抄録
Calcite, which is a universal mineral in meteorites and rocky planet surfaces, might be a source of CO
and/or CO2 gas components caused by impact processes. In this study, we conducted Hugoniot measurements
and in-situ XRD (x-ray diffraction) observations of calcite during shock processes in order to
understand shock responses and shock-induced reactions under planetary impact conditions. We newly
obtained experimental data of shocked calcite above 100 GPa using a high-power laser shock technique.
Our temperature data indicated a large difference from the previous theoretical model as well as some
state changes along the Hugoniot. The result of the in-situ XRD observations using an X-ray Free
Electron Laser (XFEL) shows the polycrystallization and the melting of calcite during the compressed
and released state. Such shock-induced reactions of calcite may affect the estimation of the total energy,
the thermal history and the degassing chemical species during planetary impacts.
