Abstract
Two typhoons (T7916 and T7920) passed through the southern part of Kinki district in 1979. On these occasions, remarkable changes of ground-strains were observed with two components of laser extensometers which were installed in the underground tunnel of the Amagase Observatory. Assuming that the atmospheric perturbation caused by the passage of typhoon is a negative load acting on an elastic homogeneous and isotropic half-space, we calculated the change of strain-field around a cavity and compared it with observational results . As a result, observed values were one order larger than calculated ones. This suggests that observed ground-strains of the order of 10-7 at the time of the passage of typhoon were caused by the another source, for instance, the change of the water level of Amagase reservoir which exists near the observatory.
