Early days
Māori have many accounts of violent earthquakes in the early days of settlement, including one at Rotorua where it was said that a pā (fortified village) was swallowed up and the land became a lake.
European settlement
From 1840, European settlers began arriving. Over the next century, there were several major earthquakes, including:
- Wairarapa, 1855 (magnitude 8.2). New Zealand’s most powerful recorded earthquake lasted nearly a minute. Wellington was worst affected, but many wooden buildings survived. Up to nine people died.
- Murchison, 1929 (7.8). Felt throughout the country, this quake caused damage in Nelson, Westport and Greymouth. Murchison was devastated by landslides which killed 14 people.
Hawke’s Bay, 1931
This magnitude 7.8 earthquake struck at 10.48 a.m. on 3 February 1931. It was New Zealand’s deadliest, crippling Napier and Hastings. In Napier, ornate stone buildings collapsed and people rushed outside, only to be hit by falling masonry and roofs. Others were trapped in rubble. Water pipes burst and fires soon raged, gutting the central district. 256 people died.
Aftershocks continued for months and many people moved to refugee camps. But within two years the city was rebuilt with safer buildings – many in the 1930s art deco style.
1942 onwards
These major quakes have struck New Zealand since 1931:
- Wairarapa, 1942 (7.2 and 6.8). These two earthquakes caused damage in Masterton, Wellington, and other centres. In Wellington alone, 10,000 chimneys were damaged.
- Inangahua, 1968 (7.1). This rocked the northern South Island, throwing people out of bed. Roads were blocked and 50 bridges collapsed.
- Edgecumbe, 1987 (6.3). Although smaller, this quake caused major industrial damage. Dozens were injured and a huge crack appeared in the Rangitāiki Plains.
- Canterbury, 2010 (7.1) and 2011 (6.3). While the 2010 earthquake was larger, the 2011 earthquake was more devastating in Christchurch city. Most of the 185 people who died in the 2011 quake were killed in collapsed buildings.
- Kaikōura, 2016 (7.8). This quake caused significant damage to buildings and infrastructure in southern Marlborough and northern Canterbury. Two people died.
The 1848 Marlborough earthquake
European settlers arriving in the Wellington region from 1840 onward soon became accustomed to a distinctive feature of the new land: the numerous small earthquakes. Because these minor tremors caused no damage, people were ill-prepared for the severity of the quakes that were to follow.
Intensity of the earthquake
On 16 October 1848 an earthquake with an estimated magnitude of 7.5 shook the region. Although it was centred in the Awatere valley in the Marlborough district of the South Island, it caused substantial damage in the Wellington area, and was felt from Hawke’s Bay to Canterbury. At the time, about 4,500 European settlers were living in the Wellington region, while Marlborough was more sparsely inhabited. Māori settlements were scattered along the coast.
The first earthquake occurred at 1.40 a.m. during a severe gale and heavy rain. The main shock lasted for at least two minutes, and was followed by strong vibrations for 10 minutes. Vibrations continued for at least an hour, increasing to earthquake shocks every few minutes. Judge Henry Chapman noted about 100 aftershocks between 1.40 a.m. and 6 a.m.
Impact in Wellington
In Wellington the violent shaking damaged almost all brick and stone buildings, including many homes, commercial buildings, churches, barracks, the jail, and the colonial hospital. Wooden buildings survived, but many lost their brick chimneys. In Marlborough, a number of homesteads were badly damaged.
Major aftershocks on 17 and 19 October brought down a number of buildings that had been damaged in the first earthquake. Many people in Wellington described these aftershocks as being as strong as or stronger than the initial earthquake.
Rumblings in the press
Lieutenant-Governor Edward Eyre described the effects of the 1848 earthquake in alarming terms: ‘the town of Wellington is in ruins … Terror and dismay reign everywhere … ships now in port … are crowded to excess with colonists abandoning the country’. 1 Angry newspaper editorials blasted Eyre’s catalogue of desolation and gloom, fearing that his descriptions would deter new immigrants and discourage business investment.
After the quake
As aftershocks continued, some people sought safety at night aboard ships in the harbour. Others decided to leave permanently: on 26 October the barque Subraon set sail for Sydney with over 60 settlers. It struck rocks near the Wellington Harbour entrance and was wrecked, but no lives were lost. Many of the rescued settlers eventually stayed in Wellington.
On the other hand, those living near the earthquake epicentre thought Wellington would be a refuge. After the first few days of frightening tremors, whalers from Cloudy Bay, Marlborough, took their families to Wellington in an open boat, despite stormy weather.
Surprisingly, only three people died in the 1848 tremors. A barrack sergeant and his son and daughter were fatally injured on 17 October, when the brick wall of a damaged building collapsed during a major aftershock.
Soon after the earthquakes, the settlers were clearing ruins and rebuilding. Mindful of the severe damage to brick and masonry buildings, many chose to replace them with wooden buildings.
The cause
The 1848 earthquakes, and the aftershocks which continued well into 1849, were caused by movement along at least 105 kilometres of a major fault along the Awatere Valley. Along the fault, land moved as much as 8 metres horizontally. Matthew Richmond, the resident magistrate of Nelson, visited the area in November 1848. An account of his visit noted that ‘a crack quite straight crossed the country for miles; in some places he had difficulty crossing it with his horse; in one place the crack passed through an old warre [whare] dividing it in two pieces standing four feet apart.’
The 1855 Wairarapa earthquake
In 1855 a magnitude 8.2 earthquake – the most powerful ever recorded in New Zealand – rocked the southern part of the North Island. Caused by movement along a fault in Palliser Bay, it altered the landscape of the Wellington region and affected its subsequent urban development.
