Skip to main content

Sound Velocities in Shock-Synthesized Stishovite to 72GPa

Author(s): Berryman, Eleanor J; Winey, JM; Gupta, Yogendra M; Duffy, Thomas S

To refer to this page use:
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.
Publication Date: 21-Nov-2019
Citation: Berryman, Eleanor J., J.M. Winey, Yogendra M. Gupta, and Thomas S. Duffy. "Sound Velocities in Shock‐Synthesized Stishovite to 72 GPa." Geophysical Research Letters 46, no. 23 (2019): 13695-13703. doi:10.1029/2019GL085301.
DOI: doi:10.1029/2019GL085301
ISSN: 0094-8276
EISSN: 1944-8007
Pages: 13695 - 13703
Type of Material: Journal Article
Journal/Proceeding Title: Geophysical Research Letters
Version: Final published version. Article is made available in OAR by the publisher's permission or policy.

Items in OAR@Princeton are protected by copyright, with all rights reserved, unless otherwise indicated.