Technical development of sound velocity and density measurements of liquid iron alloys up to Martian core conditions

• Project/Area Number: 26800231
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Solid earth and planetary physics
• Research Institution: The University of Tokyo
• Principal Investigator: Nishida Keisuke 東京大学, 大学院理学系研究科(理学部), 助教 (40530887)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000); Fiscal Year 2016: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2015: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2014: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
• Keywords: 火星核 / 月核 / 液体 / 音速 / 高温高圧 / 鉄合金 / 地球核 / 密度 / 水星核 / メルト

Outline of Final Research Achievements

We set up an in-situ sound velocity measurements system using ultrasonic pulse echo method combined with synchrotron X-ray technique and Kawai-type multi-anvil apparatus at AR-NE7A beamline of KEK PF. We conducted additional experiments and reanalyses of previous data to solve the discrepancy among the sound velocities in liquid Fe-S reported by different research groups. We proposed new density and velocity model of the Moon's core.
We developed techniques to measure sound velocity in liquid Fe alloys up to 20 GPa. The size and materials of parts of high-pressure cell were optimized to maintain parallel between the front and back surfaces of the sample at high pressure and high temperature. We developed an ultrasonic transducer with high-sensitivity and broad bandwidth. We successfully measured sound velocity in liquid Fe80S20 up to 20 GPa with an error of 1% at the best, and with an error of 2.5% even at the highest pressure.