Intensity of the earthquake
The evening of 23 January 1855 was the end of a two-day holiday, the 15th anniversary of Wellington’s founding. Shortly after 9 p.m. a violent earthquake began; in Wellington the main shock lasted for at least 50 seconds. People fled outdoors, where they remained for the night in tents and makeshift beds, as incessant aftershocks rocked the area – one person counted 250 in the first 11 hours. The aftershocks would continue for months. For the first day after the main quake, as far away as New Plymouth an almost continuous vibration could be felt by people sitting, or when leaning against walls.
Rebuilding
After the 1848 Marlborough earthquake, many Wellington buildings had been rebuilt in wood. Some new commercial premises, however, were constructed of brick because of fire risk. The 1855 earthquake damaged many of these, including the jail and the bank. The local council chambers and adjoining government offices, both two-storey wooden buildings, collapsed. However, single-storey wooden houses survived: although many were damaged by falling brick chimneys, or shifted on their foundations, few collapsed.
Fatalities
The number of fatalities caused by the earthquake is estimated at between five and nine. The sole casualty in Wellington was Baron von Alzdorf, who died when a brick chimney in his hotel collapsed. Two people died in a fissure in Manawatū. In Wairarapa, several Māori (the reported number varies from two to six) were killed when a whare collapsed. Surprisingly few people were injured.
Effects on land and sea
In Hutt Valley, slips blocked roads and large fissures opened up in the ground. Numerous landslides scarred the slopes of the Remutaka Range. The earthquake caused a tsunami in Cook Strait and Wellington Harbour; some buildings on Lambton Quay near the shoreline were flooded by tsunami waves.
The day of the tsunami
The tsunami caused by the 1855 earthquake had several sources. Water first spilled onto the land because the land west of the Wairarapa Fault shifted abruptly north-east. Next, because Wellington’s harbour was raised more on the eastern than on the western side, the harbour waters moved toward the lower side, flooding Lambton Quay.
A tsunami with waves up to 10 metres high was generated in Cook Strait, probably by submarine uplift. These waves entered Wellington Harbour and washed back and forth. The commander of the Pandora, anchored in the harbour, reported: ‘for eight hours … the tide approached and receded from the shore every 20 minutes, rising from eight to ten feet and receding four feet lower than at spring tide.’ 1
The cause
The earthquake was caused by movement along at least 140 kilometres of the Wairarapa Fault, along the eastern edge of the Remutaka Range. About 5,000 square kilometres of land west of the fault was lifted up and tilted. The southern end of the Remutaka Range rose by over 6 metres, but the uplift decreased westward to near zero along the west coast of the Wellington peninsula. Across Cook Strait, the seaward end of the Wairau valley subsided over a metre. Land also shifted over 18 metres horizontally along the Wairarapa Fault.
Changes to the landscape
The uplift created a new fringe of beach and rock platforms along the Wellington coast. Many jetties in Wellington Harbour became unusable, but there were also beneficial effects. Blocks of the city’s central business district now occupy land that was below sea level before 1855. The newly exposed strip of shoreline between Wellington and Hutt Valley offered a safe road and railway route – parts of the coastal road had previously been impassable at high tide. The uplift of the region helped drain the swampy lower reaches of Hutt Valley. Commerce lost but sports gained when a low-lying area known as the Basin Reserve, originally proposed as a shipping basin, instead became Wellington’s cricket ground.
Aftermath
While memories of the 1848 and 1855 earthquakes were fresh, most of the new buildings in Wellington were constructed of wood. The old Government Buildings, opened in 1876, is one of the most impressive wooden structures of this period, with a facade imitating a classical European stone building.
However, it took only 25–30 years for awareness of building safety to fade. Masonry construction gradually returned, encouraged by city council regulations for fire resistance. By the beginning of the 20th century the earthquake hazard was largely discounted, and between 1913 and 1926 the New Zealand Official Yearbook included the comment that ‘earthquakes in New Zealand are rather a matter of scientific interest than a subject for alarm’.
The 1888 North Canterbury earthquake
In the early morning of 1 September 1888, an earthquake with an estimated magnitude of 7.0–7.3 struck the Amuri district of North Canterbury, about 100 kilometres north-west of Christchurch. Felt from New Plymouth to Invercargill, the quake caused damage to buildings over a wide area, including Christchurch.
Although many major earthquakes have struck without warning, this one was heralded by three weeks of noisy foreshocks, which people in Amuri heard as distant rumblings. On 30 August tremors were felt in the Hope Valley from 6.20 p.m. onward, gaining in intensity until an earthquake at 10 p.m. stopped clocks and rang church bells in Canterbury and Westland. More tremors followed the next day. In the late evening they increased in strength and frequency, growing louder until they became deafening before the main earthquake struck at 4.10 a.m. on 1 September.
The heavy shaking lasted 40 to 50 seconds in Christchurch, and there were many aftershocks, several of them felt in Christchurch in the first quarter-hour after the main quake. Aftershocks continued beneath the Hanmer Plains for more than a month.
Damage
In North Canterbury, especially in the Hope valley and Hanmer areas, many farm buildings were badly damaged or destroyed, including cob structures (made of rammed earth) and brick and stone buildings. Wooden buildings shifted off their foundations or were badly warped. The earthquake caused landslides in loose sediment, and fissures up to 30 centimetres wide appeared along terraces of the Percival River and in the Hanmer Plains.
