S1, S4: Earth materials science related to igneous processes and plate convergence region (Joint Special Session)

[S1,S4-02] Depth profile of frictional properties inferred from cuttings obtained at the Nankai trough C0002 drilling site

*RIHO FUJIOKA¹, Katayama Ikuo¹, Kitamura Manami², Okuda Hanaya³, Hirose Takehiro⁴ (1. Hiroshima Univ. Sci., 2. AIST, 3. Univ. of Tokyo, AORI, 4. JAMSTEC Kochi Institute)

Keywords:Friction, Nanakai Trough, Accretionary prism, clay minerals

At drilling site C0002 of the NanTroSEIZE, cuttings samples have been continuously collected. In this study, frictional tests were carried out on these samples and the frictional properties-depth profiles were prepared and compared with the clay mineral content (Underwood 2017).Friction coefficient depend on depth, it may be related to the phase transition from smectite to illite.Velocity dependence of friction indicats velocity strengthening behavior. The frictional properties at Site C0002 are governed by the clay mineralogy and its content,and may be aseismic region.