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Coordinates: 45°43′16″S 166°38′35″E / 45.721°S 166.643°E / -45.721; 166.643
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|aftershocks >100}}
|aftershocks >100}}


The '''2009 Fiordland earthquake''' was a magnitude 7.6 [[earthquake]]<ref name="USGS">{{cite web|url=http://earthquake.usgs.gov/eqcenter/eqinthenews/2009/us2009jcap/|title=Magnitude 7.6 - OFF WEST COAST OF THE SOUTH ISLAND, N.Z.|date=2009-07-15, 09:22:32 UTC |publisher=USGS|accessdate=2009-07-15}}</ref> that struck the [[South Island]] of [[New Zealand]] at 9:22&nbsp;pm ([[NZST]]) on 15 July 2009. The earthquake was centred in the remote region of [[Fiordland]], with the epicentre located {{convert|150|km|mi|abbr=on}} west-north-west of [[Invercargill]] near [[Dusky Sound]] in [[Fiordland National Park]], at a depth of {{convert|12|km|mi|abbr=on}}.<ref name="USGS"/><ref name="GeoNet">{{cite web|url=http://www.geonet.org.nz/earthquake/quakes/3124785g.html|title=New Zealand Earthquake Report - Jul 15 2009 at 9:22 pm (NZST)|date=2009-07-15, 09:22 UTC |publisher=GeoNet|accessdate=2009-07-16}}</ref> It is the largest New Zealand earthquake since the [[1931 Hawke's Bay earthquake]], which also had a magnitude of 7.6,<ref name="Geonet80years"/> and the largest in the world (to date) in 2009.<ref>{{cite news | url = http://www.stuff.co.nz/national/2607339/Weaker-more-frequent-Fiordland-aftershocks |title = "Weaker, more frequent Fiordland aftershocks" | work = Stuff.co.nz |author = NZPA | date = 19-07-2009}}</ref>
The '''2009 Fiordland earthquake''' was a magnitude 7.6 [[earthquake]]<ref name="USGS">{{cite web|url=http://earthquake.usgs.gov/eqcenter/eqinthenews/2009/us2009jcap/|title=Magnitude 7.6 - OFF WEST COAST OF THE SOUTH ISLAND, N.Z.|date=2009-07-15, 09:22:32 UTC |publisher=USGS|accessdate=2009-07-15}}</ref> that struck the [[South Island]] of [[New Zealand]] at 9:22&nbsp;pm ([[NZST]]) on 15 July 2009. The earthquake was centred in the remote region of [[Fiordland]], with the epicentre located {{convert|150|km|mi|abbr=on}} west-north-west of [[Invercargill]] near [[Dusky Sound]] in [[Fiordland National Park]], at a depth of {{convert|12|km|mi|abbr=on}}.<ref name="USGS"/><ref name="GeoNet">{{cite web|url=http://www.geonet.org.nz/earthquake/quakes/3124785g.html|title=New Zealand Earthquake Report - Jul 15 2009 at 9:22 pm (NZST)|date=2009-07-15, 09:22 UTC |publisher=GeoNet|accessdate=2009-07-16}}</ref> It is the largest New Zealand earthquake since the [[1931 Hawke's Bay earthquake]], which also had a magnitude of 7.6,<ref name="Geonet80years"/> and the largest in the world (to date) in 2009.<ref>{{cite news | url = http://www.stuff.co.nz/national/2607339/Weaker-more-frequent-Fiordland-aftershocks |title = "Weaker, more frequent Fiordland aftershocks" | work = Stuff.co.nz |author = NZPA | date = 19-07-2009|archiveurl=http://www.webcitation.org/5iXnnO6mL|archivedate=2009-07-25|deadurl=no|accessdate=2009-07-21}}</ref>


