Long-term Observation of Tidal Variations of in Situ Seismic Velocity and Attenuation

Abstract

The elastic stiffness of rocks near the earth's surface is expected to change by tidal stress variation. We conducted measurements of in situ compressional wave velocity and attenuation across a distance of 12 m at Aburatsubo, Japan. We detected the periodic variations in both velocity and attenuation, corresponding to the diurnal and semi-diurnal lunar and solar tides.