A large magnitude shallow earthquake has caused strong shaking and fatalities from widespread destruction in Vanuatu.
The quake struck 37km from the capital, Port Vila, and an initial tsunami warning has since been lifted.
Update 19 Dec: New Zealand aid flights are arriving in the Pacific Island nation, as the search for survivors continues, and hundreds of wounded are treated.
The SMC asked experts to comment.
Prof Mark Stirling, Chair of Earthquake Science, University of Otago, comments:
“This earthquake occurred at ground zero of one of the most active plate boundaries in the world.
“The subduction zone between the Vanuatu microplate and Australian plate is moving extremely fast (about 170 mm/yr), so major earthquakes are commonplace there.
“This earthquake was at nearly 60 km depth and magnitude 7.3 according to the US Geological Survey, which means it was significantly smaller than the magnitude >8 tsunami-generating earthquakes that can occur there.
“An earthquake of today’s magnitude would have to have occurred in the shallow crust (<20km) to produce a damaging local tsunami. What it did produce was damaging high frequency shaking, based on the observed building damage.”
No conflicts of interest declared.
Leina Isno (Ni – Vanuatu), PhD student, Centre for International Health, University of Otago; and Health Research Council of New Zealand Pacific Clinical Research Training Fellowship Candidate comments:
Note: Leina, an Operating Theatre Nurse with experience in humanitarian work for the International Red Cross, is currently researching scrub typhus (Orientia tsutsugamushi) a neglected infectious bacterial disease in northern Vanuatu. She divides her time between New Zealand, Vanuatu and Thailand.
“It’s been six days since a powerful 7.3 magnitude earthquake struck Port Vila, Vanuatu, triggering more than 300 aftershocks, including a few as strong as 6.3 magnitude. The constant tremors have left many people feeling stressed and unsettled. Rescue teams are focused on helping those affected by the quake, but the latest aftershock, which happened early on Sunday, December 22, along with heavy rain forecasts, is adding more pressure to an already difficult situation.
“The Port Vila Base Hospital is under immense strain due to ongoing shortages of doctors, nurses, and other health staff. If the hospital building itself is damaged, it could become even harder to provide critical care for those injured in the earthquake and manage morgue space for the deceased.
“The scale of the damage and the number of injured people may be overwhelming, especially for locals who are still recovering from the destruction caused by Tropical Cyclone Pam in 2015, as well as more recent cyclones Harold, Lola, and the twin storms Judy and Kevin. With each disaster, the community faces more challenges in rebuilding and recovering.
“In addition to the physical damage from the earthquake, Port Vila is also facing unpredictable weather, including heavy rains that will likely cause flash flooding. The city’s aging infrastructure and poor drainage systems make the downtown area especially vulnerable. This flooding can create ideal conditions for the spread of diseases, particularly in overcrowded communities where sanitation is already a problem. Bacterial infections, like leptospirosis, are a major concern in these conditions.
“Disasters also create new environments where diseases can spread. High heat and humidity, close contact between people and animals, and the constant movement of people between islands increase the chances of disease outbreaks. We are seeing the return of hundreds of Recognised Seasonal Workers from New Zealand for the festive season. The earthquake has only made these challenges worse by displacing many people and worsening already poor living conditions.
“Another major concern is the emotional toll on the population. The stress caused by the ongoing disasters can lead to increased violence, especially against women and animals.
“Mental health is a significant issue, but it remains stigmatized, making it difficult for people to seek help. Many may turn to traditional coping mechanisms, like consuming kava (Piper methysticum) in our nakamals (drinking spaces), a natural sedative, as there is a shortage of mental health professionals to provide proper care.
“Certain groups, such as pregnant women, young children, the elderly, and disabled individuals, need special attention during disasters like this, as they are more vulnerable.
“The earthquake has also caused landslides along the coast, where Vanuatu’s international ports and terminals are located. The steep, unstable hills on Efate Island, combined with aftershocks and rain, make the situation even more dangerous. The challenges include:
- Flash flooding and soil erosion that impact the marine environment, threatening the local food supply.
- Contaminated water supplies caused by unstable water tanks on the hills, leading to water shortages.
- Increased interactions between people and animals, such as insects and rodents, which thrive in damp conditions. These animals can spread diseases, and the risk of infections like malaria, dengue fever, and Hepatitis A will likely increase in the coming months.
