This paper attempts to improve the reliability of the TT method that is one of the estimation methods of an inland uplift rate based on the model in which riverbed elevation is controlled by the climate change and uplift. It is necessary for the TT method to distinguish fluvial terraces that formed in the marine isotope stage (MIS) 2 and 6, and therefore the flood loam and the phytolith are effective as indicators of the determination of emergence horizon of fluvial terrace and the estimation of paleoclimate, respectively. Furthermore, the identification of thick sediments suggesting the decline of tractive force in the glacial stage is useful for comparison and chronology of the terrace. We carried out the topographical and geological observations and analyses, and a seismic survey as examples around the Kaburagawa river and Tokigawa river to confirm these applicability. Though this study doesn't inspect a value of estimated uplift, it contributes to the reliability of the uplift evaluation by demonstrating the probability of the premise for the TT method based on synthetic terrace comparison and chronology.

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Bentonite will be used for a buffer material of radioactive waste disposal facilities in many countries of the world. For the operation of the facilities in the future, the stable supply of bentonite in the long term is necessary. When supply deficiency, quality change and soaring price of bentonite occur due to the demand growth, they would give adverse effects on the radioactive waste disposal project. In this paper, we studied the situation of bentonite production in the world, in particular in China. We also investigated analytical procedures and brief properties of Chinese, Japanese and American bentonite. As a result, however, we identified that the establishment of quality assurance systems for not only production but analytical procedures are necessary to assess evenly the suitability of each bentonite for radioactive waste disposal facilities.

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