My research focuses on the viscoelastic properties, especially anelasticity, of polycrystalline materials. Rock anelasticity causes dispersion and attenuation of seismic waves. In order to interpret the seismic structures in the Earth, it is important to understand the effects of temperature, grain size, melt fraction, and dislocation density on rock anelasticity. For this purpose, I have so far taken experimental approaches to measure viscoelastic properties using rock’s “analogue” materials. At Univ. Tokyo in Japan, I used organic polycrystals and mainly studied the effects of temperature and partial melting on anelasticity. Here at Lamont, I am using ice polycrystals to investigate the effects of dislocations on anelasticity. Taking advantage of the analogue experiments, I attempt to understand the underlying physical processes common to general polycrystals including rock.