“The Port Vila Base Hospital is expected to see a rise in cases of fever, fungal infections, and diseases spread by animals and insects. With the hospital’s health system already weakened by the earthquake, it will be even more difficult to manage disease outbreaks and provide necessary care because of the limited diagnostics and treatment capabilities, further complicating disease control and health prevention efforts.
“Rescue efforts are taking a toll on local volunteers, who are working tirelessly to save lives under extremely challenging conditions. These efforts will require additional mental health support for the local organizations involved, like ProRescue and ProMedical.
“As Vanuatu continues to deal with these disasters, there is an urgent need to build local capacity for disaster response and create a more self-sustainable community that can better handle future crises.”
No conflicts of interest.
Dr John Ristau, GNS Seismologist, comments:
“Vanuatu is a highly seismically active region as much of the South Pacific islands are, and large earthquakes are not uncommon, with 30 magnitude 7+ earthquakes in the last 25 years.
“The recent earthquake was close to the most populated of Vanuatu’s islands and its capital, Port-Vila. In this region the Australian tectonic plate is pushing (subducting) beneath the Pacific plate and this earthquake occurred within the Australian plate. Seismologists call this an intraplate earthquake. Intraplate earthquakes often produce strong, high frequency shaking, which is the type of shaking most damaging to buildings.
“The proximity to Port-Vila and the strong, high frequency shaking were the main contributing factors to the extensive damage. There have been numerous reports of collapsed buildings and more widespread structural damage. The collapse of buildings in Port-Vila and other population centres could be like what Christchurch experienced in February 2011.
“The USGS has located 14 aftershocks with the largest being two M 5.5 earthquakes; however, there will have been many smaller aftershocks that the USGS hasn’t located. There is also the possibility for a larger aftershock(s) of M 6+, and even a small chance (~5%) of a similar size or larger earthquake in the coming days. Aftershocks that are smaller than the mainshock can still cause considerable damage to buildings weakened by the mainshock, so people need to be prepared and cautious. Those in New Zealand who experienced significant earthquakes, e.g., Canterbury, Kaikōura, will be aware that aftershock sequences can continue for weeks, months, or even years. Vanuatu citizens should listen to relevant government and scientific advice on how best to prepare for and deal with aftershocks.
“There was a small tsunami (~30 cm) recorded in Vanuatu, but no significant impacts that we are aware of. In New Zealand, GNS Science worked closely with the National Emergency Management Agency (NEMA) to assess the tsunami threat to New Zealand and keep the public informed. After careful analysis it was determined there was no tsunami threat to New Zealand.“
No conflicts of interest declared.
Professor Siautu Alefaio, Professor of Psychology, University of Otago, comments:
“Our thoughts and prayers are with the people of Vanuatu as they face the aftermath of this earthquake. For those affected, the fear and uncertainty of not being able to communicate with loved ones is one of the hardest challenges, especially during the festive season when families are preparing for celebrations.
“For the Vanuatu diaspora in New Zealand, including seasonal workers, timely communication is critical. While official government emergency responses are in place, the role of the diaspora in supporting their families is already in motion. Many have established remittance and support networks, which are vital in the immediate aftermath. Keeping them informed is crucial, as they will continue to play a significant role in disaster recovery long after emergency responders have left.
“The response of the Tonga diaspora during the Hunga Tonga-Hunga Haʻapai volcanic eruption highlights the importance of diaspora-driven support. Despite communication disruptions, their swift action demonstrated the resilience of community-based humanitarianism. Keeping diasporic communities in the loop is vital to sustaining long-term disaster recovery efforts.
“Diasporic humanitarianism, often an invisible and community-led response, is a key driver of post-disaster recovery. Our study highlights this critical, yet often overlooked, role played by diaspora communities in supporting the rebuilding process long after emergency responders have left.
“In the wake of this disaster, it is essential to recognize the vital contributions of Vanuatu’s diaspora, who are already supporting their families back home and will continue to do so in the months and years to come.”
No conflicts of interest declared.
Dr Lauren Vinnell, Lecturer of Emergency Management, Joint Centre for Disaster Research, Massey University, comments:
“First and foremost, my thoughts are with those in Vanuatu as they continue looking for those missing, helping those injured, and otherwise processing what this earthquake means for them. Vanuatu is a country which unfortunately has experienced its fair share of disasters. As is the case with any community who has been impacted repeatedly, we need to be careful not to assume they will be ‘resilient’ in this latest event, just because they’ve been through it before. Previous experience can increase your resilience, but it can also decrease it. Often people are able to cope because there is no choice – we should be aiming higher, for “coping well“. I hope that those in the affected areas of Vanuatu receive all the support they need in order to cope well and recover quickly and fully from this earthquake.
