Jadeite in Chelyabinsk meteorite and the nature of an impact event on its parent body.
The Chelyabinsk asteroid impact is the second largest asteroid airburst in our recorded history. To prepare for a potential threat from asteroid impacts, it is important to understand the nature and formational history of Near-Earth Objects (NEOs) like Chelyabinsk asteroid. In orbital evolution of an asteroid, collision with other asteroids is a key process. Here, we show the existence of a high-pressure mineral jadeite in shock-melt veins of Chelyabinsk meteorite. Based on the mineral assemblage and calculated solidification time of the shock-melt veins, the equilibrium shock pressure and its duration were estimated to be at least 3-12 GPa and longer than 70 ms, respectively. This suggests that an impactor larger than 0.15-0.19 km in diameter collided with the Chelyabinsk parent body at a speed of at least 0.4-1.5 km/s. This impact might have separated the Chelyabinsk asteroid from its parent body and delivered it to the Earth.
Department of Earth Science, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan.
Shin
S
Ozawa
1] Department of Earth Science, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan [2] Department of Earth and Planetary Systems Science, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan.
Masaaki
M
Miyahara
1] Department of Earth Science, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan [2] V. S. Sobolev Institute of Geology and Mineralogy, SB RAS, Novosibirsk, 630090, Russia.
Eiji
E
Ohtani
Institute of Mineralogy, UB RAS, Miass, 456317, Russia.
Olga N
ON
Koroleva
Department of Earth Science, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan.
Yoshinori
Y
Ito
1] V. S. Sobolev Institute of Geology and Mineralogy, SB RAS, Novosibirsk, 630090, Russia [2] Novosibirsk State University, Novosibirsk, 630090, Russia.
Konstantin D
KD
Litasov
V. S. Sobolev Institute of Geology and Mineralogy, SB RAS, Novosibirsk, 630090, Russia.
Nikolay P
NP
Pokhilenko