Phase transition and melting in zircon by nanosecond shock loading

• Published in: Physics and chemistry of minerals Vol. 49; no. 5
• Main Authors: Takagi, Sota, Ichiyanagi, Kouhei, Kyono, Atsushi, Kawai, Nobuaki, Nozawa, Shunsuke, Ozaki, Norimasa, Seto, Yusuke, Okuchi, Takuo, Nitta, Souma, Okada, Satoru, Miyanishi, Kohei, Sueda, Keiichi, Togashi, Tadashi, Yabuuchi, Toshinori
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-05-2022; Springer Nature B.V
• Subjects: Crystallography and Scattering Methods; Crystals; Decomposition; Earth and Environmental Science; Earth Sciences; Experimental and Analytical Techniques at Extreme and Ambient Conditions; Geochemistry; Lasers; Mineral Resources; Mineralogy; Original Paper; Phase transitions; Recrystallization; Scattering; Shock loading; Silicon dioxide; X-ray diffraction; Zircon; Zirconium dioxide; Zirconium silicate; Laser shock; Reidite; Melting; Zircon; In situ X-ray diffraction
• ISSN: 0342-1791; 1432-2021
• DOI: 10.1007/s00269-022-01184-8

In this study, we use laser-driven shock compression coupled with in situ X-ray diffraction to interrogate the phase transition dynamics of shock-compressed zircon (ZrSiO
4
) for the first time. A phase transition from zircon to the high-pressure reidite phase was observed during the nanosecond timescale of a laser-driven shock. At high laser power, diffraction peaks of zircon and reidite appeared superimposed on two broad features. This diffuse background was ascribed to liquid scattering from a partial melt. At the highest laser power, the diffuse scattering dominated, with minimal evidence for crystal diffraction. On release, the melt recrystallized into a combination of zircon and reidite. Decomposition of zircon to SiO
2
and ZrO
2
was not observed. This study revealed that on laser-shock timescales, the zircon–reidite phase transition readily occurs. However, the decomposition of zircon into ZrO
2
and SiO
2
is kinetically inhibited.