JpGU-AGU Joint Meeting 2017

Presentation information

[JJ] Oral

S (Solid Earth Sciences) » S-SS Seismology

[S-SS17] [JJ] Fault Rheology and Earthquake Physics

Sat. May 20, 2017 1:45 PM - 3:15 PM A09 (Tokyo Bay Makuhari Hall)

convener:Takanori Matsuzawa(National Research Institute for Earth Science and Disaster Resilience), Takeshi Iinuma(National Research and Development Agency Japan Agency for Marine-Earth Science and Technology), Wataru Tanikawa(Japan Agency for Marine-Earth Science and Technology, Kochi Instutute for Core Sample Research), Hideki Mukoyoshi(Department of Geoscience Interdisciplinary Graduate School of Science and Engineering, Shimane University), Chairperson:Takeshi Iinuma(National Research and Development Agency Japan Agency for Marine-Earth Science and Technology), Chairperson:Tetsuro Hirono(Department of Earth and Space Science, Graduate School of Science, Osaka University)

2:30 PM - 2:45 PM

[SSS17-10] Experimental measurements and numerical analyses about the temperature change of rocks with stress chang

*Xiaoqiu Yang1, Weiren Lin2,3, Osamu Tadai4, Xin Zeng1 (1.South China Sea Institute of Oceanology, Chinese Academy of Sciences, 2.Graduate School of Engineering, Kyoto University, 3.Kochi Institute for Core Sample Research, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 4.Marine Works Japan Ltd.)

Keywords:Adiabatic pressure derivative of temperature (β), Temperature response, Stress change, Hydrostatic compression system, Numerical simulating

The temperature responses of rocks to stress changes are key to understanding temperature anomalies in geoscience phenomena such as earthquakes. We developed a new hydrostatic compression system in which the rock specimen center can achieve adiabatic conditions during the first ~10 s following rapid loading or unloading, and systematically measured the representative lithologies of several sedimentary, igneous and metamorphic rocks sampled from two seismogenic zones (the Longmenshan Fault Zone in Sichuan, and the Chelungpu Fault Zone (TCDP Hole-A) in Taiwan), and several quarries worldwide. And we built a finite element model of heat conduction to confirm the measured results of temperature response of rocks to stress change. The results show that: (1) the adiabatic pressure derivative of the temperature (β) for most crustal rocks is ~1.5 to 6.2 mK MPa-1, (2) the temperature response of sedimentary rocks (~3.5 to 6.2 mK MPa-1) is larger than that of igneous and metamorphic rocks (~2.5 to 3.2 mK MPa-1), and (3) there is a good linear correlation between β (in mK MPa-1) and the bulk modulus K (in GPa): β=(-0.068·K+5.69)±0.4, R2=0.85. This empirical equation will be very useful for estimating the distribution of β in the crust, since K can be calculated when profiles of crustal density (ρ) and elastic wave velocities (Vp, Vs) are obtained from gravity surveys and seismic exploration.