In Christchurch, the most notable damage was to Christchurch Cathedral. The top 7.8 metres of the stone spire collapsed, in part because of the sway of the heavy iron cross secured to its top. The Durham Street Wesleyan Church lost some stonework, and the Normal School in Cranmer Square had cracked ceilings and damaged chimneys. Many homes also had broken chimneys and windows. There was more damage in the northern and north-western suburbs, probably due to the peaty subsoils underlying the buildings there. At Lyttelton, boats swung at their moorings, and 10-ton blocks of rock tumbled from bluffs along the Sumner road.
Lamenting a landmark
This report appeared in the Lyttelton Times on 5 September 1888:
‘[T]he spire of the Cathedral has come to grief. Its tapering, graceful outline, a landmark for every dweller on the plains within thirty miles, and a beacon for the mariner crossing Pegasus Bay, no longer cuts the sky. Twenty-six feet of the upper spire have given way, and the melancholy appearance of the wreck strikes every eye.’
Strong shaking was reported from the Ōtira Gorge, where new hot springs were observed. Households in Hokitika and Greymouth had damaged chimneys and broken crockery.
The cause
The earthquakes were caused by movement along a 30-kilometre section of the Hope Fault, from the junction of the Hope and Boyle valleys to the Hanmer Plain. This major fault crosses the South Island from the Alpine Fault at the Taramakau River to the coast north of Kaikōura. In the Hope valley west of the Hanmer basin, geologist Alexander McKay discovered that farm fences had been offset horizontally by 1.5 to 2.6 metres along the fault. He was the first in the world to show that horizontal movement could occur along faults during earthquakes.
The 1929 Arthur’s Pass and Murchison earthquakes
Arthur’s Pass earthquake
At 10.50 p.m. on 9 March 1929 a magnitude 7.1 earthquake shook the mountain region near Arthur’s Pass for four minutes. Nearly continuous tremors followed for an hour, and aftershocks continued for days. Chimneys and water tanks collapsed, and rocks thundered down the nearby mountain slopes. Railway lines were damaged and slips closed the highway to the West Coast for several months. Despite the damage to houses, no one was injured. Two years later trampers discovered that a mountainside had collapsed during the earthquake, creating a huge landslide that swept 5 kilometres down the Otehake River. The earthquake is believed to have been caused by up to 4 metres of land movement along the Poulter Fault.
Shake, rattle and roll
Saturday night, 9 March 1929, found many people at a dance at the social hall in Arthur’s Pass. J. L. Spiers, a railway porter, commented: ‘The first indication of the shock was the middle of the roof descending about 18 inches, and the walls bulging out. Then the walls came in again and the floor went up and down.’ The lights went out, but there was no panic. When matches were struck, some of the people were found lying on the floor. 1
Murchison earthquake
On 17 June 1929, at 10.17 a.m., a magnitude 7.8 earthquake struck the northern South Island. It was felt in cities and towns all over New Zealand. Nelson, Westport and Greymouth reported damage, but it was half a day before authorities realised that the worst hit region was Murchison.
For days preceding the earthquake, booming noises had been heard in the hills around Murchison. The earthquake itself was exceptionally noisy: rumblings were heard in New Plymouth, over 250 kilometres away. It was caused by movement along the White Creek Fault west of Murchison. Land moved upward as much as 4.5 metres along the fault.
When the main shock struck, wooden homes warped, twisted and shifted from their piles, and chimneys and water tanks collapsed. People scrambled outdoors, but once there found they were unable to stand.
A slip at school
Bob White, a pupil at Whale’s Flat school during the 1929 Murchison earthquake recalled:
‘We managed to get out near the gate and were thrown to the ground, which was rocking and heaving like a boat on huge waves by this time. After I suppose a minute … I saw a huge slip hurtling towards us. I yelled and we got to our feet and endeavoured to run back toward the building but the slip overtook us and went straight through the school, leaving the roof perched on top. We were saved by some poplars and a chestnut tree.’ 2
Landslides
The shaking triggered dozens of huge slips on the steep mountain slopes, which were waterlogged from winter rain. Landslides blocked many rivers, including the Matiri, Maruia, Mōkihinui and Buller. The landslide dam on the Mōkihinui River later burst; the resulting flood seriously damaged Seddonville.
A massive landslide swept over the Busch and Morel homes, killing four people and damming the Mātakitaki River. In the Maruia valley a landslide pushed the Gibson home across a road and into a gorge, killing three people. Another swept the Holman home into the river, killing two. Of the 17 people who died in the earthquake, 14 were killed by landslides, and 2 in coal mine collapses.
The aftermath
With their homes uninhabitable and aftershocks continuing, residents camped in the open, or in sheds and tents. Communal kitchens were set up, but food supplies ran low. The landslide-dammed rivers posed a danger of flooding, so over several days most people left Murchison. They travelled part of the way in cars, then continued on foot, negotiating slips and streams. They eventually reached Glenhope, where they caught trains to Nelson.
Nelson, Greymouth and Westport had many damaged chimneys and brick buildings – the tower of Nelson Boys’ College collapsed, injuring two boys. In Karamea, damage was minor but numerous slips blocked the coastal road and food ran short. No outside help arrived until an aviator landed a Tiger Moth plane on the beach two weeks later. Vehicles could not reach the town for several months.
Core research
In 1936 the Danish seismologist Inge Lehmann used records taken from around the world of the Murchison earthquake to demonstrate that the earth has a solid inner core. It was an important breakthrough in understanding the nature of the earth’s interior.
In an era when road work was carried out with pick and shovel, many roads buried by slips in the Buller region did not re-open for months. The Westport to Reefton road was closed for 18 months.