“Earthquakes are a particularly distressing event because they usually involve aftershocks. As well as being able to cause further damage and injury, they act as a constant reminder of the awful main earthquake and make it even harder to deal with all of those strong emotions which people will be feeling like fear, anxiety, and anger. There’s some great work happening around the world, including in NZ, to train response workers in how to help people who have been affected to process their emotions, but as we see time and again here and overseas there is usually not enough resource put towards helping people manage the psychological impacts of disasters.
“There are significant communication challenges in this event, as a result of damage to networks like phone and power. This is not a problem we’re immune to here in NZ, as we saw during Cyclone Gabrielle. Being able to get information from impacted areas quickly is absolutely vital for responding well. Some parts of the country are really stepping up to this challenge, but this needs to continue to be a matter of urgency.”
No conflicts of interest
Dr Michelle McCrystall, climate scientist, University of Auckland, comments:
Note: Dr McCrystall has been researching the impact of extreme weather events on the health infrastructure of Melanesian islands.
“I did visit the main hospital Vila Central when I was in Vanuatu last year, and they were completely over capacity.
“Hospital facilities in Vanuatu are already stretched with limited resources and lack of good medical equipment and are making do with second hand equipment for the health provisions for the entire country.
“So the deaths and injuries will stretch an already thin health industry that requires more nurses and doctors to provide adequate health care as well as substandard health equipment.
“Providing not only better equipment but the training to the nurses and doctors in Vanuatu to operate these machines and providing additional medical personnel to aid with the additional stress will be a huge benefit to Vanuatu in this instance but also in the future in the face of additional natural disasters that may occur.
“These are my opinions of the situation in Vanuatu based on what I had seen and what had been told to me when I was there by the medical staff at the hospital.”
No conflicts of interest declared.
Dr Ian de Terte, Associate Professor/Clinical Psychologist, School of Psychology, Massey University, comments:
“The earthquake in Vanuatu is tragic for the residents of that country. As a country they have had several disasters in the last decade. I understand that hundreds have been injured and the number of confirmed deaths from this event is still rising. My thoughts are with them. Over the next few days and weeks there will be support for the residents of Vanuatu. This will be in the form of people from aid organisations, police officers, and military personnel, to name a few.
“The people from the support agencies need to manage themselves so they are performing to the best of their ability. When people are there in a support role there is a tendency for some people to overwork, but it is vitally important for the “helpers” to look after themselves so that they work to the best of their ability. It is only natural for people who have gone there to assist the locals to work long hours, but it is vitally important for these “helpers” to look after themselves. I would encourage the leaders or managers of these groups to ensure that the “helpers” have all the resources they require, stay at clean and tidy accommodation, and are ably resourced, so they can stay hydrated and maintain a healthy diet. Some things that “helpers” can do to maintain this balanced approach is to ensure they exercise regularly, get enough sleep, and limit their alcohol intake. If this occurs then the “helpers” will be at the top of their game.”
Conflict of interest statement: “Ex-member of the New Zealand Police.”
Associate Professor Kasper van Wijk, Department of Physics, University of Auckland, comments:
“Vanuatu is situated, like New Zealand, on top of a subduction zone. This particular earthquake was shallow and close to Port Vila, so I expect there to be significant damage from the earthquake.
“From recordings of the seismic waves, it appears this earthquake could also have the ingredients for a tsunami, specifically for the Islands in the region. The hypocentre was in the crust overlain by the Pacific Ocean, and there may have been the rapid uplift of the crust under the water needed for a tsunami.”
No conflicts of interest declared.
Dr Ulrich Speidel, Senior Lecturer, School of Computer Science, University of Auckland, comments:
“I understand from RNZ that the cable landing station in Port Vila is damaged but that the cable as such is intact, which is good news as long as the landing station damage can be fixed. It means they won’t need to bring a cable ship in, which could take weeks.
“The picture on the local comms network isn’t clear – disasters such as these tend to overload whatever is there even if there is no damage. But given that there are a number of large buildings that have come down, it’s likely that at least a few cell sites – which often sit on such buildings – have also gone down with them. Local wired infrastructure is likely to be damaged also and could take some time to fix.
“Starlink does work as it’s not reliant on ground infrastructure in Vanuatu (except power – but that could come from a generator), but capacity there is somewhat limited, so I’d recommend people there to restrict use of whatever works to essential comms only.”
