According to GNS Science, Canterbury has experienced 270 reverberations of magnitude 3 or more from Saturday's earthquake. Seismologist Brian Ferris said that the people would have received around 150 of these aftershocks.
He said that while 10 aftershocks were between magnitude 5 and 5.5, 60 were between 4 and 4.9, and 200 were between 3 and 3.9. And from midnight there have been 18 reverberations.
Dr. John Townend from Victoria University said that if they take into account the magnitude of the quake, the number of aftershocks was not shocking. He said, "This is what big earthquakes do. They cause aftershocks and they do rattle on for some time so nerves will be frayed".
It is reported that a 5.1 magnitude aftershock created panic in Christchurch that took place before 8am today. The aftershock was 6km deep and affected the city's port region of Lyttelton. It is speculated that Christchurch might witness another big aftershock.
Dr. Townend is of the opinion that though there is a likelihood that the quakes might go on for some weeks, they would decrease in intensity.
He said that with an earthquake that has a 7.1 magnitude, you are liable to receive aftershocks as big as one unit lesser that is magnitude 6.1