Earthquakes in Vanuatu are frequent and are sometimes accompanied by tsunami, though these events are not often destructive. The archipelago, which was formerly known as New Hebrides, lies atop a complex and active plate boundary in the southwestern Pacific Ocean.

Overall, the population in this region resides in structures that are highly vulnerable to earthquake shaking, though some resistant structures exist. Most buildings in Vanuatu are constructed with lumber.[1]

Tectonic setting

The primary tectonic feature of the 1,200 km (750 mi) island chain is the New Hebrides Trench, the convergent boundary of the Australian and Pacific Plates. Along the Wadati–Benioff zone, earthquake activity has been observed as shallow, intermediate, and deep-focus events at depths of up to 700 km (430 mi). Volcanic activity is also present along this north-northwest trending and northeast-dipping oceanic trench.[2]

While much of the island arc experiences intermediate-depth earthquakes along a Wadati–Benioff zone that dips steeply at 70°, the area adjacent to the d'Entrecasteaux Ridge does not. There is a corresponding gap in seismicity that occurs below 50 km (31 mi) where it intrudes into the subduction zone from the west. According to the NUVEL-1 global relative plate motion model, convergence is occurring at roughly 8 cm (3.1 in) per year. The uncertainty, which also affects the Tonga arc, is due to the influence of spreading at the North Fiji Basin. Of the 58 M7 or greater events that occurred between 1909 and 2001, few were studied.[3]

Earthquakes

Date Region Mag. MMI Deaths Injuries Comments Ref
2023-01-08 Espiritu Santo 7.0 Mw VII Major damage [4][5]
2018-12-16 Ambrym 5.5 Mw VI Several houses destroyed [6][7]
2018-08-21 Pentecost 6.5 Mw VII 1 Minor damage [8]
2010-12-25 Tafea 7.3 Mw V 4 Minor damage/tsunami [9][10]
2010-08-10 Shefa 7.3 Mw VII Buildings damaged/Power outages [11][12]
2009-10-07 Torba 7.4 Mw VIII
2009-10-07 Torba 7.8 Mw VII Tsunami
2009-10-07 Torba 7.7 Mw IX
2009-06-03 Efate 6.3 Mw VI 4 Landslides [13]
2009-05-29 Efate 5.7 Mw VI 10 Landslides / damage [14]
2007-08-01 Sanma 7.2 Mw VII 1 Many buildings damaged [15][16]
2002-11-28 Torba 5.9 Mw VII 3 Landslides / damage [17]
2002-01-03 Efate 7.2 Mw X Several Rockslides / damage [18]
1999-11-26 Ambrym 7.4 Mw VIII 5–10 40–100 Landslides / damage / five killed by tsunami
1999-08-22 Ambrym 6.6 Mw IX[19] Foreshock / landslides [20]
1997-04-21 Santa Cruz Islands 7.7 Mw VII Some damage / tsunami [21]
1992-10-11 Tanna 7.4 Mw VIII [22]
1990-07-27 Espiritu Santo 7.2 mb VII 2 Moderate damage [23]
1973-12-29 Espiritu Santo 7.2 Ms VIII Moderate damage
1973-12-29 Espiritu Santo 7.5 Ms VIII Moderate damage NGDC 1972
1971-10-27 Tutuba 6.8 Mw VI 1 Some Severe damage [24]
1965-08-11 Malakula 7.6 Mw IX Moderate damage / tsunami NGDC 1972
1910-11-10 Malakula 7.3 Mw VI Moderate damage / tsunami NGDC 1972
1909-07-08 Moderate damage / tsunami NGDC 1972
Note: The inclusion criteria for adding events are based on WikiProject Earthquakes' notability guideline that was developed for stand alone articles. The principles described also apply to lists. In summary, only damaging, injurious, or deadly events should be recorded.

See also

References

  1. ^ "PAGER". earthquake.usgs.gov.
  2. ^ Yeats, R. (2012), Active Faults of the World, Cambridge University Press, p. 478, ISBN 978-0521190855
  3. ^ Frolich, C. (2006). Deep Earthquakes. Cambridge University Press. pp. 399–401. ISBN 978-0805836523.
  4. ^ "M 7.0 - 23 km WNW of Port-Olry, Vanuatu". United States Geological Survey. 8 January 2023.
  5. ^ "Se registra terremoto de magnitud 7.0 en Vanuatu; no se reportaron víctimas" [7.0 magnitude earthquake recorded in Vanuatu; no casualties were reported]. El Mañana (in Spanish).
  6. ^ "M 5.5 - 82 km ESE of Lakatoro, Vanuatu". earthquake.usgs.gov. Retrieved 2018-12-27.
  7. ^ "Vanuatu eruption sparks series of quakes". Radio New Zealand. 2018-12-18. Retrieved 2018-12-27.
  8. ^ "M 6.5 - 78km E of Lakatoro, Vanuatu". earthquake.usgs.gov. Retrieved 2018-08-21.
  9. ^ "M 7.3 - 141 km W of Isangel, Vanuatu". earthquake.usgs.gov. 25 December 2010.
  10. ^ "Tsunami Event: Vanuatu". National Geophysical Data Center.
  11. ^ "M 7.3 - 33 km NW of Port-Vila, Vanuatu". earthquake.usgs.gov. Retrieved 2022-04-05.
  12. ^ "Earthquake panics Vanuatu residents". The Sydney Morning Herald. 2010-08-04. Retrieved 2022-04-05.
  13. ^ USGS. "M6.3 - Vanuatu". United States Geological Survey.
  14. ^ USGS. "M5.7 - Vanuatu". United States Geological Survey.
  15. ^ "M 7.2 - 56 km E of Luganville, Vanuatu". earthquake.usgs.gov. Retrieved 2022-03-02.
  16. ^ "Powerful earthquake damages Luganville on Vanuatu island of Santo". Radio New Zealand. 2007-08-02. Retrieved 2022-03-01. A police officer was injured during the 7.2 magnitude quake as he tried to leave police headquarters and many residents fled their homes when it struck at about 4am local time.
  17. ^ USGS. "M5.9 - Vanuatu". United States Geological Survey.
  18. ^ USGS. "M7.2 - Vanuatu". United States Geological Survey.
  19. ^ USGS (2 March 2023). "PAGER" (PDF). Retrieved 3 April 2023.
  20. ^ "M6.6 - Vanuatu". United States Geological Survey. Retrieved September 18, 2016.
  21. ^ USGS. "M7.7 - Santa Cruz Islands". United States Geological Survey.
  22. ^ "M 7.4 - 47 km NW of Isangel, Vanuatu". earthquake.usgs.gov.
  23. ^ USGS. "M7.2 - Vanuatu". United States Geological Survey.
  24. ^ USGS. "M6.8 - Vanuatu". United States Geological Survey.

Sources

Further reading

External links

List of earthquakes in Oceania
Categories