Japan Geoscience Union Meeting 2018

Presentation information

[JJ] Oral

B (Biogeosciences) » B-CG Complex & General

[B-CG09] Decoding the history of Earth: From Hadean to the present

Mon. May 21, 2018 3:30 PM - 5:00 PM Convention Hall B (CH-B) (2F International Conference Hall, Makuhari Messe)

convener:Tsuyoshi Komiya(Department of Earth Science & Astronomy Graduate School of Arts and Sciences The University of Tokyo), Yasuhiro Kato(Department of Systems Innovation, Graduate School of Engineering, University of Tokyo), Katsuhiko Suzuki(国立研究開発法人海洋研究開発機構・海底資源研究開発センター), Chairperson:Komiya Tsuyoshi

3:45 PM - 4:00 PM

[BCG09-02] The roles of hypervelocity impacts on the surface evolution of the Hadean Earth

★Invited Papers

*Kosuke Kurosawa1, Takaya Okamoto1, Hikaru Yabuta2, Goro Komatsu3, Takafumi Matsui1 (1.Planetary Exploration Research Center, Chiba Institute of Technology, 2.Dept. Earth and Planet. Sys. Science, Hiroshima University, 3.International Research School of Planetary Sciences, Università d'Annunzio)

Keywords:Hypervelocity imapcts, Post-impact chemistry, Two-stage hydrogen gas gun, In-situ gas phase analysis, Quadrupole mass spectrometer

Impact bombardments are the main driving forces of the surface evolution on the Hadean Earth. Typical impact velocity onto the Earth is estimated to become 20 km/s, resulting in an extremely-high energy density to be about 200 MJ/kg. The energy density corresponds to a temperature and pressure of 200000 K and 600 GPa, respectively. Thus, hypervelocity impacts would cause physical/chemical processes, which is never driven under the mean field on the Hadean Earth, resulting in an intense and impulsive catastrophic perturbation. Chemical products produced by such high-energy collisions might be fixed into ancient stratifications as unique chemical features. We are constructing a new experimental system at Planetary Exploration Research Center of Chiba Institute of Technology to understand the roles of impact-driven chemical processes on the surface environment on the Hadean Earth. In the presentation, we will present a brief review about the thermodynamics behind the impact-driven processes and will discuss a future plan induced by the new experimental system.