ON THE OBSERVATIONS OF THE ABRUPT CHANGE OF THE ELASTIC ENERGY IN THE CRUST IN THE REMARKABLE EARTHQUAKES

Abstract

We have sometimes found sudden changes of the crustal deformation in the observations with extensometers and tiltmeters. These changes are important phenomena to prove that earthquakes are the consequences of the changes of the elastic states in the crust. They are also important to study the mechanism of the earthquake. The present author has observed with extensometers the sudden changes of the crustal strains in the times of eleven earthquakes. These leaps on the observing extensions are comparable to the magnitudes of the respective earthquakes. Using these magnitudes of the leaps, he has calculated the quantities of the changes of elastic energy in the crust. And the azimuthal pattern of these leaps of strains in the times of earthquakes of Odaigahara, Kitamino and Off. Echizenmisaki.