Aquifers Interaction in the Southwestern Foot of Mt. Fuji, Japan, Examined through Hydrochemistry and Statistical Analyses

• Gmati Sonia

  Sustainable Environmental Studies, Graduate School of Life and Environmental Sciences, University of Tsukuba

• Tase Norio

  Sustainable Environmental Studies, Graduate School of Life and Environmental Sciences, University of Tsukuba

• Tsujimura Maki

  Sustainable Environmental Studies, Graduate School of Life and Environmental Sciences, University of Tsukuba

• Tosaki Yuki

  Sustainable Environmental Studies, Graduate School of Life and Environmental Sciences, University of Tsukuba Now at Crustal Fluid Research Group, Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology

Abstract

Major ion chemistry, oxygen isotope and multivariate statistical method were used to investigate aquifers interaction in the southwestern foot of Mt. Fuji, the largest Quaternary stratovolcano in Japan. Groundwater samples were taken from different aquifers which are in descending order: the superficial aquifer, aquifers residing in the New Fuji Lava and the Old Fuji Aquifer. The geochemical signatures of groundwaters, notably the molar Na/Cl and Na/Ca ratios, oxygen stable isotope and the nitrate contents evolution, in conjunction with the hierarchical cluster analysis allowed to highlight three groundwater systems differing by their hydrochemical facies and residence time: 1) The shallow and highly polluted groundwaters of the superficial aquifer, 2) Groundwaters of the New Fuji Lava moderately mineralized and polluted, 3) The non-polluted groundwaters of the Old Fuji Aquifer. Waters of these systems are interacting. In fact, nitrate contamination, in provenance from the superficial aquifer, was detected in the New Fuji Lava layers and the deep groundwaters of the Old Fuji. Furthermore, many samples taken from the Old Fuji Aquifer were characterized by a relatively enriched δ¹⁸O. These results prove that groundwaters of the New Fuji layers could be mixed with groundwaters of the overlaying superficial aquifer and that these groundwaters, supposed to flow only horizontally, can flow vertically through the cracks, causing the mixing of deep and old groundwater of the Old Fuji with groundwaters recently recharged and polluted.<br>

Journal

• Hydrological Research Letters

  Hydrological Research Letters 5 58-63, 2011

  Japan Society of Hydrology and Water Resources (JSHWR) / Japanese Association of Groundwater Hydrology (JAGH) / Japanese Association of Hydrological Sciences (JAHS) / Japanese Society of Physical Hydrology (JSPH)

Keywords

• Earth and Planetary Sciences (miscellaneous)
• Water Science and Technology

Details

• CRID: 1390282680265283200
• NII Article ID: 130000954235
• DOI: 10.3178/hrl.5.58
• ISSN: 18823416
• Text Lang: en
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed