A study of electirical properties and natural remanent magnetization of rhyolite

• Project/Area Number: 15K05342
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Petrology/Mineralogy/Economic geology
• Research Institution: Osaka University
• Principal Investigator: FUJI-TA Kiyoshi 大阪大学, 工学研究科, 教授 (00283862)
• Co-Investigator(Kenkyū-buntansha): 宇野 康司 岡山大学, 教育学研究科, 准教授 (10510745) ; 古川 邦之 愛知大学, 経営学部, 准教授 (20440620) ; 芳野 極 岡山大学, 惑星物質研究所, 准教授 (30423338)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2017: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2016: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2015: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
• Keywords: 電気伝導度 / 残留磁化 / 溶融 / ガラス転移点 / 流紋岩 / 安山岩 / 火山岩 / 部分溶融 / ガラス転移

Outline of Final Research Achievements

Natural volcanic rock contains various minerals and its conduction mechanism is complex. To comprehend the relationship between chemical components and electrical conductivity, we measured electrical conductivity of synthesized rhyolitic glass under high P-T conditions. Observed electrical conductivity change corresponds to glass transition (Tg) zone. As glass transition temperature is crucial to understand the upwelling mechanism of volcanic rock, we carefully observed the electrical conductivity changes of rhyolitic glass. We also observed the natural remanent magnetization direction of a thick rhyolite lava and investigated whether the rhyolite has the ability to record the expected remanent magnetization direction. Rhyolite lava showing significant deviation from the expected direction of the Earth's geomagnetic field was observed in part, while rhyolite lava samples mostly show similarity in the direction with the expected one.

Research Products

• [Journal Article] An analysis of apparent polar wander path for southwest Japan suggests no relative movement with respect to Eurasia during the Cretaceous (2017)
  • Author(s): Koji Uno, Kuniyuki Furukawa, Yuri Hatanaka
  • Journal Title: Physics of the Earth and Planetary Interiors Volume: 267 Pages: 19-30
  • Peer Reviewed
• [Journal Article] Tectonic evolution of the Malay Peninsula inferred from Jurassic to Cretaceous paleomagnetic results (2017)
  • Author(s): Yo-ichiro Otofuji, Yuji T. Moriyama, Maiko P. Arita, Masanari Miyazaki, Kosuke Tsumura, Yutaka Yoshimura, Mustaffa Kamal Shuib, Masatoshi Sone, Masako Miki, Koji Uno, Yutaka Wada, Haider Zaman
  • Journal Title: Journal of Asian Earth Sciences Volume: 134 Pages: 130-149
  • Peer Reviewed
• [Journal Article] 流紋岩・安山岩メルトの電気伝導度測定 (2016)
  • Author(s): 原口友輔, 芳野極, 山下茂, 藤田清士, 鈴木賢紀, 田中敏宏
  • Journal Title: CA研究会論文集 2016 Volume: - Pages: 12-19
• [Journal Article] 流紋岩・安山岩メルトの電気伝導度測定 (2016)
  • Author(s): 原口 友輔, 芳野 極, 山下 茂, 藤田 清士, 鈴木 賢紀, 田中 敏宏
  • Journal Title: Conductivity Anomaly 2015年 論文集 Volume: 印刷中
  • Acknowledgement Compliant
• [Presentation] Electrical conductivity measurement of rhyolitic and andesitic glasses (2017)
  • Author(s): Kiyoshi Fuji-ta, Y. Haraguchi, T. Yoshino, M. Suzuki, M. Nakamoto and T. Tanaka
  • Organizer: AGU Fall Meeting 2017
  • Int'l Joint Research
• [Presentation] Vertical Structural Variation and Their Development of the Sanukayama Rhyolite Lava in Kozushima Island, Japan (2017)
  • Author(s): Kuniyuki Furukawa, Koji Uno, Tatsuo Kanamaru, Kotaro Nakai
  • Organizer: AGU Fall Meeting 2017
  • Int'l Joint Research
• [Presentation] 流紋岩・安山岩メルトの電気伝導度測定 (2016)
  • Author(s): 原口 友輔, 芳野 極, 山下 茂, 藤田 清士, 鈴木 賢紀, 田中 敏宏
  • Organizer: 2015年Conductivity Anomaly研究集会
  • Place of Presentation: 東京大学地震研究所（東京都・文京区）
  • Year and Date: 2016-01-06