The Landslide Blog is written by Dave Petley, who is widely recognized as a world leader in the study and management of landslides.
It has been widely reported that an M=7.3 earthquake struck Vanuatu on 17 December 2024 at 12:47 local time. Wikipedia is referring to this as the Port Vila Earthquake as the epicentre was located offshore of this city. At the time of writing, there were 14 confirmed fatalities and 200 injuries, although the picture remains unclear.
The island mostly affected by the earthquake – Efate – has some steep slopes (the highest peak extends to c.650 metres), and coastal cliffs, so it is not surprising that there have been some landslides. The most prominent have occurred on abandoned coastal cliffs close to the port. The following Youtube video shows these very clearly:-
The largest of these is well-captured in the following still from the video:-
These are fairly typical seismically-induced, shallow, disrupted rock and debris slides, probably mainly consisting of weathered material sliding on the interface with more intact bedrock. Whilst they will cause some disruption, it should not be difficult to reopen the road. Care will be needed in case of further landslides during aftershocks.
Again, these are shallow rock and debris slides. Note that there were people on the beach at the foot of the slopes. The location of these events is not clear.
There is a paywalled eyewitness account of the events posted by the Illawara Mercury, which is quite interesting. It provides an account from a tourist, Anita Struthers, which describes landslides on and around Lelepa island:-
“Then I looked over behind me as I was getting out of the water, and the waves just started rolling in – a huge tide – and the trees were sideways and rocking.
“I looked at the mountains that were just in front of us and they were crashing down with landslides.
“It took us several seconds to actually understand what was happening, and then it was the whole boat was rocking, and behind us on Lelepa island we saw a big landslide come down right next to the village there.”
Lelepa Island is located on the northeast side of Efate.
There are extensive reports that six people were killed in a landslide triggered by the Port Vila Earthquake, but it is not clear as to the circumstances. There have been some reports that a bus was struck, so this could be the event in question, but I’m awaiting further information.
ABC News reports that there may be further people trapped in a landslide, but again the numbers are unclear.