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

[S1,S4-04] Relationship between hydrothermal fluid-induced illite and void, and faulting process

*Jun-ichi Ando¹, Kouta Kojima¹, Kaushik DAS¹, Naotaka Tomioka², Seiichiro Uehara³ (1. Hiroshima Uni., 2. JAMSTEC・Kochi Core Center, 3. Kyushu Univ.)

Keywords:Illite, Fluid, Fault, stylolite

Hydrothermal fluid is thought to have a significant influence on the faulting process. Based on the geological survey and microstructural observation of rocks, we report the possibility that the crystallization of illite and the formation of vacancies caused by hydrothermal fluid contributed significantly to the fault formation developed in massive chert block. The key phenomenon in this study is the formation of a stylolite seam.