Seismic activity in Christchurch rumbles on - seven years after two destructive earthquakes shook the region.
Since the 7.1-magnitude quake in September 2010 and a 6.3-magnitude quake in February 2011, the region has experienced more than 20,000 earthquakes and aftershocks, according to the Christchurch Quake Map.
Just last week the city was rocked by four quakes, ranging from 3.1 to 4.0.
GeoNet duty seismologist Anna Kaiser said this was typical behaviour for the Canterbury region and it would take years for seismic activity to return to its low pre-2010 rate.
"This week there's been a few quakes close to the central city and we get them further out as well. They're not a cause for concern,'' Ms Kaiser said.
"Since the quakes starting in 2010, there's been an increase in aftershocks - and we expect aftershocks every now and then.''
While aftershocks would continue, the chances of a large magnitude earthquake happening in the region had dropped off since the height of the earthquake sequence, Ms Kaiser said.
