![]() Within roughly 24 hours, AIR issued estimates of industry losses and was assisting clients assess losses to their own portfolios. On September 4, 2010, the day after the Christchurch earthquake, AIR earthquake researchers were running simulations of the event using the available information on epicentral location, depth, magnitude and direction of rupture. Scientists are still trying to determine the exact location and extent of the newly discovered fault. ![]() They believe that when it ruptured it activated the Greendale fault. GNS scientists identified a previously unknown, blind thrust fault nearby and to the north, which also ruptured on September 4. Indeed scientists believe that the most recent rupture of this fault occurred before the last glaciations-about 18,000 years ago.įurther findings in the weeks following the earthquake suggested that the Greendale fault was not the only actor. According to officials at New Zealand’s Institute of Geological and Nuclear Sciences (GNS), prior to the event on September 4, nothing in the plains landscape would have suggested a fault lay below.Īfter the quake struck, scientists hypothesized that the Greendale fault was the culprit, although the fault had not been considered active because there were no observable earthquake-related geomorphic features on the surface to identify it. ![]() It produced a 22 kilometer-long surface rupture in the Canterbury Plains near the town of Darfield, 35 kilometers west of Christchurch. The Christchurch earthquake was the most damaging seismic event in New Zealand since the Hawke's Bay quake in 1931. Only around 20 of these have a magnitude in excess of 5.0, on average, and roughly 10 cause discernable damage. Many Events, Little Damage: New Zealand’s Tectonic Settingīeneath New Zealand, the Australia and Pacific plates collide, resulting in high seismicity more than 14,000 earthquakes occur along this section of plate boundary each year. Not surprisingly, the legislation has resulted in some controversy, such as whether the government may be too quick to demolish historic heritage buildings and whether homeowners will be prevented from rebuilding in areas where damage from liquefaction was severe. Its goal is to ensure the government has adequate power to facilitate a prompt response, giving parliament the power to proceed with the task of rebuilding damaged homes, business premises and infrastructure. Officials cordoned off streets in order to individually assess buildings.īy mid-September, the government had passed the Canterbury Earthquake Response and Recovery Act. Immediately following the earthquake, officials in Christchurch activated the building safety evaluation process developed by the New Zealand Society for Earthquake Engineering. ![]() Nonstructural damage-such as to parapets and chimneys-was more common according to early estimates, over 15,000 chimneys sustained damage considered severe 1. Those buildings most severely impacted were unreinforced masonry (URM) structures, particularly older URM structures, of which there are a number in Christchurch, the South Island’s oldest city. A week later, AIR was collaborating with researchers on the ground in Christchurch to perform a damage survey. Within roughly 24 hours of the event, AIR issued insured loss estimates to residential and commercial buildings between NZD 2,700 million (2.0 billion USD) and NZD 6,000 million (4.5 billion USD). The quake, which struck 45 kilometers west of downtown Christchurch, in the Canterbury Plains of New Zealand’s South Island, was a strong magnitude event with a shallow focal depth (5 kilometers). Just after 4:30 AM local time (16:35 UTC) on September 4, 2010, thousands of New Zealanders were jostled awake by an earthquake registering 7.0 on the moment magnitude scale. ![]()
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