No conflicts of interest declared.
Mary Anne Clive, GNS Hazard and Risk Social Science Team Leader, comments:
“Large damaging earthquakes and their ongoing aftershocks can result in significant distress and have substantial impacts on the mental health and wellbeing of people that are affected. Recovery from these devastating events can be complex and long-term.”
No conflicts of interest declared.
Our colleagues at the Australian Science Media Centre also gathered comments:
Dr Behzad Fatahi is Professor of Civil Engineering at the University of Technology Sydney
“Vanuatu, a Pacific island nation of over 80 islands and a population of approximately 320,000, sits in the highly seismically active “Ring of Fire”. Port-Vila, with a population of around 50,000, is the closest major urban area to the epicentre and likely experienced the strongest impacts. The earthquake occurred approximately 1,800 km east of the northeastern coast of Australia (e.g., Cairns, Queensland). Nearby regions, including New Caledonia (southwest), Fiji (to the east), and the Solomon Islands (northwest), remain at risk of tsunami activity and should remain vigilant.
“This earthquake occurred where the Australia Plate subducts beneath the Pacific Plate at a rate of about 85 mm/year, in one of the most seismically active zones in the world.
“Aftershocks can be serious and sometimes nearly as dangerous as the main event. As of 4PM Sydney time, when this report is written, 58 earthquakes have struck the region, with five of them exceeding magnitude 5.0. In 2009, two powerful earthquakes (Mw 7.7+) struck this region within 15 minutes of each other, and in 2021, the Loyalty Islands earthquake triggered multiple smaller earthquakes and tsunamis. These events highlight the potential for aftershocks or additional strong earthquakes in the coming hours or days. Residents in Port-Vila, as well as nearby regions like New Caledonia, Fiji, and the Solomon Islands, should remain alert for further shaking.
“It is expected that this very strong ground motion near Port-Vila has caused cracks in masonry walls, foundation instability, and tilting of vulnerable structures, especially in areas with soft soil. Temporary structures, old historical buildings, and shelves in shops may have become unstable, and inspectors need to carefully assess these during post-earthquake inspections to ensure safety. Secondary hazards, such as soil liquefaction and landslides, are also concerns, particularly in coastal cliffs and hilly areas west of Port-Vila, where ground instability could worsen with aftershocks.”
Fabio Capitanio is Associate Professor in Geophysics and Computational Geodynamics within the School of Earth, Atmosphere and Environment at Monash University
“The earthquake striking Vanuatu occurred on a very well known subduction zone, where the Indo-Australia tectonic plate subducts beneath the Pacific Plate. The magnitude of this earthquake, that is, the energy released, is comparable to the explosion of Mt. St. Helens in 1980.
“The recurrence time of these earthquakes is estimated to be around every ~100 years and, although we have evidence of shorter recurrence times elsewhere, e.g., southeast Asia, the Vanuatu record is consistent with this estimate, although this cannot be used as a future projection.
“Events of similar magnitude are associated with the risk of tsunami, however the historical record shows low tsunami occurrence, as it seems in this very case. The damage associated to such high energy earthquakes is expectedly large, although this area has a record of low seismic damage.”
Professor Meghan Miller is an ARC Future Fellow and Director of the AuScope Earth Imaging Program in the Research School of Earth Sciences at the Australian National University
“On December 17, 2024, a magnitude 7.3 earthquake occurred at the boundary between the Australia and Pacific plates near Vanuatu. In this region, where the tectonic plates converge is one the world’s most seismically active plate boundaries. The earthquake hypocentre was fairly deep, about 57 km, which means there was no tsunami generated. However, the capital city Port Vila is located only ~30 km away from the epicentre, and the island experienced very strong shaking, likely resulting in moderate damage to structures.”
Adam Pascale is the Chief Scientist at the Seismology Research Centre earthquake observatory
“Not all offshore large magnitude earthquakes generate a tsunami, due to reasons such as earthquake depth and the orientation of the rupture of the fault. It is prudent to issue tsunami warnings if predetermined criteria are met, and equally important to clear warnings once there is evidence that the threat of tsunami is no longer active.
“This occurred two weeks ago when a magnitude 7.0 earthquake occurred off the coast of California, and again today for the magnitude 7.3 earthquake that struck just off the coast of Port-Vila, Vanuatu.
“I explored tsunami warnings in a short TikTok video a week ago. In today’s earthquake, it was more likely the depth of the event rather than the type of rupture that prevented the tsunami being generated.”