Seddon is a small town in Marlborough, New Zealand. It is located 25 kilometres (16 mi) south of Blenheim, close to the mouths of the Awatere and Blind Rivers and the Lake Grassmere salt works.
GNS Science, officially registered as the Institute of Geological and Nuclear Sciences Limited, is a New Zealand Crown Research Institute. It focuses on geology, geophysics, and nuclear science.
An earthquake warning system or earthquake alarm system is a system of accelerometers, seismometers, communication, computers, and alarms that is devised for rapidly notifying adjoining regions of a substantial earthquake once one begins. This is not the same as earthquake prediction, which is currently not capable of producing decisive event warnings.
Natural Hazards Commission – Toka Tū Ake, also known as the Earthquake Commission Toka Tū Ake, is a New Zealand Crown entity that invests in natural disaster research and education as well as providing natural disaster insurance to residential property owners. The Natural Hazards Insurance Act 2023, which came into effect on 1 July 2024, made a number of changes, including changing the name of the Earthquake Commission to Natural Hazards Commission.
The 1855 Wairarapa earthquake occurred on 23 January at about 9.17 p.m., affecting much of the Cook Strait area of New Zealand, including Marlborough in the South Island and Wellington and the Wairarapa in the North Island. In Wellington, close to the epicentre, shaking lasted for at least 50 seconds. The moment magnitude of the earthquake has been estimated as 8.2, the most powerful recorded in New Zealand since systematic European colonisation began in 1840. This earthquake was associated with the largest directly observed movement on a strike-slip fault, maximum 18 metres (59 ft). This was later revised upward to about 20 m (66 ft) slip, with a local peak of 8 m (26 ft) vertical displacement on lidar studies. It has been suggested that the surface rupture formed by this event helped influence Charles Lyell to link earthquakes with rapid movement on faults.
The 1843 Whanganui earthquake occurred on 8 July at 16:45 local time with an estimated magnitude of 7.5 on the scale. The maximum perceived intensity was IX (Violent) on the Mercalli intensity scale, and possibly reaching X (Extreme). The epicentre is estimated to have been within a zone extending 50 km northeast from Whanganui towards Taihape. GNS Science has this earthquake catalogued and places the epicentre 35 km east of Taihape, near the border of Hawke's Bay. This was the first earthquake in New Zealand over magnitude 7 for which written records exist, and the first for which deaths were recorded.
The 2009 Dusky Sound earthquake was a 7.8 earthquake that struck a remote region of Fiordland, New Zealand, on 15 July at 21:22 local time. It had an initially–reported depth of 12 km (7.5 mi), and an epicentre near Dusky Sound in Fiordland National Park, which is 160 km (99 mi) north-west of Invercargill. It was the country's largest earthquake magnitude since the 1931 Hawke's Bay earthquake, but caused only minor damage and there were no casualties. A tsunami accompanied the event and had a maximum measured run-up of 230 cm (91 in).
The 2010 Canterbury earthquake struck the South Island of New Zealand with a moment magnitude of 7.1 at 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 1869 Christchurch earthquake occurred at 8:00 am on 5 June, near New Brighton, with an estimated Richter magnitude of 6.0. The shock had a Mercalli Intensity of VII–VIII.
The 2013 Seddon earthquake measured 6.5 on the scale and was centred in New Zealand's Cook Strait, around 20 kilometres (12 mi) east of the town of Seddon in Marlborough. The earthquake struck at 5:09 pm on Sunday 21 July 2013 at a depth of 13 kilometres (8 mi), according to GeoNet. The United States Geological Survey also measured the quake at 6.5, at a depth of 17 kilometres (11 mi). The quake caused moderate damage in the wider Marlborough area and Wellington, the nation's capital city 55 kilometres (34 mi) north of the epicentre. Only minor injuries were reported. Several aftershocks occurred during 21–29 July.
The 2013 Lake Grassmere earthquake was a magnitude 6.6 earthquake that occurred at 2:31:05 pm (NZST) on Friday 16 August 2013. The epicentre was located about 10 km south-east of Seddon, under Lake Grassmere, with a focal depth of 8 km. The earthquake caused significant land damage in the local area, with landslips blocking roads, including the main highway between Blenheim and Christchurch. Buildings in Seddon were damaged, with some being declared uninhabitable. The earthquake was widely felt in both the North and South Islands of New Zealand.
The 2014 Eketāhuna earthquake struck at 3:52 pm on 20 January, centred 15 km east of Eketāhuna in the south-east of New Zealand's North Island. It had a maximum perceived intensity of VII on the Mercalli intensity scale. The magnitude 6.2 earthquake was followed by a total of 1,112 recorded aftershocks, ranging between magnitudes 2.0 and 4.9.
The Hikurangi Margin is New Zealand's largest subduction zone and fault.
The 2016 Kaikōura earthquake was a 7.8 earthquake in the South Island of New Zealand that occurred two minutes after midnight on 14 November 2016 NZDT. Ruptures occurred on multiple faults and the earthquake has been described as the "most complex earthquake ever studied". It has been subsequently modelled as having a megathrust component set off by an adjacent rupture on the Humps Fault. It was the second largest earthquake in New Zealand since European settlement.
The 2003 Fiordland earthquake struck the remote region of Fiordland in the South Island of New Zealand on 22 August 2003, at 12:12 am NZST. The epicentre was 12 kilometres (7.5 mi) deep, and was thought to be near Secretary Island at the entrance to Doubtful Sound. At 7.2 Ms magnitude, it was one of the largest quakes in the country for some time, and was the largest shallow quake since the 1968 Inangahua earthquake. There was an aftershock two hours later at 2:12 am, followed over several days by frequent small tremors; two months after the earthquake, there had been 8,000 aftershocks.
The 2021 Kermadec Islands earthquakes were a series of earthquakes with magnitudes of 8.1 and 7.4 that occurred at 19:28:31 UTC on 4 March 2021. The epicentres were located southeast of Raoul Island in the Kermadec Islands, part of the New Zealand outlying islands. The main magnitude 8.1 earthquake was preceded by a magnitude 7.4 foreshock and followed by a magnitude 6.1 aftershock. A separate, unrelated magnitude 7.3 earthquake occurred off the coast of the North Island of New Zealand, approximately 900 km to the south, several hours before the main quakes. More than a dozen aftershocks exceeded magnitude 6.
The Kaikōura Canyon is a geologically active submarine canyon located southwest of the Kaikōura Peninsula off the northeastern coast of the South Island of New Zealand. It is 60 kilometres (37 mi) long, and is generally U-shaped. The canyon descends into deep water and merges into an ocean channel system that can be traced for hundreds of kilometres across the deep ocean floor. At the head of the Kaikōura Canyon, the depth of water is around 30 metres (98 ft), but it drops rapidly to 600 metres (2,000 ft) and continues down to around 2,000 metres (6,600 ft) deep where it meets the Hikurangi Channel. Sperm whales can be seen close to the coast south of Goose Bay, because the deep water of the Kaikōura Canyon is only one kilometre (0.62 mi) off the shoreline in this area.
In 1914, two earthquakes shook the upper North Island of New Zealand, on Wednesday 7 October and Wednesday 28 October. They were large and shallow, with their epicentres close together northwest of Ruatoria in the Gisborne District. The earthquakes were felt strongly throughout the East Cape area, most noticeably in areas east of the epicentre such as Waipiro Bay, with a large amount of damage occurring in Tokomaru Bay in particular. One person was killed by a landslide near Cape Runaway.