The 1931 Hawke’s Bay earthquake
In 1931, New Zealand’s deadliest earthquake devastated the cities of Napier and Hastings. 256 people died in the magnitude 7.8 earthquake – 161 in Napier, 93 in Hastings, and 2 in Wairoa. Many thousands more required medical treatment.
256 or 258?
The official death toll of the Hawke’s Bay earthquake is 256, but there are 258 names on the memorial. In 2019, academic researchers identified 17 new victims – and established that 17 people previously identified as victims actually weren’t.
On Tuesday morning, 3 February 1931, at 10.47 a.m., the ground in the Hawke’s Bay region heaved sharply upward and swayed. A deceptive half-minute pause was followed by a downward motion and violent shaking and rocking. In all, the quake spanned two and a half minutes.
Fatalities
As buildings began to disintegrate, many people fled outdoors into a lethal rain of chunks from ornate facades, parapets and cornices. Buildings swayed violently, and their walls bulged and collapsed into the streets in avalanches of brick and masonry that crushed vehicles and people. Roofs caved in on buildings that had large open internal areas, such as churches, libraries and theatres. In some buildings the internal floors pulled free of the swaying walls, collapsing inward in a jumble of girders, wood and plaster.
In Napier, the recently built Nurses’ Home collapsed, killing clerical staff and off-duty nurses who were sleeping. In Hastings at least 50 people were in Roach’s department store when it collapsed; 17 died and many were seriously injured. The entire front of the five-storey Grand Hotel in Hastings crumbled into Heretaunga Street, claiming eight lives. Fifteen died at the Park Island Old Men’s Home near Taradale, but a 91-year-old man was pulled alive from the rubble three days later.
The earthquake struck on the first day of school after the summer holidays. Most pupils managed to escape to the outdoors in time, but nine students died in the wreckage of the brick Napier Technical College. Several of those students had gone back into the school to rescue trapped classmates. Seven students also died at the Marist Fathers’ Seminary in Greenmeadows.
Everybody out
This account is from Jock Stevens, who was at Napier Boys’ High School when the earthquake struck:
‘[A] boy said “Earthquake, Sir!” We were immediately struck with the full force of the quake. The master in charge, Matt Alexander, said “Everybody out!” … The shakes sent me flying onto the floor of the doorway and I can still feel the feet of the class trampling over me. I got to my feet and from there I saw the Assembly Hall collapse like a pack of cards – each wall fell in then the tiled roof came down. Then dust clouds blotted it out.’ 1
The fires begin
Within minutes of the earthquake, fire began in three Napier chemist shops in the business district. Firefighters were almost helpless – water pressure faded to a trickle as the reservoir emptied. Attempts to pump sea water from the beach were short-lived, as hoses quickly became blocked by shingle. By mid-afternoon Napier’s business area was ablaze. Some 36 hours later, after a remarkable attempt by firemen, volunteers and sailors working through the night, the fires were extinguished. Almost 11 blocks of central Napier were gutted. Fires also sprang up in Hastings, but water supplies were available there shortly after the earthquake and fire damage was less extensive.
Ahead of the spreading fires and amidst continuing aftershocks, desperate rescuers, using crowbars, shovels, picks, and their hands, worked to reach people trapped in wrecked buildings. Some could not be rescued in time; a doctor administered a lethal overdose of morphine to an injured woman trapped in the ruins of St John’s Cathedral before fire reached her. A number of rescuers were killed as aftershocks caused further collapses.
Rescue work
The navy sloop HMS Veronica had berthed in Napier’s harbour that morning. When the earthquake struck, the harbour bottom rose, leaving the ship aground. On deck, sailors watched as the wharf buckled, roads split open, and buildings collapsed in clouds of dust. The Veronica radioed Auckland, and within hours the cruisers HMS Dunedin and Diomede were on their way, each carrying 450 men and officers, doctors and nurses from Auckland Hospital, and medical and emergency equipment. They arrived the following dawn. Meanwhile, teams of the Veronica’s sailors spread out into the town to help with rescue efforts.
Napier’s hospitals were badly damaged and unusable, so patients were moved to the lawns of the Botanical Gardens, where a surgical station was set up. Emergency hospitals were set up at the Hastings racecourse and at Napier Park racecourse, where doctors operated beneath the grandstand. In the ensuing days, many injured people were evacuated to other centres.
Aftershocks
After the earthquake most homes lacked water, electricity, sewerage and chimneys, and people camped in open areas as continuous tremors made it dangerous to stay inside. Within a day the army had set up a tent camp that could house 2,500 people. Women and children were encouraged to leave the area, and refugee camps sprang up in a number of North Island towns. Able-bodied men were required to stay to provide labour for search, demolition and clean-up.
Ten days after the quake, the region was shaken by the largest aftershock since the initial earthquake, a powerful magnitude 7.3 jolt that did yet more damage to already weakened buildings.
In the Napier earthquake
‘Then the world collapsed, or exploded. I knew not what was happening as I had never experienced an earthquake. Where grandad had been resting a minute before, a huge wardrobe crashed down. The noise of chimney bricks smashing onto the roof was alarming.’ Donald Locke remembers the Napier earthquake of 1931.
For people who lived through the Napier earthquake of 3 February 1931, the moment the big shake arrived became indelibly sketched on the memory. But for most people the quake was only the beginning. There followed days of looking after the injured, dealing with rubble and sometimes fire, and long nights of personal anxiety. Aftershocks continued for weeks.
