· ·

Very strong and shallow M7.5 earthquake hits New Caledonia, tsunami waves observed


A very strong earthquake registered by the USGS as M7.5 hit south of the Loyalty Islands, New Caledonia at 04:18 UTC on December 5, 2018. The agency is reporting a depth of 10 km (6.2 miles). EMSC is reporting M7.6 at a depth of 30 km (18.6 miles).

According to the USGS, the epicenter was located 168 km (104 miles) ESE of Tadine and 254 km (158 miles) ESE of We, Loyalty Islands, New Caledonia.

There are no people living within 100 km (62 miles).

Some 3 000 people are estimated to have felt moderate shaking, 154 000 light, and 206 000 weak.

The quake was preceded by M6.0 at 04:14 UTC and followed by M5.9 at 04:28 UTC, M5.9 at 04:30, M5.6 at 04:31, M4.9 at 04:41, M5.7 at 04:41, M5.3 at 04:50, M5.2 at 04:54, M4.9 at 06:36, M6.6 at 06:43, M4.9 at 06:51, M5.1 at 07:45, M5.2 and 07:46 and another M5.2 at 08:01.

18 more earthquakes were registered by 16:37 UTC, magnitudes ranging from 4.4 to 5.5.

Aftershocks continue shaking the region.

Tsunami waves have been observed following M7.5 quake at 04:18 UTC, PTWC said.

Based on all available data, hazardous tsunami waves are forecast for some coasts, the center said.

Tsunami waves reaching 1 to 3 m (3 – 10 feet) above tide level are possible along some coasts of New Caledonia and Vanuatu.

Tsunami waves reaching 0.3 to 1 m (1 – 3 feet) above tide level are possible for some coasts of Fiji.

There are no reports of casualties or damage. An evacuation order is in effect for areas within 300 m (984 feet) of the east coast of Grande Terre Island, the Isle of Pines and the Loyalty Islands.

The tsunami warning was lifted at 07:09 UTC.

“Based on all available data, the tsunami threat from this earthquake has now largely passed, PTWC said. “Government agencies responsible for any impacted coastal areas should monitor conditions at the coast to determine if and when it is safe to resume normal activities. Persons located near impacted coastal areas should stay alert for information and follow instructions from local authorities. Remain observant and exercise normal caution near the sea.”

Minor sea level fluctuations of up to 0.3 m (1 feet) above and below normal tide may continue over the next few hours.

The following are tsunami wave observations from coastal and/or deep ocean sea level gauges at the indicated locations. The maximum tsunami height is measured with respect to the normal tide level.

Gauge LocationLatitudeLongitudeTime (UTC)Maximum Wave Height (M/FT)Tsunami Period (Min)
Suva, Viti Levu, FJ18.1S178.4E06520.03M/ 0.1FT38
Numbo, New Caledonia22.2S166.4E06130.04M/ 0.1FT06
Thio, New Caledonia21.6S166.2E06310.23M/ 0.8FT12
Vanuatu17.8S168.3E06010.30M/ 1.0FT18
Hienghene, New Caledonia20.7S164.9E05570.09M/ 0.3FT22
Ouinne, New Caledonia22.0S166.7E05540.45M/ 1.5FT06
Lifou, New Caledonia20.9S167.3E05220.29M/ 1.0FT06
Mare, New Caledonia21.5S167.9E05190.43M/ 1.4FT10
Lenakel, VU19.5S169.3E05050.72M/ 2.4FT06

As of 07:30 UTC, the maximum measured heights are: 0.72 m (2.3 feet) in Lenakel town (Tanna Island, Vanuatu); 0.45 m (1.47 feet) in Ouinne (south-eastern Grande Terre Island, New Caledonia), 0.43 m (1.41 feet) in Maré Island, 0.29 m (0.94 feet) in Lifou Island (New Caledonia) and 0.15 m (0.49 feet) in Thio (south-eastern Grande Terre Island). 

The USGS issued a green alert for shaking-related fatalities and economic losses. There is a low likelihood of casualties and damage.

Overall, the population in this region resides in structures that are highly vulnerable to earthquake shaking, though some resistant structures exist. The predominant vulnerable building types are unknown/miscellaneous types and wood construction.

Recent earthquakes in this area have caused secondary hazards such as tsunamis that might have contributed to losses.

Estimated population exposure to earthquake shaking

Selected cities exposed

Regional seismicity

Featured image credit: Google, USGS, TW


Commenting rules and guidelines

We value the thoughts and opinions of our readers and welcome healthy discussions on our website. In order to maintain a respectful and positive community, we ask that all commenters follow these rules:

  • Treat others with kindness and respect.
  • Stay on topic and contribute to the conversation in a meaningful way.
  • Do not use abusive or hateful language.
  • Do not spam or promote unrelated products or services.
  • Do not post any personal information or content that is illegal, obscene, or otherwise inappropriate.

We reserve the right to remove any comments that violate these rules. By commenting on our website, you agree to abide by these guidelines. Thank you for helping to create a positive and welcoming environment for all.

One Comment

Leave a reply

Your email address will not be published. Required fields are marked *