Dual mode ultrasonic interferometry in multi-anvil high pressure apparatus using single-crystal olivine as the pressure standard

Abstract

Acoustic measurements of compressional (P) and shear (S) wave travel times were performed in a 1000-ton uniaxial split-cylinder apparatus (USCA-1000) of the Kawai-type up to 10 GPa at room temperature, using dual mode lithium niobate transducers and ultrasonic interferometry. The cell pressures were calibrated continuously by in-situ measurements of the travel times in a single crystal San-Carlos olivine buffer rod inside the cell assembly. Elastic compressional and shear wave velocities in a dense, fine-grained polycrystalline Al₂O₃ were measured simultaneously to 10 GPa; from these data, the elastic moduli and their pressure derivatives were obtained for the longitudinal modulus {L ₀ = 461(3) GPa, L ₀′ = 7.0(1)}, the shear modulus {G ₀ = 162(2) GPa, G ₀′ = 1.9(1)} and the bulk modulus {K ₀ = 245(3) GPa, K ₀′ = 4.5(1)}.

Acknowledgements

We would like to extend our gratitude to Dr. H. Spetzler for fruitful discussions on the bond and cable reverberation corrections. This paper was written while the corresponding author (RCL) was a visiting scientist in the CNRS laboratory of Jannick Ingrin and Olivier Jaoul at the Universite´ Paul Sabatier in Toulouse, France; he thanks them for their hospitality and support. These high-pressure experiments were conducted in the Stony Brook High Pressure Laboratory, which is jointly supported by Stony Brook University and the NSF Science and Technology Center for High Pressure Research (EAR-89-20239). This study was also supported by NSF grants to RCL (under EAR 96-14612 and 99-80491). MPI Publication No. 317.