Rebuilding Napier
On 11 March 1931 the government appointed magistrate J. S. Barton and engineer L. B. Campbell as commissioners for Napier. Together with local committees they had the daunting task of organising reconstruction. This included restoring water supplies, replacing sewers, and repairing and inspecting houses before they could be reoccupied. Local survey plans and land titles had been destroyed, so all properties were resurveyed, and interim titles were issued.
Few insurance policies covered earthquakes, and many insurers refused to pay for fire damage that resulted from the quake. In 1931 Parliament had passed the Hawke’s Bay Earthquake Act, which provided loans for local companies and individuals to rebuild their premises. Because of the economic depression, however, the funds granted were far from adequate, and repayment terms were harsh. Much of the money for recovery came from charity, which poured in during the weeks after the quake.
A safer city
Napier was presented with a unique opportunity: the wholesale replacement of its city centre. The city authorities did not want haphazard growth, so a temporary shopping centre, dubbed Tin Town, was built at Clive Square. It was used for several years while the city centre was being rebuilt. Napier’s new town centre boasted many improvements, including wider streets and some of New Zealand’s earliest underground power and telephone lines.
The loss of life caused by the collapse of so many buildings shocked the country. Engineers studied the building damage to identify the most dangerous defects in design and construction. A Buildings Regulations Committee developed guidelines to ensure the new buildings were safer; their recommendations were the forerunner of building codes now used throughout New Zealand.
Architectural influences
Four rival architectural practices joined to share resources and ideas. The buildings of Louis Hay reflected the designs of American architect Frank Lloyd Wright. Natusch & Sons’ buildings were simple in style, often using arched windows, and Finch & Westerholm produced many Spanish mission style buildings. Most popular was the art deco style of the time, which emphasised spare, clean lines and geometric motifs. E. A. Williams designed some of Napier’s most striking art deco buildings. Their austere modernistic design contrasted sharply with the ornate edifices that had caused so many deaths. Many of these 1930s buildings have since been restored, and are now major attractions.
In November 1932, Hastings celebrated its reconstruction, and in January 1933, almost two years after the earthquake, during the New Napier Carnival, Napier was declared officially ‘reborn’.
An altered landscape
Shortly after the earthquake, hundreds of people had made their way to the beach, seeking a safe haven from crumbling buildings. There they found that the sea had retreated far from the shoreline, and many feared a tsunami.
The sea had gone out – for good. The Napier earthquake had been caused by movement along a fault buried deep beneath the region. When it moved, an area above the fault, about 90 kilometres long and 15 kilometres wide, domed upward. The land and sea floor were raised by as much as 2.7 metres.
Napier had extensive areas of wetlands, including Ahuriri Lagoon, popular for fishing and recreation. As the land rose, sea water drained from the lagoon, gifting Napier with more than 2,000 hectares of new land. Drains were later put in and eventually rain flushed the sea salt from the soil. The former lagoon became productive land, and the site of Hawke’s Bay airport. Along Napier’s Marine Parade debris from landslides and demolished buildings was placed on the newly upraised foreshore and covered with soil to create a broad garden esplanade.
The 1942 Wairarapa earthquakes
During the Second World War, in 1942, two powerful earthquakes on 24 June and 2 August caused substantial damage to many towns in the Wairarapa, and in Wellington. The epicentres of the earthquakes were both near Masterton, but because the August main shock was much deeper than the June earthquake, it was less severe. They were caused by movement along buried faults, so the fault ruptures did not reach the surface.
The first earthquake
On 24 June there was a minor earthquake at 8.14 p.m., followed at 11.16 p.m. by a magnitude 7.2 earthquake that was felt from Auckland to Dunedin. This main shock lasted about a minute, and aftershocks continued through the night: over 200 were felt before 7 a.m.
The earthquake was centred near Masterton, and the heaviest damage was in the town’s business area. Many shops had brick facades with ornate parapets and gable ends. These crashed into the street, taking with them the wooden verandahs that sheltered the footpaths and the electricity and telephone lines. Heavy roofs and water tanks collapsed. In many Wairarapa towns, including Eketāhuna, Martinborough, Gladstone, Carterton and Greytown, churches and commercial premises, especially brick buildings, were damaged. Most houses in the Wairarapa were timber framed – they survived the shaking well, but almost all lost their brick chimneys. Close to the epicentre, however, some houses shifted off their foundations.
Rocking the baby
‘I was just going to bed when we got this terrific shake. We could hear bricks coming down through the roof into the room where our baby was sleeping. I crawled along the passage – you couldn’t walk, the whole place was rocking so badly. It was terrifying. I could hear the baby screaming but I couldn’t get to the cot because of the rubble in the room. The cot shot from one side of the room to the other with the violence of the quakes. I finally found the cot, got the baby out and we sat underneath.’ 1
Effects in Wellington
In Wellington, 80 kilometres from the earthquake epicentre, buildings swayed and people rushed into the streets. Walls in many older buildings cracked, windows shattered, and in the central city, bricks, concrete and masonry came crashing down onto footpaths. In the countryside, the earthquake caused many landslides, and damaged roads, railway lines and bridges.
Only one person died – a man in Wellington was killed by coal gas escaping from a fractured pipe. Had the earthquake struck during shopping hours, many might have died; but it hit late on Saturday evening, when movie theatres had closed and few people were about.
The army was called in to assist with demolition and clean-up, and to guard buildings. Bricklayers from all over New Zealand came to help rebuild and repair the thousands of wrecked chimneys.
The second earthquake
About five weeks later, while the damage was still being repaired, earthquakes struck again. A magnitude 5.6 tremor was felt in the late afternoon of 1 August. It was followed by a magnitude 6.8 earthquake at 12.34 a.m. the next day, felt through much of New Zealand.
