caa a22 4500 445814470 CHVBK 20180317145221.0 cr unu---uuuuu 170323e20110201xx s 000 0 eng 10.1007/s10040-010-0638-5 doi (NATIONALLICENCE)springer-10.1007/s10040-010-0638-5 A multiple-isotope (δ37Cl, 14C, 3H) approach to reveal the coastal hydrogeological system and its temporal changes in western Kyushu, Japan [Elektronische Daten] [Tomochika Tokunaga, Jun Shimada, Yuki Kimura, Daisuke Inoue, Katsuro Mogi, Kazumi Asai] Une approche multi-isotopique (δ37Cl, 14C, 3H) mettant en évidence le système hydrogéologique côtier et son évolution, Kyushu de l'Ouest, Japon Multiple isotopes were used to reveal the coastal hydrogeological system and its temporal changes, caused by transgression and deposition of marine clay, in a small catchment and its offshore extension in Kyushu, Japan. Chloride concentrations in extracted pore waters from an offshore borehole were higher than 16,400mg/L at depths shallower than 1.5meters below sea floor (mbsf), and decreased downwards gradually to become lower than 250mg/L below 7.7mbsf. Stable chlorine isotopic ratios were -1.50‰ at 6.2mbsf and -1.27‰ at 5.6mbsf, while those from other depths showed minor fluctuation. A one-dimensional diffusion-sedimentation model was successfully applied to explain both chloride and stable chlorine isotopic ratios. Apparent residence times of groundwater below the inter-tidal zone is on the order of 100years while that below sea bottom is about 2,000years, indicating that groundwater below the inter-tidal zone constitutes a part of the present-day active groundwater flow system while that below sea bottom moves extremely slowly. The coincidence of the apparent residence time of groundwater below sea-bottom and the age of the start of both deposition of marine clay and diffusion processes strongly suggests that the deposition of marine clay has controlled the hydrogeological system and resulted in the reduction of the extent of groundwater discharge. Springer-Verlag, 2010 Salt-water/fresh-water relations nationallicence Stable chlorine isotopes nationallicence Groundwater age nationallicence Diffusion nationallicence Japan nationallicence Tokunaga Tomochika Department of Environment Systems, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, 277-8563, Chiba, Japan aut Shimada Jun Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto-shi, 860-8555, Kumamoto, Japan aut Kimura Yuki Department of Environment Systems, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, 277-8563, Chiba, Japan aut Inoue Daisuke Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto-shi, 860-8555, Kumamoto, Japan aut Mogi Katsuro Department of Systems Innovation, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, 113-8656, Tokyo, Japan aut Asai Kazumi Geoscience Laboratory Corporation, 1-608 Uedahonmachi, Tenpaku-ku, 468-0007, Nagoya, Japan aut Hydrogeology Journal Springer-Verlag 19/1(2011-02-01), 249-258 1431-2174 19:1<249 2011 19 10040 https://doi.org/10.1007/s10040-010-0638-5 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10040-010-0638-5 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Tokunaga Tomochika Department of Environment Systems, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, 277-8563, Chiba, Japan aut NATIONALLICENCE 700 1- Shimada Jun Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto-shi, 860-8555, Kumamoto, Japan aut NATIONALLICENCE 700 1- Kimura Yuki Department of Environment Systems, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, 277-8563, Chiba, Japan aut NATIONALLICENCE 700 1- Inoue Daisuke Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto-shi, 860-8555, Kumamoto, Japan aut NATIONALLICENCE 700 1- Mogi Katsuro Department of Systems Innovation, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, 113-8656, Tokyo, Japan aut NATIONALLICENCE 700 1- Asai Kazumi Geoscience Laboratory Corporation, 1-608 Uedahonmachi, Tenpaku-ku, 468-0007, Nagoya, Japan aut NATIONALLICENCE 773 0- Hydrogeology Journal Springer-Verlag 19/1(2011-02-01), 249-258 1431-2174 19:1<249 2011 19 10040 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer