A statistical survey of earthquakes in the main seismic region of New Zealand

Abstract

Maps are presented showing contours of frequency of earthquake occurrence in the main seismic region of New Zealand from 1942 to 1961. Shallow, intermediate, and deep earthquakes are considered separately; the deeper earthquakes have a more regular and concentrated distribution, and their highest concentration is to the north-west of that of the shallower shocks. Close relationships between the patterns of seismicity and isostatic gravity anomalies are not apparent.