[E] Oral
P (Space and Planetary Sciences )
» P-CG Complex & General
[P-CG22] Shock responses of planetary materials elucidated from meteorites and dynamic compression experiments
Tue. May 28, 2019 1:45 PM - 3:15 PM
A03 (TOKYO BAY MAKUHARI HALL)
convener:Toshimori Sekine(Center for High Pressure Science and Technology Advanced Research), Takuo Okuchi(Institute for Planetary Materials, Okayama University), Chairperson:Toshimori Sekine(HPSTAR & Osaka University), Ai-Cheng Zhang(Nanjing University)
Impact phenomena had played essential roles in the process of planetary evolution. Recent analytical and experimental developments reveal a new prospective on the effects of shock-compression process for planetary materials. For deeper understanding of such shock effects, it is necessary to evaluate the detailed shock conditions from the observations of naturally-shocked planetary materials, and to compare them with the results on the planetary materials experienced a wide range of known shock conditions. Several metastable phases, that have not been known before, have recently been identified in shocked meteorites. They suggest that the shock state is often not in equilibrium and that it is more complicated process than ever thought. Experimental techniques including laser-driven shock compression and x-ray free electron laser diagnostics have been progressed to successfully simulate a wide range of shock conditions. The recent results indicate that shocked grains are fractured and rotated at relatively low pressures, and that they are subsequently transformed into denser phases or melts, or their mixtures at pressures of a few 100s GPa. Understanding of such shock dynamics requires another prospect, which is qualitatively different from the static high pressure and high temperature consensus. Therefore, it is timely to have an international symposium on dynamics of planetary materials.
