Earthquakes in New Zealand

Earthquakes in New Zealand occur as the country forms part of the Pacific Ring of Fire, which is geologically active. About 20,000 earthquakes, most of them minor, are recorded each year.[1] About 200 of these are strong enough to be felt.[2] As a result, New Zealand has very stringent building regulations.

Contents

Distribution

Most earthquakes in New Zealand occur along the main ranges running from Fiordland in the southwest to East Cape in the northeast. This axis follows the boundary between the Indo-Australian and Pacific plates. Large earthquakes are less common along the central Alpine Fault, where the plates are not subducting and the forces are accommodated in different ways.

The largest city within this high risk zone is the nation's capital, Wellington, followed by Hastings then Napier. All these cities have experienced severe earthquakes since European settlement.

Societal effects

New Zealand is sometimes nicknamed the Shaky Isles.[3] Quite early on, European settlers were faced with the reality of earthquakes in their new home. On 26 May 1840, the new settlement of Port Nicholson was struck by the first of a number of earthquakes and tremors.[4]

Public education

The New Zealand Earthquake Commission (EQC) provides public education to much of the country. As outlined in its statement of intent it hopes to provide "public education about seismic hazards and methods of reducing or preventing seismic disaster damage." The EQC sponsors exhibitions on seismic hazards in the Te Papa Museum of New Zealand, and is responsible for social marketing campaigns.[5] An extensive advertising campaign by the EQC across New Zealand's main television networks ran from June 2005 to June 2006. The adverts outlined the risks earthquakes pose to New Zealand and measures households can take to "Quake Safe their house." The slogan used throughout EQC Quake Safe campaigns is "Fix. Fasten. Forget."[6] Additionally in October 2006 many households received free "EQ-IQ" fridge magnets from the EQC.[7]

Building regulations

Early settlers learned fairly quickly the importance of using appropriate building methods in an earthquake-prone country. The 1848 earthquake, centred in Marlborough, caused great damage to the brick and masonry buildings in Wellington, and the city was rebuilt mainly in wood; consequently it suffered comparatively little damage in the 8.2 magnitude earthquake of 1855, which lifted the land 2–3m.[8]

Major earthquakes

Date Location Magnitude Fatalities Further information
c.1100 Alpine Fault 8 0 [9]
c.1450 Wellington Region 8 unknown Haowhenua[10]
c.1610-20 Alpine Fault 8 unknown [9][11]
1717 Alpine Fault 8 unknown [9][11]
1826 Fiordland 7.5 unknown [11]
08 Jul 1843 Wanganui 7.0 2 1843 Wanganui earthquake
16 Oct 1848 Marlborough 7.5 3 1848 Marlborough earthquake
23 Jan 1855 Wairarapa 8.2 9 1855 Wairarapa earthquake[12][13][14][15]
23 Feb 1863 Hawke's Bay 7.5 Unknown
19 Oct 1868 Cape Farewell 7.5 Unknown
05 Jun 1869 Christchurch 5.2 0[16] 1869 Christchurch earthquake
01 Sep 1888 North Canterbury 7.1 0 1888 North Canterbury earthquake
12 Feb 1893 Nelson 6.9 Unknown
16 Nov 1901 Cheviot 6.9 1 1901 Cheviot earthquake
25 Dec 1922 Motunau 6.4 Unknown
09 Mar 1929 Arthur's Pass 7.1 Unknown 1929 Arthur's Pass earthquake
17 Jun 1929 Murchison 7.8 17 1929 Murchison earthquake
03 Feb 1931 Hawke's Bay 7.8 256 1931 Hawke's Bay earthquake
13 Feb 1931 Hawke's Bay 7.3 - Aftershock to 3 Feb 1931
05 Mar 1934 Pahiatua 7.6 2 1934 Pahiatua earthquake
24 Jun 1942 Wairarapa 7.2 0 June 1942 Wairarapa earthquake
02 Aug 1942 Wairarapa 7.0 1 August 1942 Wairarapa earthquake
26 Jun 1946 Lake Coleridge 6.2 0
24 May 1968 Inangahua Junction 7.1 2
15 Jan 1976 Kermadec Islands 8.2 0
21 Oct 1986 Kermadec Islands 8.3 0
07 Mar 1987 Edgecumbe 6.5 0 1987 Edgecumbe earthquake
04 Jun 1988 Te Anau, Fiordland 6.7 0
24 May 1989 Puysegur Trench 8.2 0
13 May 1990 Weber 6.4[17] 0
10 Aug 1993 Secretary Island 6.8 0
18 Jun 1994 Arthur's Pass 6.7[18] 0
06 Feb 1995 East Cape 7.0 0
22 Aug 2003 Fiordland 7.2 0
24 Dec 2004 Puysegur Trench 8.1 0
15 Oct 2007 Arthur's Pass 6.8 0
18 Oct 2007 George Sound 6.7 0
20 Dec 2007 Gisborne 6.8 0 2007 Gisborne earthquake
30 Sep 2008 Kermadec Islands 7.0 0
15 Jul 2009 Fiordland 7.8 0 2009 Fiordland earthquake
04 Sep 2010 Darfield, Canterbury 7.1[19] 0 2010 Canterbury earthquake
29 Sep 2010 White Island 6.4 0
22 Feb 2011 Christchurch 6.3 181[20] February 2011 Christchurch earthquake
13 Jun 2011 Christchurch 6.4 1 June 2011 Christchurch earthquake
05 Jul 2011 Taupo 6.5 0
07 Jul 2011 Kermadec Islands 7.6 0
15 Sep 2011 NE of New Zealand 6.0 0
22 Oct 2011 Kermadec Islands 7.4 0
18 Nov 2011 NE of New Zealand 6.1 0
23 Dec 2011 Christchurch 5.8 0
23 Dec 2011 Christchurch 6.0 0

