2021 Annual Meeting of Japan Association of Mineralogical Sciences (JAMS)
Sep 15 - Sep 19, 2021Online
2021 Annual Meeting of Japan Association of Mineralogical Sciences (JAMS)
Sep 15 - Sep 19, 2021Online
[R3-02]Rheological weakening induced by the olivine-ringwoodite transformation[Presentation award entry]
*Rikuto Honda1, Tomoaki Kubo1, Yuichiro Mori2, Yuta Goto1, Takuya Iwasato3, Yuji Higo4, Masaaki Miyahara5(1. Kyushu Univ., 2. U. Tokyo, 3. Shin-Nippon Nondestructive Inspection Co., Ltd., 4. JASRI, 5. Hiroshima Univ.)
Keywords:
slab weakening,deep earthquake,transformation,in-situ X-ray observation,acoustic emission
To investigate Rheological Weakening and Shear Instability in deep slabs, we carried out the olivine (ol) - ringwoodite (rw) transformation experiments under uniaxial stress at 10-20GPa, 723-1273K, using a D111-type apparatus combined with X-ray and AE measurement system. We observed that the strength of Rw newly transformed was very small compared to that of parental Ol (~10-20%) at large overpressure and low T conditions. The parental Ol also rheologically weakens as the transformation proceeds probably because the fine grained weak Rw is interconnected.