Date | 4 September 2010 |
---|---|
Origin time | 04:35 NZST |
Magnitude | 7.1 Mw |
Depth | 10 km (6.2 mi) |
Epicenter |
43°33′S 172°11′E / 43.55°S 172.18°ECoordinates: 43°33′S 172°11′E / 43.55°S 172.18°E near Darfield, Canterbury |
Areas affected | New Zealand |
Max. intensity | X (Extreme) |
Peak acceleration | 1.26 g |
Aftershocks | ~17,600 (as of early August 2016) |
Casualties | 2 seriously injured, approximately 100 total injuries |
The 2010 Canterbury earthquake (also known as the Darfield earthquake) struck the South Island of New Zealand with a moment magnitude of 7.1 at 4:35 a.m. local time on 4 September, and had a maximum perceived intensity of X (Extreme) on the Mercalli intensity scale. Some damaging aftershocks followed the main event, the strongest of which was a magnitude 6.3 shock known as the Christchurch earthquake that occurred nearly six months later on 22 February 2011. Because this aftershock was centred very close to Christchurch, it was much more destructive and resulted in the deaths of 185 people.
The main shock on 4 September caused widespread damage and several power outages, particularly in the city of Christchurch, New Zealand's second largest city. Two residents were seriously injured, one by a collapsing chimney and a second by flying glass. One person died of a heart attack suffered during the quake, although this could not be directly linked to the earthquake. Mass fatalities were avoided partly due to there being few houses of unreinforced construction, although this was also aided by the quake occurring during the early hours of the morning when most people were off the street.
The earthquake's epicentre was 40 kilometres (25 mi) west of Christchurch, near the town of Darfield. The hypocentre was at a shallow depth of 10 km. A foreshock of roughly magnitude 5.8 hit five seconds before the main quake, and strong aftershocks were reported, up to magnitude 6.3. The initial quake lasted about 40 seconds, and was felt widely across the South Island, and in the North Island as far north as New Plymouth. As the epicentre was on land away from the coast, no tsunami occurred.
The National Crisis Management Centre in the basement of the Beehive in Wellington was activated, and Civil Defence declared a state of emergency for Christchurch, the Selwyn District, and the Waimakariri District, while Selwyn District, Waimakariri and Timaru activated their emergency operation centres. Initially, a curfew was established for parts of Christchurch Central City from 7:00 pm to 7:00 am in response to the earthquake. The New Zealand Army was deployed to the worst affected areas in Canterbury.