抄録
Major dacite pumice eruptions began at Usu Volcano on August 7, 1977. The relationship between the change in temperature of one of the associated hot springs and earthquake frequency of the volcano has been statistically examined using the data obtained from 1975 to the onset of the eruption. It is apparent that the coefficient of correlation between them markedly increased with time before the eruption. It may be a useful indicator to predict volcanic eruptions.