Vanuatu: Strong earthquake of magnitude 7.3
Strong earthquake near Port Vila causes severe damage to buildings
The epicentre of the strong earthquake on 17 December 2024 at 01:47 UTC (12:47 local time) was located about 30 km west off the coast of Port Vila, capital of the Pacific state of Vanuatu. According to the USGS, the earthquake had a magnitude of 7.3 and, with a focal depth of around 55 kilometres, caused severe damage to buildings in the capital. Several fatalities have been reported so far. The earthquake also generated a tsunami with a height of 30 cm.
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Location of the epicentre (Source: USGS)
The capital Port Vila was particularly affected, where many buildings were severely damaged or collapsed, including a building housing the US embassy. The access road to the international harbour was also buried by heavy landslides. A large part of Vanuatu's communications network was destroyed, although the actual impact has yet to be assessed.
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Unfiltered seismogram of the Vanuatu earthquake of 17 December 2024, recorded at twelve selected stations of the Austrian Seismological Service. It shows a 23-minute section. The fastest earthquake wave (compression wave-P) took just under 20 minutes to reach Austria. © GeoSphere Austria.
There have already been several aftershocks with magnitudes of up to 5, and further aftershocks can be expected in the coming weeks and months.
The earthquake occurred in the Vanuatu subduction zone. This is a section of a large-scale tectonic fault where the Pacific and Australian plates collide. This plate boundary is one of the most seismically active areas on earth. Along the 3000 km long plate boundary, the two tectonic plates move towards each other at a speed of 90 mm/year in the north and 60 mm/year in the south. In the last 100 years, a total of 24 earthquakes with a magnitude of 7 or more have occurred within a radius of 250 kilometres from Port Vila. The strongest event measured to date, in December 1950, had a magnitude of 7.9 (USGS).
Earthquakes that occur at great distances are also relevant for European institutions. As part of the EU multi-hazard project ARISTOTLE, the Earthquake Service and the Meteorological Service, together with other institutions from over ten countries, advise the Emergency Response Coordination Centre in Brussels. The ARISTOTLE project pursues a holistic and interdisciplinary approach to early warnings and assesses the impact of disasters (earthquakes, volcanic eruptions, tsunamis, floods and extreme weather), which may require the mobilisation of international relief forces.
Seismological Service of Austria - GeoSphere Austria Hohe Warte 38, A-1190 Vienna Tel. +43 1 36026 2508 E-mail: seismo@zamg.ac.at
Translated with DeepL.com (free version)