2016 Kaikoura earthquake

2016 Kaikoura earthquake

Date	14 November 2016
Origin time	00:02:56 NZDT
Magnitude	7.8 Mw[1][2]
Depth	15 km (9 miles)
Epicenter	42°45′25″S 173°04′37″E / 42.757°S 173.077°E / -42.757; 173.077Coordinates: 42°45′25″S 173°04′37″E / 42.757°S 173.077°E / -42.757; 173.077 15 km (9 miles) north-east of Culverden
Areas affected	New Zealand
Max. intensity	IX (Violent)[1]
Tsunami	Yes
Aftershocks	> 7,000[3] (as of 2 December)
Casualties	2 dead[4] 57 treated for injuries[5]

Map of Kaikoura earthquakes

USGS ShakeMap for the event

The 2016 Kaikoura earthquake was a magnitude 7.8 (M_w) earthquake in the South Island of New Zealand that occurred two minutes after midnight on 14 November 2016 NZDT (11:02 on 13 November UTC).^[1] The epicentre where shaking started was about 15 kilometres (9 mi) north-east of Culverden and 60 kilometres (37 mi) south-west of the tourist town of Kaikoura and at a depth of approximately 15 kilometres (9 mi).^[2][6][7][8] However, the earthquake ruptured on multiple fault lines in a complex sequence that lasted for more than one minute and its cumulative magnitude was 7.8, with the majority of that energy released far to the north of the epicentre.^[9][10] The large magnitude of the quake makes it one of the world's three largest earthquakes in 2016, and second in magnitude to only one New Zealand earthquake since European settlement of the country.^[11] Casualties were reported in Culverden and Kaikoura.^[4][12] There were two deaths, in Kaikoura and Mount Lyford.^[12]

Earthquake

The complex sequence of ruptures with a combined magnitude of 7.8 struck at 00:02:56 NZDT on 14 November 2016, 15 kilometres (9 mi) north-east of Culverden and 95 km (59 mi) from Christchurch.^{[10][12][13][14]} According to GNS Science,^[15] while the rupture started at the epicentre, the earthquake progressed northwards, travelling at a speed of 2 km per second, over a length of up to 200 km (124 mi). The complexity of the earthquake was such that the largest amount of energy released did not occur at the epicentre, rather 100 km (62 mi) to the north near Seddon. Field surveys indicate ruptures on at least six faults.^[16]

There was motion on the Kekerengu Fault of up to 10 m (33 ft), movement on the Hundalee Fault, a newly identified fault in Waipapa Bay, as well as minor motion on the Seaward segment of the Hope Fault,^[13] and rupture on the Humps Fault and in the Emu Plains area.^[16] Portions of seabed near Kaikoura were lifted at least 2 m (7 ft) along the shore, creating new coastline.^[17] The offshore continuation of the Kekerengu Fault to the north east, known as the Needles Fault, ruptured as well. NIWA marine geologist Dr Philip Barnes said the length of the Kekerengu–Needles Fault rupture may extend for about 70 km (43 mi), consisting of 36 km (22 mi) on land and 34 km (21 mi) under the sea.^[18]

Tsunami

At 01:32 (NZDT) on 14 November the Ministry of Civil Defence & Emergency Management (MCDEM) issued a tsunami warning for the eastern coasts of the North and South Islands and the Chatham Islands.^[19]

A wave of 2.5 m (8.2 ft) was recorded at Kaikoura, 1 m (3 ft) at Christchurch, and 0.5 m (1.6 ft) at Wellington.^[20] A wave of 0.2 m (0.7 ft) was recorded in Napier at about 3 am.^[21] A tsunami estimated at five metres high struck the north-facing Little Pigeon Bay on Banks Peninsula.^[22] The bay contained only one building, an unoccupied holiday house that was pushed off its foundations and heavily damaged.^[23] In neighbouring Pigeon Bay the tsunami was observed at about 2 am but caused no damage.^[22]

Casualties and damage

Kaikoura and North Canterbury

The Elms homestead, pictured here in 2012, collapsed during the earthquake, killing one person.

Two deaths were reported: one person suffered a heart attack, while the other was crushed when the historic Elms Farm homestead near Kaikoura collapsed. Two people were rescued from the rubble of the house, including the victim's 100-year-old mother.^[24]

Many major roads were closed in the South Island because of slips and damage to bridges, including State Highway 1 between Picton and Waipara, and State Highway 7 between Waipara and Springs Junction (SH 65 turnoff). Most roads were cleared within 24 hours, but SH 1 between Seddon and Cheviot via Kaikoura and the Inland Kaikoura Road remained closed.^[25] The closure of SH1, the Inland Kaikoura Road and the Main North Line railway effectively cut off all land routes into Kaikoura.^[26][27]

Police arrested three young men after receiving a report on 16 November that a freight train abandoned between two landslides had been looted.^[28]

As of the morning of 19 November, Kaikoura remained cut off by road due to landslides, damaged bridges and infrastructure, road subsidence, and the risk of falling debris.^[29] The NZTA said that State Highway 1 would take months to repair, while repairs to the rail line, a key freight connection between Wellington and Christchurch were likely to take more than a year.^[30] The diversion route via State Highways 63, 6, 65 and 7 was experiencing four times its usual traffic volumes.^[31]

Mains water supply was mostly restored to Kaikoura township by 19 November, but supply was in a "fragile state" and conservation was necessary. The sewage system was "severely damaged" and unusable.^[32]

On 30 November 2016, the Inland Kaikoura Road, redesignated "Kaikoura Emergency Access Road", was reopened to civilian drivers holding a permit and for restricted times of the day. Twenty-five crews had worked to clear 50 landslips on that highway alone.^[33]

Wellington

Widespread damage to buildings occurred in the city of Wellington, with power outages affecting many communities. A high-rise office block on Molesworth Street in Wellington was cordoned off after the quake amidst fears that it could collapse.^[34] Demolition of the nine storey building began on 28 November.^[35] The Queensgate Shopping Centre in Lower Hutt was closed after the quake for urgent inspection. It partially reopened on 25 November, however one part of the centre containing a cinema complex and carpark was deemed unsafe and is scheduled to be demolished.^[36]

Damage to docks at Wellington also impaired ferry traffic across the Cook Strait.^[21]

Christchurch

One house in the coastal suburb of New Brighton in Christchurch was reportedly looted after the occupants left because of tsunami risk.^[37]

Regional effects

Schools and universities across the region were told to remain closed until the situation could be assessed,^[38][39] affecting the end-of-year NCEA examinations for secondary school students.^[40]

Response

Prime Minister John Key surveyed the damage from the air and later described the scenes as "utter devastation" and estimated that reconstruction would take months and cost billions of dollars.^[41]

The New Zealand Defence Force dispatched five Royal New Zealand Air Force helicopters (four NH90s and one Agusta A109 from RNZAF Base Ohakea, a P-3 Orion, and a C-130 Hercules from RNZAF Base Whenuapai. The aircraft were tasked to survey and provide essential emergency supplies to the most-severely affected areas around Kaikoura. Kaikoura Aerodrome was too small to take larger multi-engine aircraft so landing was limited to helicopters and small aircraft. The Royal New Zealand Navy's multi-role vessel HMNZS Canterbury and off-shore patrol vessel HMNZS Wellington were deployed to Kaikoura to provide aid supplies and evacuate people.^[42] HMCS Vancouver, HMAS Darwin and USS Sampson, in New Zealand waters for the RNZN's 75th birthday celebrations in Auckland, were redirected by their respective governments to assist.^[43] A United States Navy P-3 Orion of VP-47 and two Japan Maritime Self-Defense Force Kawasaki P-1s, also visiting RNZAF Base Whenuapai for the RNZN 75th anniversary events,^[44] were deployed to assist.^[45] The New Zealand Defence Force also deployed HMNZS Te Kaha and HMNZS Endeavour to support the operation.

The New Zealand Fire Service dispatched urban search and rescue teams to Wellington and Kaikoura. Paramedics were also dispatched from St John.^[38]

Baggage of evacuees being unloaded off HMNZS Canterbury

Nearly 200 people had been airlifted out of Kaikoura by late evening on 15 November, with about 1,000 still to be evacuated on the following morning.^[46] Stranded tourists with health issues and travel plans were put on a flight priority list.^[47] HMNZS Canterbury arrived in Kaikoura on 16 November and transported about 450 evacuees, 4 dogs, and 7 tonnes of luggage to Lyttelton, arriving early the following morning.^[48]

On the morning of 20 November, HMNZS Canterbury arrived at Lyttelton with another group of evacuees, bringing the total number evacuated from Kaikoura to more than 900.^[32]

Aftershocks

• 

  Magnitude of Kaikoura earthquakes

• 

  Number of aftershocks within 200 km of Kaikoura

See also

• List of earthquakes in 2016
• List of earthquakes in New Zealand
• Marlborough Fault System
• Tsunamis affecting New Zealand

References

External links

• Measuring uplift along the Kaikoura coast – GNS Science