Distribution of frictional heating temperature of fault surface estimated by carbonaceous material Raman geothermometer

• Project/Area Number: 15K21177
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Geology; Solid earth and planetary physics
• Research Institution: Shimane University
• Principal Investigator: Mukoyoshi Hidki 島根大学, 総合理工学研究科, 助教 (80744200)
• Research Collaborator: Hirono Tetsuro ; Ikehara Minoru
• Project Period (FY): 2015-04-01 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000); Fiscal Year 2016: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2015: ¥2,990,000 (Direct Cost: ¥2,300,000、Indirect Cost: ¥690,000)
• Keywords: ラマン分析 / 断層 / 摩擦発熱 / 付加体 / 炭質物 / 熱熟成

Outline of Final Research Achievements

We performed microstructural observation and Raman spectroscopic analyses of carbonaceous materials (CM) in the fault rock of 2.5-5.5 km depth of an ancient megasplay fault (an outof sequence thrust in the Shimant accretionary complex) and 14 km depth of a thrust in the Emi group, Hota accretionary complex, exposed on Japan. We also conducted heating experiment of CM in host rock of these fault with anaerobic condition (range:100-1300℃, intervals: 100℃, rate of temperature increase: 20 K/min) in order to investigate the effects of fast heating rate like frictional heating during earthquake.
Raman spectrum of CM of both fault is similar to spectrum of 400-600℃ heating experiment of CM. This result shows that both fault had heating history of 400-600 ℃ by frictional heating. To evaluate the levels of friction, Raman spectrum of the short time maturated experimented CM is useful as calibration tool.

Research Products

• [Journal Article] Organochemical characteristics of carbonaceous materials as indicators of heat recorded on an ancient plate-subduction fault (2016)
  • Author(s): Kaneki, S., Hirono, T., Mukoyoshi, H., Sampei, Y., Ikehara, M
  • Journal Title: Geochemistry, Geophysics and Geosystem Volume: 17 Issue: 7 Pages: 2855-2868
  • DOI: 10.1002/2016gc006368
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] 陸上付加体から明らかとなった沈み込みプレート境界断層の断層岩の特徴 (2016)
  • Author(s): 向吉秀樹
  • Journal Title: 島根県地学会誌 Volume: 31 Pages: 3-7
• [Journal Article] 陸上付加体研究から明らかとなった沈み込みプレート境界型断層の断層岩の特徴 (2016)
  • Author(s): 向吉秀樹
  • Journal Title: 島根県地学会会誌 Volume: 31 Pages: 3-7
• [Presentation] Maturation during short-duration heating of carbonaceous material: A new indicator for frictional heat during earthquake slip (2016)
  • Author(s): Mukoyoshi, H., Hirono, T
  • Organizer: American Geophysical Union (AGU) 2016 Fall Meeting
  • Place of Presentation: サンフランシスコ
  • Int'l Joint Research
• [Presentation] 断層摩擦発熱に伴う炭質物熟成の特徴：断層岩中の炭質物のラマン分析より (2015)
  • Author(s): 向吉秀樹・廣野哲朗
  • Organizer: 日本地球惑星科学連合 連合大会 2015年大会
  • Place of Presentation: 幕張メッセ
  • Year and Date: 2015-05-24
• [Remarks]
  • URL: http://www.geo.shimane-u.ac.jp/mukoyoshi/study.htm