Simultaneous Determination of Elastic Constants and Asphericity of Spherical Specimens by the Resonant Sphere Technique.

A method is developed to simultaneously determine both the elastic constants and asphericity of a spherical specimen by the resonant sphere technique (RST). First, a numerical test is presented to examine the possibility of simultaneous determination of the specimen's elastic constants and asphericity by an inversion analysis of the resonant frequencies measured for the specimen. Then, the method is applied to elasticity measurements of a spherical olivine specimen with small asphericity. The simultaneous inversion analysis method allows one to evaluate elastic constants and asphericity more accurately than the previous method, in which the asphericity and elastic properties are separately determined. Since the asphericity of a spherical specimen has a noticeable influence on the calculated elastic constants, simultaneous inversion is an effective method to obtain improvements in the accuracy of the elastic constants and to quantify the asphericity of the specimen by the RST.