Routine observations of gravity changes have been performed at Kyoto, Japan and Bandung, Indonesia by employing superconducting gravimeters. Kyoto and Bandung are surrounded by the Pacific Ocean and other oceans. Gravity changes due to oceanic loading tides have a detectable signal level at each station. We can investigate viscosity of the crust and the upper mantle using differences between observed values and expected values of oceanic loading tides. Observed phase in the oceanic tidal

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... has a deviation about 10 degrees from the predicted phase in major parts of tidal constituents, though phase lag due to viscosity in the Earth is expected to be 0.1 degree or less.