Quantitative tracing of water-rock interactions by IR spectoroscopy; An Example of alkaline alteration of granitic rocks

Nakashima, Satoru*; Kirino, Yusuke*; Nishiyama, Naoki*; Tonoue, Ryota*; Yokoyama, Tadashi*; Nagasawa, Makoto*; Harui, Rika*; Walker, C.; Sasamoto, Hiroshi   

Cementitious grout material will be used to reduce groundwater inflow into the repository of high level radioactive waste. High pH solution derived from cementitious grout material may cause alteration of rock mass by grout-rock interactions. With regard to evaluation of radionuclide migration, it is important to evaluate the long-term behavior of rock mass affected by grout-rock interactions since such altered rock mass potentially affects on migration behavior (e.g., diffusion and sorption) of radionuclide. This study presents the results of identification for trace secondary minerals (alteration products) by (micro)infrared spectroscopy and determination of reaction rate constants of formation for secondary minerals.