Sound velocity and density measurements of liquid Fe-Ni-S alloys at high pressure

2017 Fiscal Year Final Research Report

• Project/Area Number: 16K17799
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Solid earth and planetary physics
• Research Institution: Japan Synchrotron Radiation Research Institute
• Principal Investigator: Saori Kawaguchi 公益財団法人高輝度光科学研究センター, 利用研究促進部門, 研究員 (00773011)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Keywords: 地球外核組成 / 高圧実験 / ダイヤモンドアンビルセル / X線非弾性散乱 / X線全散乱 / 弾性波速度 / 密度 / 液体鉄合金

Outline of Final Research Achievements

The Earth’s outer core is mainly constructed of Fe-Ni alloys with around 10% light element(s) such as H, C, N, O, SI, and S. Both the nature and the amount of core light elements have been left as one of the biggest enigma of the Earth science for more than 60 years. The seismic wave traveled through the Earth’s interior is the first order information to know it, therefore, it is a valid method to directly compare with the measured sound velocity in DAC and seismic observation. Here, we focused on sulfur as a possible candidate for lighter component in the Earth’s outer core, and investigated the sound velocity and density of liquid Fe-Ni-S alloys with using high-resolution inelastic X-ray scattering spectroscopy method and X-ray total scattering measurements using diamond anvil cells at high pressure and temperature corresponding to the Earth's outer core at SPring-8.

Free Research Field

地球惑星科学