1971 年 24 巻 3 号 p. 215-227
At what stage of earthquake phenomena is the total amount of energy to be liberated by a particular event determined? Is it scheduled since long before the occurrence of that event, just before its outbreak or just after termination of disturbance?
Through detailed study of the operation of a simulator treated in the first part of this paper, the author was led to be interested in the plausibilty of the last case.
The basic idea is that the elastic stress energy spread over vast volume of rock medium cannot be liberated at an instant but must be released as a result of sequential progression of rupture which may be controlled by numerous factors such as stress concentration strength, inhomogeneity, distribution of flaws etc. in the medium.
The implication is that the amount of energy which is going to be liberated by a particular earthquake can only be told on the probabilistic ground until all energy release processes of that event are brought to termination. The observed magnitude-frequency relations of earthquakes are in general agreement with this argument.