2006 年 12 巻 23 号 p. 67-70
For an evaluation of seismic risk curve based on scenario earthquakes, the location, magnitude and occurrence frequency of all sources should be specified. However, it is difficult to specify hypocenters of crustal earthquakes without surface faults, because these are equally likely to occur anywhere over an area. One of the authors has proposed a method to deal with such earthquakes as scenario earthquakes, where it has some problems. In this paper, problems for the previous method are pointed out and an improved method is proposed. It is shown that the improved method has advantage of clarity in explanation as well as improved precision in evaluated values.