An investigation of the frequency/magnitude distribution of earthquakes

Abstract

The evaluation of the parameters a, b in the frequency/magnitude relation log(n) = a - b.M for earthquakes, although usually effected by the maximum likelihood method alone, can be improved by using the least-squares method to recognise and remove bias due to inadequacies in the data. This is demonstrated with reference to the catalogue of shallow earthquakes in the New Zealand region for the fifteen year period of 1964 - 1978.