To understand global environmental changes, and the mechanisms causing these changes, it is necessary to evaluate quantitatively the cycling of subsurface materials. To achieve this goal, the Geochemical Research Group develops study of isotopic tracers from basic to frontier sciences (isotopes of Li, Sr, B, Pb, Mg, Ca, etc.).

Advanced research on isotope geochemistry

• Establishment of 'metal' isotopic tracers in carbonates to understand paleoenvironmental proxies.
• Elucidation of the presence and role of fluids within fault zones during co-seismic events.

Development of advanced techniques for isotope analysis

• Precise isotope analyses of non-radiogenic stable isotopes using a multiple collector ICP mass spectrometer and a thermal ionization mass spectrometer (Li, B, Mg, etc.).
• Precise isotope analysis of very small amount of Pb (<1ng) using an ICP mass spectrometer with multiple ion counting system.

Joint research and education

• Research and education in collaborative chair of Graduate School of Science, Hiroshima University.
• Understandings of environmental behavior of antimony on the basis of speciation and isotopic analyses (founded by Ministry of Environment 2008-2009, head: Dr. Y. Takahashi, Hiroshima University).
• Research of Oceanic Anoxic Events (OAE) and its paleo-environmental impact based on Pb isotope analysis of sediments (head: Dr. J. Kuroda, IFREE, JAMSTEC).

Joint research with Hiroshima University using a multiple collector ICP mass spectrometer.

Group Leader

Tsuyoshi Ishikawa

Sub Leader

Masaharu Tanimizu

Sub Leader

Motoo Ito

Sub Leader (add. post)

Hideaki Machiyama

Scientist

Yoshiro Nishio

Invited Principal Scientist

Yoshio Takahashi

 

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