Christchurch City Council has told residents the area is likely to experience more magnitude five or six earthquakes during the coming month, but larger earthquakes are likely to be further away from the city, causing less damage.

The council has been briefed by scientists who say the  latest earthquakes which have been occurring off the coast in Pegasus Bay are also unlikely to produce a large earthquake of magnitude seven, resulting in any life-threatening tsunami.

GNS Science and Tonkin and Taylor experts addressed a meeting of the city’s elected members, local Members of Parliament and media, a meeting called by Mayor Bob Parker following the latest aftershocks which began on December 23.

GNS Science Earthquake scientist Kelvin Berryman said their expectation is that the current sequence of earthquakes will start to decrease over the coming months.

“Certainly we believe that a lot of the stress has already been released on the fault lines closer to the city. We believe we are progressing into a period similar to after the February and June 2011 earthquakes. They will go on for some time but they will become undetectable over time.”

He also said the risk of tsunami had not changed as a result of the recent earthquakes.

“From the information we have, a local source tsunami from an earthquake fault in Pegasus Bay is thought to be unlikely.”

Other key points made at the briefing include:

• the magnitude 6.0 earthquake that occurred on December 23 was only slightly above what scientists had predicted. Scientists have previously said that there was a 50 per cent  chance of a magnitude 5-5.9 earthquake occurring in the coming year;

• the probability of a magnitude 7.0 earthquake is low;

• the peak ground acceleration (a measurement of how hard the ground shakes) is decreasing and the peak ground acceleration during the December 23  aftershocks was less than the June 13 aftershocks and significantly lower than that experienced during the February 22 earthquake, which caused significant building and ground damage;

• it is difficult to predict how long the region will continue to experience earthquakes but it could last for up to several decades; however, they will become undetectable except on sensitive instruments over time.