantle He than the east bank. We estimate the residence times to be 1.1-96Â years by the proposed exclusion method.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Geochemistry and Petrology
Authors
Yasunori Mahara, Tomoko Ohta, Noritoshi Morikawa, Takanori Nakano, Minoru Tokumasu, Satoshi Hukutani, Tomochika Tokunaga, Toshifumi Igarashi,