See also

References

  1. ^ Radio NZ news report on 2007 Gisborne earthquake
  2. ^ Earthquakes: The Short Story, Te Ara Encyclopedia of New Zealand
  3. ^ "New Zealand's land and environment"Ministry for the Environment
  4. ^ Dench, p 57
  5. ^ EQC Statement of Intent [1] EQC Statement of Intent
  6. ^ "EQC Annual Report 2006-2007"EQC Annual Report 2006-2007
  7. ^ "EQC Annual Report 2005-2006"EQC Annual Report 2005-2006
  8. ^ McSaveney, Eileen 'Earthquakes', Te Ara - the Encyclopedia of New Zealand, updated 21-Sep-2007
  9. ^ a b c "Alpine Fault". GNS Science. http://www.gns.cri.nz/Home/Learning/Science-Topics/Earthquakes/Major-Faults-in-New-Zealand/Alpine-Fault. Retrieved 29 November 2011. 
  10. ^ Maclean, Chris (3 March 2009). "Creation stories and landscape - Wellington region". Te Ara Encyclopedia of New Zealand. http://www.teara.govt.nz/en/wellington-region/2. Retrieved 29 November 2011. 
  11. ^ a b c Louise E. Cullen, Richard P. Duncan, Andrew Wells & Glenn H. Stewart (2003). "Floodplain and regional scale variation in earthquake effects on forests, Westland, New Zealand". Journal of the Royal Society of New Zealand 33 (4). doi:10.1080/03014223.2003.9517753. http://www.tandfonline.com/doi/pdf/10.1080/03014223.2003.9517753. Retrieved 29 November 2011. 
  12. ^ GeoNet. "M 8.2, Wairarapa, January 23 1855". http://www.geonet.org.nz/earthquake/historic-earthquakes/top-nz/quake-02.html. Retrieved 26 December 2011. 
  13. ^ McSaveney, M.J., Graham, I.J., Begg, J.G., Beu, A.G., Hull, A.G., Kyeong, K. & Zondervan, A. 2006. Late Holocene uplift of beach ridges at Turakirae Head, south Wellington coast, New Zealand. New Zealand Journal of Geology and Geophysics abstracts, 49, 337-358.
  14. ^ Rodgers, D.W.; Little T.A. (2006). "World's largest coseismic strike-slip offset: The 1855 rupture of the Wairarapa Fault, New Zealand, and implications for displacement/length scaling of continental earthquakes". Journal of Geophysical Research 111 (B12408). doi:10.1029/2005JB004065. http://www.agu.org/pubs/crossref/2006.../2005JB004065.shtml. 
  15. ^ McSaveney, Eileen (2 Mar 2009). "Story: Historic earthquakes Page 3 – The 1855 Wairarapa earthquake". Te Ara - the Encyclopedia of New Zealand. http://www.teara.govt.nz/en/historic-earthquakes/3. Retrieved 26 December 2011. 
  16. ^ "Our Shaky History". Environment Canterbury. http://ecan.govt.nz/advice/emergencies-and-hazard/earthquakes/Documents/shaky_history.swf. Retrieved 21 October 2011. 
  17. ^ "GeoNet - M6.4, Weber II, May 13, 1990". GeoNet. 13 May 1990. http://www.geonet.org.nz/earthquake/historic-earthquakes/more-nz/quake-09.html. Retrieved 5 September 2010. 
  18. ^ http://www.informaworld.com/smpp/content~db=all~content=a920225718 informaworld.com
  19. ^ "New Zealand earthquake report - Sep 4 2010 at 4:35 am (NZST)". GeoNet. 4 September 2010. http://www.geonet.org.nz/earthquake/quakes/3366146g.html. Retrieved 4 September 2010. 
  20. ^ "List of deceased - Christchurch earthquake". New Zealand Police. 3 May 2011. http://www.police.govt.nz/list-deceased. Retrieved 31 May 2011. 

Further reading

External links

Seismic faults of New Zealand
North Island
North Island Fault System
South Island
Marlborough Fault System
Canterbury Fault System
Other