Identifying and locating the geochemical and geophysical heterogeneities in the Earth’s interior is one of the most important and challenging tasks for the deep Earth scientists. Subducted oceanic crust metamorphizes into the dense eclogite in the upper mantle and is considered as a major cause of geochemical and geophysical heterogeneities in the deep Earth. In order to detect eclogitic materials inside the Earth, precise measurements of the high pressure‐temperature single‐crystal elasticity of major minerals in eclogite are thus exceedingly important. Omphacite, a Na,Al‐bearing clinopyroxene, constitutes up to 75 vol% of eclogite. In the present study, we performed the first high pressure‐temperature single‐crystal elasticity measurements of omphacite using Brillouin spectroscopy. Utilizing the finite‐strain approach, we obtained the following thermoelastic parameters for omphacite:
Compressional and shear wave velocities of topaz have been measured by ultrasonic interferometry in a multi‐anvil apparatus up to 13 GPa at room temperature. By fitting the measured velocities under pressure to finite strain equations, the elastic moduli of topaz and their pressure derivatives were obtained, yielding
- PAR ID:
- 10363039
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 49
- Issue:
- 2
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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