Damage
Structural damage in Wellington and the Wairarapa was extensive, due to the cumulative effects of the two earthquakes. Eketāhuna suffered more damage than in June. Two blocks of Manners Street in Wellington were closed for several months because of the dangerous state of the buildings. One Wellington building had lost 316 windows in June: 100 shattered in the August earthquake. In Wellington at least 5,000 houses and 10,000 chimneys were damaged by the two major earthquakes. Several years later, many buildings were still unrepaired. This prompted the government to set up an Earthquake and War Damage Commission for earthquake insurance in 1944.
The 1968 Īnangahua earthquake
In the early morning of 24 May 1968, the northern South Island was rocked by a magnitude 7.1 earthquake centred near Īnangahua Junction, a small community 40 kilometres east of Westport. At 5.24 a.m. people there were woken by shaking violent enough to throw them out of bed. Many hastily escaped from their homes, amidst falling chimneys and roof tiles.
At Whitecliffs a limestone bluff collapsed onto a farmhouse and pushed it downhill, killing one woman instantly and fatally injuring another. Shortly after the earthquake, one man died near Greymouth when his car hit a section of road that had subsided at a bridge approach. Three men were killed later when a helicopter crashed.
Effects in Īnangahua
At daylight, a relief centre was set up in the Ministry of Works yards in Īnangahua. People gathering there were dismayed to hear radio news broadcasts at 6.30 a.m. mention only mild earthquakes – the rest of New Zealand seemed unaware of Īnangahua’s plight. All roads out of the area were blocked and there was no telephone, or electricity to send radio messages. Several hours later, however, a driver contacted Gisborne on his truck radio. By late morning commercial and air force helicopters were coming into the area to survey damage.
The earth explodes
Ruth Inwood, an Īnangahua dairy farmer, recalls the moment the quake struck:
‘I thought it was the end of the world … The noise was horrendous. …Our fridge was flipped on its side, a heavy three-seater sofa was thrown across the lounge, ceilings were ripped open, windows exploded out of their frames, cupboards were completely emptied, and broken ornaments and crockery littered the floor. … It was like an explosion underneath us. The house was shunted up in the air and then it shook violently. A lot of houses were knocked clean off their piles.’ 1
The impact elsewhere
Other West Coast towns were heavily shaken: more than two-thirds of the chimneys in Greymouth, Westport and Reefton were damaged. Reefton residents realised that help would be needed in isolated areas. Four people, including a constable and a doctor carrying a pack of medical supplies, walked to Īnangahua Junction. There the doctor treated most patients outdoors because aftershocks were still jolting the area.
Landslides
The Īnangahua tremors triggered numerous landslides in the surrounding mountains. A huge landslide dammed the Buller River above Īnangahua Junction. The rising water backed up for 7 kilometres, raising the river 30 metres above its normal level. If the landslide dam had burst, the river would have flooded not only Īnangahua but also Westport. Everyone in its path had to be evacuated.
Twelve hours after the quake, one group of about 50 people started walking from Īnangahua Junction towards Reefton. Army and commercial helicopters began flying people to Rotokohu, where they could board buses to Reefton, while air force helicopter crews checked all outlying farmhouses. In all, 235 people were airlifted out. The earth-filled river eventually overflowed the landslide debris, but eroded it downward gradually without causing serious flooding.
The earthquake ruined many years of costly work improving and sealing the highways in the Īnangahua and Buller Gorge areas. Over a 50-kilometre stretch, the road through Buller Gorge was blocked in more than 50 places, either buried under slips or with gaps where the road itself had fallen into the gorge. The earthquake had damaged or destroyed 50 bridges. It also derailed two goods trains, and over 100 kilometres of damaged railway track had to be re-laid.
The 1987 Edgecumbe earthquake
At 1.35 p.m. on 2 March 1987, a magnitude 5.2 earthquake struck the Bay of Plenty region, cutting power and sending many people outdoors. Minutes later a much stronger quake rocked the region. This main shock, at 1.42 p.m., had a magnitude of 6.3 and was centred north of Edgecumbe. Four aftershocks with magnitudes greater than 5 occurred in the next six hours, and smaller aftershocks were felt for weeks.
Widespread damage
The Edgecumbe earthquake was the first since the 1968 Īnangahua quake to cause major damage. Although not of an exceptional magnitude, it was damaging because it was very shallow. No one was killed, but several dozen people suffered serious injuries. One woman was hurt by a falling piano in her home, and another was hit by a bull thrown out of its pen at a stock yard.
Industrial sites were badly affected. At the Tasman Pulp and Paper Mill in Kawerau a loaded logging truck toppled onto its side. Mill workers escaped from falling debris through a maze of twisted stairs and walkways. One man was thrown over the rail of a catwalk to the concrete floor 3 metres below. Another was trapped under 11 huge circular saws, each of them 2 metres in diameter. Following the main shock, an engineer checking for structural damage fell 5 metres from a platform.
At Bay Milk Products in Edgecumbe, huge stainless steel milk silos collapsed, spilling thousands of litres of milk. Two milk tankers were thrown on their sides. At the N.Z. Distillery Company, tanks of spirits collapsed, saturating the ground with vodka and gin.
In Kawerau 40 houses were evacuated because of an unstable hill above them. A major worry was the large earthfill hydro dam at Matahina on the Rangitāiki River. Staff found minor cracks in the roadway and concrete abutments. They opened the floodgates to lower the lake level, but controlled the flow to ensure the river would not overtop its stopbanks downstream. Below the dam, the residents of Te Mahoe were evacuated as a precaution. The dam was repaired in 1988, and subsequently strengthened in the late 1990s to withstand earthquake motion.
