A 4.5-magnitude earthquake rattled the Canterbury region just before 5.30pm on Sunday.
Striking 20 kilometres west of Christchurch, at a depth of seven kilometres, it was felt widely in the city, shaking buildings for five to 10 seconds.
There were also aftershocks in the Canterbury region on Sunday morning.
A 4.6 quake was recorded at 6.03am on Sunday, 30 kilometres south-east of Darfield. It was at a depth of five kilometres.
Other, smaller, tremors were recorded in the same area, and another near Lyttelton.
In the past week, the largest aftershocks were registered on Monday night and Tuesday morning, at a magnitude of 5.4.
GNS seismologist Brian Ferris says the chance of further aftershocks of this size are decreasing by the day.
Canterbury geologist Mark Quigley says magnitude-5 aftershocks are still possible. He says the largest aftershocks from other big earthquakes with similar characteristics have occurred seven or eight days after the main tremor.
Hundreds attend open air church service
Hundreds of people attended an open air church service in Christchurch's Cathedral Square.
Many churches across the region were damaged in last weekend's earthquake, prompting the mass gathering on Sunday for those who had nowhere else to worship.
About 500 people attended the service, in which the cathedral choir took part and the Anglican Bishop of Christchurch Victoria Matthews was among those who spoke.
The Dean of Christchurch, Peter Beck, told the congregation that the cathedral stood strong and firm, just like the people of Christchurch.
The cathedral was strengthened some years ago and after last weekend's earthquake engineers inspected the stonework of the historic building and found the cathedral in very good condition.
However a decision was made to close the cathedral until a full engineering report is completed this week.
Welfare centre residents relocated
The welfare centre at Linwood High School in Aranui closed on Sunday, to allow the school to reopen on Monday.
About 20 people relocated to a new shelter at Cowles Stadium, one of two welfare centres - along with Addington - which remain open.
About 40 people stayed at the Linwood centre on Saturday night.
Civil defence team in new HQ
The civil defence team is working out of the new Christchurch council building rather than the Christchurch Art Gallery, where it had been located since the magnitude -7.1 earthquake.
Christchurch mayor, Bob Parker, says the new council building suffered only superficial or easily reparable damage, but has taken a week to reopen because the aftershocks made it hard to do the work safely.
Mr Parker says the building performed as expected, and the only bolts that failed are ones which are designed to do so in an earthquake.
Regional Civil Defence controller John Mitchell says the state of emergency in the region will not be lifted until all agencies are ready to go into recovery mode.
He says at this stage all existing state of emergency declarations have been synchronised to end on Wednesday.
But Mr Mitchell says the state of emergency could be extended again if emergency services are not ready to enter the recovery phase by Wednesday.
Urban Search and Rescue teams are continuing to work in the city, stabilising buildings that are structurally unsound.
Up to 90 personnel are involved.
The Fire Service said by Sunday the teams had cleared more than 1600 homes and buildings since the quake.
More central city buildings were opening on Sunday and people were being encouraged to come back to shops and cafes. Several car park buildings are open and will be free to use this week.