[B-CG08] [EE] From Deep Sea to Deep Space: the Solar System Ocean World Exploration to Search for Life

[BCG08-03] Experimental study for better understanding of the high T-P water-rock interaction during oceanic impact of asteroids

*Manabu Nishizawa¹, Yohei Matsui¹, Takazo Shibuya¹, Konomi Suda¹, Ken Takai¹, Hajime Yano² (1.Japan Agency for Marine-Earth Science and Technology, 2.Japan Aerospace Exploration Agency for Space and Technology )

Keywords:oceanic impact, hadean, water-rock interaction

Chemical composition of the Hadean ocean would have affected prebiotic chemical evolution and subsequent metabolic evolution of early life. High temperature water-rock interaction during deep sea hydrothermal circulation would have been a key component determining the seawater chemistry in the Hadean. Further, water-rock interaction during oceanic impact of asteroids should have played a unique role in determining the chemical composition of the Hadean ocean because of i) much higher T-P condition of shock reaction than that of deep sea hydrothermal reaction and ii) the involvement in chemical reaction of undifferentiated asteroid materials that would have been absent in oceanic crust (e.g., metal iron). To better understand the role of high T-P water-rock interaction during oceanic impact on the early earth, we have newly established a methodology of experimental impact in an open system that can simulate the Pressure-Temperature path of oceanic impact most faithfully. In this meeting, we plan to report experimental results that rocky material impacted into liquid water at a velocity of 4-6 km/sec.