特集：核―マントルの相互作用と共進化に関する研究の進展
地球型惑星核の物性と組成
2020 年 30 巻 2 号 p. 111-117
詳細
2020 年 30 巻 2 号 p. 111-117
To constrain the core compositions of terrestrial planets, sound velocity and density of liquid Fe-Ni-S and Fe-Ni-Si alloys were measured up to 14 GPa. Addition of S reduces the P-wave velocity and bulk modulus of liquid Fe-Ni while addition of Si rises the P-wave velocity and does not affect on the bulk modulus in the present pressure range. Based on the obtained elastic properties of liquid Fe-Ni-S and Fe-Ni-Si, the compositions of planetary cores are estimated by matching the planetary geodesy data to 3-7 wt%S or 7-14 wt%Si for Mercury and 30-34 wt%S or 28-33 wt%Si for Mars.
