チリ津波による土地のひずみの観測

Abstract

The periodic variations of the ground-strains due to Chili tide wave in May 24, 1960 have been observed at Kishu (14.8 km away from the Pacific coast), Osakayama(65 km away from the Ise Bay) and Suhara (at sea-shore). According to the observa-tions except Suhara the ratio k of the amplitude of the strain due to the tsunami andthat of the semi-diurnal tide of it is very smaller than the ratio m of the amplitude ofthe tsunami and that of the semi-diurnal tide level at Kumano Sea. Using the valuesof k and m, the amplitude ratios of direct-effect due to the tidal force and the indirecteffect due to the oceanic tide in these three observatories are calculated. This resultshows that the indirect terms are negligible order at the observatories where is morethan 10km away from ocean.