Some roads cracked or acquired ‘judder bars’ as the ground buckled. Railway tracks were twisted and bent, and a diesel-electric locomotive toppled over.
Tall stories
In the hours after the Edgecumbe earthquake, accounts of the disaster became wildly exaggerated. The tremors produced a massive dust cloud on Moutohorā (Whale Island), an extinct volcano off the coast. Soon there were ‘eyewitness reports’ that the island had erupted. A Singapore newspaper quoted ‘the Police’ as saying that 95% of homes in the Kawerau, Whakatāne and Edgecumbe areas were uninhabitable. In the United States, Washington radio stations reported that 400,000 people had been made homeless. The New Zealand Embassy in Washington was inundated with calls from worried people seeking news.
The Edgecumbe Fault
The most spectacular effect of the Edgecumbe earthquake was the 7-kilometre-long rift that appeared across the Rangitāiki Plains – the Edgecumbe Fault. A fissure up to 3 metres wide and 3–4 metres deep opened up along much of the fault, although some sections were marked just by zones of cracks. A woman who had been picking fruit was thrown from a ladder by the quake. Soon after, she was driving hurriedly down a road to check her home when her car became airborne and flew 6 metres across the rift, landing at the bottom of the scarp.
The earthquake had been caused by movement along the fault; the land to the north-west had dropped by up to 2 metres. The region which sank downward is now more prone to flooding.
The 2010 Canterbury (Darfield) earthquake
A magnitude 7.1 earthquake occurred near Christchurch at 4.35 a.m. on Saturday 4 September 2010. Widely felt over the South Island and the southern North Island, it caused considerable damage in central Canterbury, especially in Christchurch. It was the largest earthquake to affect a major urban area since the 1931 Hawke’s Bay earthquake.
The epicentre was 37 kilometres west of Christchurch, near the town of Darfield. Because of this, its scientific name is the Darfield earthquake, though it is more widely known as the Canterbury earthquake. It was a relatively shallow earthquake – about 10 kilometres below the surface of the Canterbury Plains. During the strong shaking, the ground near the epicentre moved at up to 1.25 times the acceleration due to gravity. The earthquake was accompanied by a large surface rupture.
Internet earthquake
The Darfield earthquake was the first in New Zealand in which social media were used to share information. GeoNet earthquake reports were sent out using both Twitter and Facebook after each major aftershock. Twitter was regularly swamped with messages reporting what people had felt, as well as demands that GeoNet hurry up and post the location and magnitude.
Damage
There were few serious injuries, although one woman, Lillian Daniels-Witika, suffered a fatal heart attack due to the earthquake. Most people were in bed and the streets were almost deserted. The lack of casualties was also due to strict building regulations and partial strengthening of many older buildings.
The worst damage was suffered by older (mainly pre-1940s) buildings constructed of brick and masonry, and lacking adequate reinforcement. Some walls crumbled, with bricks cascading onto the streets. Brick chimneys toppled through tile roofs. A falling chimney caused one of the few serious injuries. A number of historic stone churches were badly damaged, although both the Anglican and Catholic cathedrals suffered only minor cracking. An early Treasury estimate of the cost of the earthquake was $4 billion.
The Greendale Fault
A fault rupture occurred along a previously unknown fault line, which was named the Greendale Fault. Movement along the fault broke the surface, creating a fault trace extending for 30 kilometres west from Rolleston. Roads, fences, shelter belts and irrigation channels were offset sideways by up to 5 metres, with up to 1.3 metres vertical offset. The area north of the fault rupture moved eastwards and the area south of it westwards.
Aftershocks continued for several months after the earthquake, some strong enough to cause damage to already-weakened structures. The aftershocks were mainly clustered along the Greendale Fault, reflecting gradual readjustment of the earth’s crust to a major rupture. Aftershocks at the eastern end of the Greendale Fault, close to Christchurch, were felt particularly strongly.
Liquefaction and lateral spreading
The earthquake’s shaking turned water-saturated layers of soft sand and silt into liquid mush, a process known as liquefaction. The most badly affected areas were close to the coast, especially the town of Kaiapoi and the Christchurch suburb of Bexley, where a number of modern houses were damaged. The ground above the liquidised layers subsided unevenly, cracking footpaths, roads and houses. Water and sewer pipes broke, leading to local flooding. Silty sludge squirted up through cracks to produce small sand volcanoes.
Cracks opened up close to rivers and streams where the ground moved down towards the water, causing damage to man-made structures – a process known as lateral spreading.
The 2011 Christchurch earthquake
On Tuesday 22 February 2011 at 12.51 p.m. Christchurch was badly damaged by a magnitude 6.3 earthquake, which killed 185 people and injured several thousand. The earthquake epicentre was near Lyttelton, just 10 kilometres south-east of Christchurch’s central business district. The earthquake occurred more than five months after the 4 September 2010 earthquake, but is considered to be an aftershock of the earlier quake.
Casualties and damage
One hundred and eighty five people died as a result of the 22 February earthquake. It was lunchtime and many people were on the city streets. One hundred and fifteen died in the CTV building, 18 in the PGC building, 36 in the central city (including eight on buses), and 12 in the suburbs (including from falling rocks in the Redcliffs, Sumner and Port Hills). The Chief Coroner determined that another four deaths were directly associated with the earthquake. (A complete list of the deceased can be found on the New Zealand Police website.)
