The quakes - including one of magnitude 6 and two above 5 on the Richter scale - damaged buildings, cut power, and caused mud and sewage to bubble into streets.
Several buildings which were partially demolished after previous quakes collapsed completely.
A spokesman for the St John ambulance service said they had received around 150 emergency calls. About 60 people were treated for minor injuries, heart attacks, panic attacks and collapses.
Thousands of shoppers were evacuated from malls, where goods tumbled from shelves on what should have been one of the busiest days of the year for retailers.
One woman customer said: “We saw the staff running out, so we thought if they are off, we’re going too.”
Frightened workers also ran out of office buildings across the city.
The international airport was closed for checks after the main terminal “shook violently", causing havoc for hundreds of passengers.
Residents in low-lying eastern suburbs were again hit hard by liquefaction, a process in which water oozes out of the ground, creating a tide of evil-smelling mud.
In hillside suburbs, the biggest danger came from rockfalls as loose boulders were dislodged.
Coastguard officials rescued four people who were trapped by a rockfall in Boulder Bay.
The energy supply company Orion was struggling to reconnect power to 26,000 properties.
Large pot-holes and cracks appeared in roads, which soon became gridlocked with traffic.
More than 7,000 aftershocks have rocked the city since a magnitude-7 quake struck on September 4, 2010.
A shallow 6.3 quake on Feb 22 this year killed 182 people and devastated the city centre business district, where ruined buildings are still cordoned off.
Many people were reduced to tears by the latest earthquakes, coming just as residents were daring to hope that the worst of the aftershocks were over.
John Key, the New Zealand Prime Minister, said the quakes were “frightening and disheartening” for residents.
"My heart goes out to the people of Christchurch and Canterbury at this time,” Mr Key said.
"However, residents can be confident that the authorities are on to the situation, and government resources stand ready to assist wherever they are needed.”
He pledged that his government’s resolve to rebuild the city remained unchanged.
Bob Parker, the mayor, interrupted a Christmas break in the North Island to head back to his city.
He said the shakes would take a large emotional toll on people.
"Many of them are just sitting around and in tears,” he said.