@article{6922cdd003cd46dfac0d4708fefb916f,
title = "Sound Velocities in Shock-Synthesized Stishovite to 72 GPa",
abstract = "Stishovite (rutile-type SiO2) is the archetype of dense silicates and may occur in postgarnet eclogitic rocks at lower-mantle conditions. Sound velocities in stishovite are fundamental to understanding its mechanical and thermodynamic behavior at high pressure and temperature. Here, we use plate-impact experiments combined with velocity interferometry to determine the stress, density, and longitudinal sound speed in stishovite formed during shock compression of fused silica at 44 GPa and above. The measured sound speeds range from 12.3(8) km/s at 43.8(8) GPa to 9.8(4) km/s at 72.7(11) GPa. The decrease observed at 64 GPa reflects a decrease in the shear modulus of stishovite, likely due to the onset of melting. By 72 GPa, the measured sound speed agrees with the theoretical bulk sound speed indicating loss of all shear stiffness due to complete melting. Our sound velocity results provide direct evidence for shock-induced melting, in agreement with previous pyrometry data.",
keywords = "fused silica, melting, plate impact, shock, sound speed, stishovite",
author = "Berryman, {Eleanor J.} and Winey, {J. M.} and Gupta, {Yogendra M.} and Duffy, {Thomas S.}",
note = "Funding Information: The authors are grateful for the support of Y. Toyoda, N. Arganbright, and K. Zimmerman (Washington State University) in carrying out the experiments and to S. J. Tracy (Carnegie Institution for Science) for insightful discussion. The final manuscript benefitted from the thoughtful input of two anonymous reviewers. The work is supported by the DOE/NNSA under Cooperative Agreement DE‐NA0002007. supporting information Additional experimental parameters and details of data extraction are available in the . Data from this work is archived in the Department of Geosciences community of Princeton University's DataSpace: http://arks.princeton.edu/ark:/88435/dsp01mw22v8352 . Funding Information: The authors are grateful for the support of Y. Toyoda, N. Arganbright, and K. Zimmerman (Washington State University) in carrying out the experiments and to S.?J. Tracy (Carnegie Institution for Science) for insightful discussion. The final manuscript benefitted from the thoughtful input of two anonymous reviewers. The work is supported by the DOE/NNSA under Cooperative Agreement DE-NA0002007. Additional experimental parameters and details of data extraction are available in the supporting information. Data from this work is archived in the Department of Geosciences community of Princeton University's DataSpace: http://arks.princeton.edu/ark:/88435/dsp01mw22v8352. Publisher Copyright: {\textcopyright}2019. American Geophysical Union. All Rights Reserved.",
year = "2019",
month = dec,
day = "16",
doi = "10.1029/2019GL085301",
language = "English (US)",
volume = "46",
pages = "13695--13703",
journal = "Geophysical Research Letters",
issn = "0094-8276",
publisher = "American Geophysical Union",
number = "23",
}