The earthquake brought down many buildings previously damaged in the September 2010 earthquake, especially older brick and mortar buildings. Many heritage buildings were heavily damaged, including the Provincial Council Chambers, Lyttelton’s Timeball Station, and both the Anglican Christchurch Cathedral and the Catholic Cathedral of the Blessed Sacrament. Among the modern buildings damaged, and eventually demolished, was Christchurch’s tallest building, the Hotel Grand Chancellor. Over a quarter of the buildings in the central business district were demolished.
A violent earthquake
Although not as powerful as the magnitude 7.1 earthquake on 4 September 2010, this earthquake occurred on a fault line that was shallow and close to the city, so the shaking was particularly destructive. In the February 2011 quake, the fault movement and structure of the bedrock produced exceptionally strong ground motion – up to 1.8 times the acceleration due to gravity in the eastern suburbs. In the city centre ground accelerations were three to four times greater than those produced by the September 2010 earthquake.
Liquefaction
Liquefaction was much more extensive than in the September 2010 earthquake. Eastern sections of the city were built on a former swamp. Shaking turned water-saturated layers of sand and silt beneath the surface into sludge that squirted upwards through cracks. Properties and streets were buried in thick layers of silt, and water and sewage from broken pipes flooded streets. House foundations cracked and buckled, wrecking many homes. Despite the damage to homes, there were few serious injuries in residential houses in liquefaction areas. However, several thousand homes had to be demolished, and a large area of eastern Christchurch will probably never be reoccupied.
Aftermath and exodus
The government activated its National Crisis Management Centre immediately and declared a national state of emergency the day after the quake. Christchurch’s central business district remained cordoned off for more than two years after the earthquake. Electricity was restored to 75% of the city within three days, but water supplies and sewerage systems took several years to restore in some areas affected by liquefaction.
In the weeks following the earthquake about 70,000 people were believed to have left the city due to uninhabitable homes, lack of basic services and continuing aftershocks. Timaru’s population swelled by 20% and thousands of pupils registered at schools in other cities and towns. Many returned to Christchurch as conditions improved.
Fault beneath the Port Hills
The earthquake was caused by the rupture of a 15-kilometre-long fault along the southern edge of the city, from Cashmere to the Avon–Heathcote estuary. The fault slopes southward beneath the Port Hills and did not break the surface – scientists used instrument measurements to determine its location and movement.
Marlborough earthquakes – 2013 and 2016
2013 Cook Strait and Lake Grassmere earthquakes
At 5.09 p.m. on Sunday 21 July 2013, a magnitude 6.5 earthquake rocked central New Zealand, causing minor damage. The earthquake was centred in Cook Strait, about 20 kilometres east of Seddon. In Wellington, plate glass fell from some downtown buildings. The following day much of the central city was closed for business as buildings were assessed for structural damage.
The period of seismic activity continued with a 6.6 magnitude quake at 2.31 p.m. on Friday 16 August. Centred near Lake Grassmere, the quake damaged buildings in Seddon and nearby towns and some buildings in Wellington.
2016 Kaikōura earthquake
At 12.02 a.m. on Monday 14 November 2016, a magnitude 7.8 earthquake, the second strongest quake since European settlement, shook the eastern coast of the northern South Island. Lasting for nearly two minutes, the complex earthquake started near Culverden, then moved north-east, jumping between at least 21 faults, both onshore and offshore, along 180 kilometres of the Marlborough coast.
The shaking brought down tens of thousands of landslides from the mountains. Two people died, one in the collapse of a homestead near Kaikōura and one from a head injury.
Damage to urban areas
Blenheim, Ward, Kaikōura, Waiau, Hanmer Springs, Cheviot, Culverden and other small towns in the region had substantial damage.
Strong shaking in the Wellington area damaged port facilities and many office buildings. Thousands of workers had to work from home or relocate to new offices as damaged buildings were inspected, and either demolished or closed for repairs.
Landslides and damage to roads and railways
Between 80,000 and 100,000 landslides were triggered by the earthquake and aftershocks, burying sections of State Highway 1 and the main trunk railway line and isolating the town of Kaikōura. Some landslides blocked rivers and streams, creating about 200 landslide-dammed lakes. The earthquake damage disrupted overland transport between Picton and Christchurch, halting train travel and necessitating detours of nearly 140 kilometres for road traffic.
Kaikōura town
More than 600 tourists were stranded at Kaikōura. Some 450 were evacuated to Lyttelton aboard HMNZS Canterbury and 165 on New Zealand Defence Force helicopters. The military also delivered food, water and other supplies to the town. State Highway 1 reopened between Kaikōura and Christchurch in December 2016, and between Kaikōura and Blenheim a year later.
A changed coast
During the Kaikōura earthquake, large areas of the South Island’s northeastern coast shifted upward and northward. Cape Campbell moved 5 metres closer to the North Island. The greatest amount of uplift measured was 8 metres, while the largest horizontal movement was 12 metres.
The Marlborough coast generally was raised between 0.5 and 2 metres from about 20 kilometres south of Kaikōura to Cape Campbell. Uplift of large swaths of the seabed left marine life such as pāua and crayfish exposed.
Tsunami
Several submarine faults ruptured, triggering minor tsunami. Hundreds of people moved to higher ground in Kaikōura and cities such as Wellington and Christchurch.
Because of uplift of long stretches of the coast and the fact that it was low tide in the area, the effects were minor. The maximum tsunami height, 6–7 metres, was at Goose Bay, with 2.5-metre waves at Kaikōura and 1.6 metres at Wellington. At Little Pigeon Bay on Banks Peninsula, a 3-metre wave pushed a holiday house off its foundations.
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