Research Products

• [Journal Article] Towards a consensus on the pressure and composition dependence of sound velocity in the liquid Fe-S system (2016)
  • Author(s): K. Nishida, A. Suzuki, H. Terasaki, Y. Shibazaki, Y. Higo, S. Kuwabara, Y. Shimoyama, M. Sakurai, M. Ushioda, E. Takahashi, T. Kikegawa, D. Wakabayashi, and N. Funamori
  • Journal Title: Physics of the Earth and Planetary Interiors Volume: 257 Pages: 230-239
  • DOI: 10.1016/j.pepi.2016.06.009
  • Peer Reviewed / Open Access
• [Journal Article] Compressional and shear wave velocities for polycrystalline bcc-Fe up to 6.3 GPa and 800 K (2016)
  • Author(s): Y. Shibazaki, K. Nishida, Y. Higo, M Igarashi, M. Tahara, T. Sakamaki, H. Terasaki, Y. Shimoyama, S. Kuwabara, Y. Takubo, E. Ohtani
  • Journal Title: American mineralogist Volume: 101 Issue: 5 Pages: 1150-1160
  • DOI: 10.2138/am-2016-5545
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Sound velocity and elastic properties of Fe-Ni and Fe-Ni-C liquids at high pressure (2016)
  • Author(s): Soma Kuwabara, Hidenori Terasaki, Keisuke Nishida, Yuta Shimoyama, Yusaku Takubo, Yuji Higo, Yuki Shibazaki, Satoru Urakawa, Kentaro Uesugi, Akihisa Takeuchi, Tadashi Kondo
  • Journal Title: Physics and Chemistry of Minerals Volume: 43 Issue: 3 Pages: 229-236
  • DOI: 10.1007/s00269-015-0789-y
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Repulsive Nature for Hydrogen Incorporation to Fe₃C up to 14 GPa (2014)
  • Author(s): Terasaki H., Shibazaki Y., Nishida K., Tateyama R., Takahashi S., Ishii M., Shimoyama Y., Ohtani E., Funakoshi K., Higo Y.
  • Journal Title: ISIJ International Volume: 54 Issue: 11 Pages: 2637-2642
  • DOI: 10.2355/isijinternational.54.2637
  • NAID: 130004705014
  • ISSN: 0915-1559, 1347-5460
  • Peer Reviewed / Open Access
• [Journal Article] High-pressure and high-temperature phase diagram for Fe0.9Ni0.1-Halloy (2014)
  • Author(s): Shibazaki Y., Terasaki H., Ohtani E., Tateyama R., Nishida K., Funakoshi K., Higo Y.
  • Journal Title: Physics of the Earth and Planetary Interiors Volume: 228 Pages: 192-201
  • DOI: 10.1016/j.pepi.2013.12.013
  • Peer Reviewed
• [Presentation] 高温高圧下におけるFe-S メルトの音速測定 (2017)
  • Author(s): 西田圭佑、柴崎裕樹、戸邉宙、阿部涼太、若林大佑、船守展正、 寺崎英紀、肥後祐司、鈴木昭夫
  • Organizer: 2016年度量子ビームサイエンスフェスタ
  • Place of Presentation: つくば国際会議場（茨城県つくば市）
  • Year and Date: 2017-03-14
• [Presentation] 20 GPa までのFe-S 系メルトの音速測定 (2016)
  • Author(s): 西田圭佑、柴崎裕樹、戸邉宙、阿部涼太、若林大佑、船守展正、寺崎英紀、肥後祐司、 鈴木昭夫
  • Organizer: 第57回高圧討論会
  • Place of Presentation: 筑波大学大学会館（茨城県つくば市）
  • Year and Date: 2016-10-26
• [Presentation] Technical development and improvement for sound velocity measurements of liquid Fe-S up to 15 GPa using ultrasonic pulse-echo method (2016)
  • Author(s): K. Nishida, A. Suzuki, Y. Shibazaki, D. Wakabayashi, N. Funamori
  • Organizer: 日本地球惑星連合2016年度大会
  • Place of Presentation: 幕張メッセ（千葉県幕張市）
  • Year and Date: 2016-05-22
  • Int'l Joint Research
• [Presentation] 20 GPa までのFe-S 系メルトの音速測定手法の開発 (2016)
  • Author(s): 西田圭佑
  • Organizer: 第３回愛媛大学先進超高圧科学研究拠点（PRIUS）シンポジウム
  • Place of Presentation: 愛媛大学（愛媛県松山市）
  • Year and Date: 2016-02-23
• [Presentation] The effects of pressure and alloying Ni and C on sound velocity of liquid Fe-alloys (2015)
  • Author(s): H. Terasaki, S. Kuwabara, K. Nishida, Y. Shimoyama, Y. Takubo, Y. Higo, Y. Shibazaki, S. Urakawa, T. Kondo
  • Organizer: American Geophysical Union Fall Meeting
  • Place of Presentation: San Francisco (USA)
  • Year and Date: 2015-12-14
  • Int'l Joint Research
• [Presentation] Fe-NiおよびFe-Ni-C 融体の音速の圧力依存性 (2015)
  • Author(s): 寺崎英紀，桑原荘馬，下山裕太，西田圭佑，肥後祐司，田窪勇作，柴崎裕樹，浦川啓，近藤忠
  • Organizer: 第56回高圧討論会
  • Place of Presentation: JMSアステールプラザ（広島県広島市）
  • Year and Date: 2015-11-10
• [Presentation] The effect of Ni and C on sound velocity of liquid Fe at high pressure (2015)
  • Author(s): S. Kuwabara, H. Terasaki, Y. Shimoyama, K. Nishida, Y. Higo, Y. Takubo, Y. Shibazaki, M. Tahara, M. Igarashi, T. Sakamaki, Y. Tange, T. Kondo
  • Organizer: 日本地球惑星連合2015年度大会
  • Place of Presentation: 幕張メッセ（千葉県幕張市）
  • Year and Date: 2015-05-24
• [Presentation] Sound velocity and density of liquid Fe-Ni-Si under pressure: Ap4plication to the composition of planetary molten core (2014)
  • Author(s): Hidenori Terasaki, Soma Kuwabara, Yuta Shimoyama, Yusaku Takubo, Satoru Urakawa, Keisuke Nishida, Akihisa Takeuchi, Yoshio Suzuki, Kentaro Uesugi, Tetsu Watanuki, Yoshinori Katayama, Tadashi Kondo, Yuji Higo
  • Organizer: AGU Fall Meeting
  • Place of Presentation: サンフランシスコ（アメリカ）
  • Year and Date: 2014-12-15
• [Presentation] PF AR-NE7Aでの高圧下における弾性波速度測定 (2014)
  • Author(s): 西田圭佑、鈴木昭夫、若林大佑、柴崎裕樹、亀卦川卓美、船守展正
  • Organizer: 第55回高圧討論会
  • Place of Presentation: 徳島大学常三島キャンパス（徳島県）
  • Year and Date: 2014-11-23
• [Presentation] 高圧下その場X線小角散乱による相転移中間状態の観察 (2014)
  • Author(s): 佐藤友子、若林大佑、西田圭佑、横井雄行、亀卦川卓美、船守展正
  • Organizer: 第55回高圧討論会
  • Place of Presentation: 徳島大学常三島キャンパス（徳島県）
  • Year and Date: 2014-11-23
• [Presentation] X線小角散乱で見る高圧力下のイオン液体の構造変化 (2014)
  • Author(s): 浜谷望、高久真由美、山村実早保、若林大佑、西田圭佑、船守展正、佐藤友子、亀卦川卓美、阿部洋、吉村幸浩
  • Organizer: 第55回高圧討論会
  • Place of Presentation: 徳島大学常三島キャンパス（徳島県）
  • Year and Date: 2014-11-23
  • Invited
• [Presentation] 超音波法およびX線CTを用いた高圧下におけるFe-Ni-C及びFe-Ni融体の音速・密度の同時測定 (2014)
  • Author(s): 桑原荘馬、寺崎英紀、西田圭佑、下山裕太、肥後祐司、田窪勇作、浦川啓、鈴木芳生、竹内晃久、上杉健太朗、近藤忠
  • Organizer: 第55回高圧討論会
  • Place of Presentation: 徳島大学常三島キャンパス（徳島県）
  • Year and Date: 2014-11-22
• [Presentation] Relationship between sound velocity and density of liquid alloy under pressure (2014)
  • Author(s): 寺崎英紀、西田圭佑、浦川啓、桑原荘馬、田窪勇作、下山裕太、上杉健太朗、竹内晃久、 鈴木芳生、河野義生、肥後祐司、近藤忠
  • Organizer: 日本地球惑星科学連合2014年大会
  • Place of Presentation: パシフィコ横浜（神奈川県）
  • Year and Date: 2014-04-29