==Magnitude and earth movement==
==Magnitude and earth movement==
[[Image:2009_New_Zealand_earthquake.jpg|thumb]]
[[Image:2009_New_Zealand_earthquake.jpg|thumb]]
The main shock was a [[Earthquakes#Earthquake_fault_types|reverse fault (thrust)]], with the [[Indo-Australian Plate]] [[subduction|subducting]] beneath the [[Pacific Plate]].<ref name="Geonet80years"/> The earthquake lifted a large area of land around the epicenter approximately 1 metre.<ref name="Radio NZ">{{cite web|url=http://www.radionz.co.nz/news/stories/2009/07/18/1245bc1e13d2|title=Ground raised one metre by quake|date=2009-07-18|publisher=Radio New Zealand}}</ref>
The main shock was a [[Earthquakes#Earthquake_fault_types|reverse fault (thrust)]], with the [[Indo-Australian Plate]] [[subduction|subducting]] beneath the [[Pacific Plate]].<ref name="Geonet80years"/> The earthquake lifted a large area of land around the epicenter approximately 1 metre.<ref name="Radio NZ">{{cite web|url=http://www.radionz.co.nz/news/stories/2009/07/18/1245bc1e13d2|title=Ground raised one metre by quake|date=2009-07-18|publisher=Radio New Zealand|archiveurl=http://www.webcitation.org/5iXniK1vJ|archivedate=2009-07-25|deadurl=no|accessdate=2009-07-21}}</ref>


New Zealand's [[Institute of Geological and Nuclear Sciences]] (GNS Science) initially measured the earthquake at magnitude 6.6,<ref name="BBC Tsunami alert after NZ earthquake">{{cite news|url=http://news.bbc.co.uk/2/hi/asia-pacific/8151530.stm|title=Tsunami alert after NZ earthquake|date=15 July 2009|publisher=[[BBC News]]|accessdate=2009-07-15}}</ref> but later revised the magnitude to 7.8.<ref name=stuff>{{cite news |author=[[New Zealand Press Association|NZPA]], Fairfax |date=2009-07-15 |title=Fiordland quake measures 7.8 |url=http://www.stuff.co.nz/national/2597897/Fiordland-quake-measures-7-8 |publisher=[[stuff.co.nz]] |accessdate=2009-07-15}}</ref> A few hours later, the magnitude was downgraded to 7.6.<ref name="BestSyndication">{{cite news |first=Marlene |last=Donor |date=2009-07-15 |title=New Zealand 7.6 Magnitude Earthquake – Second Tremor at 6.1 Magnitude |url=http://www.bestsyndication.com/?q=20090715_new_zealand_earthquake_7.8_magnitude_6_aftershock_south_west_island.htm |publisher=Best Syndication |accessdate=2009-07-23}}</ref>
New Zealand's [[Institute of Geological and Nuclear Sciences]] (GNS Science) initially measured the earthquake at magnitude 6.6,<ref name="BBC Tsunami alert after NZ earthquake">{{cite news|url=http://news.bbc.co.uk/2/hi/asia-pacific/8151530.stm|title=Tsunami alert after NZ earthquake|date=15 July 2009|publisher=[[BBC News]]|accessdate=2009-07-15}}</ref> but later revised the magnitude to 7.8.<ref name=stuff>{{cite news |author=[[New Zealand Press Association|NZPA]], Fairfax |date=2009-07-15 |title=Fiordland quake measures 7.8 |url=http://www.stuff.co.nz/national/2597897/Fiordland-quake-measures-7-8 |publisher=[[stuff.co.nz]] |accessdate=2009-07-15}}</ref> A few hours later, the magnitude was downgraded to 7.6.<ref name="BestSyndication">{{cite news |first=Marlene |last=Donor |date=2009-07-15 |title=New Zealand 7.6 Magnitude Earthquake – Second Tremor at 6.1 Magnitude |url=http://www.bestsyndication.com/?q=20090715_new_zealand_earthquake_7.8_magnitude_6_aftershock_south_west_island.htm |publisher=Best Syndication |accessdate=2009-07-23}}</ref>
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The reported energy release was compared to "500 million tonnes of TNT,[and] 25,000 times more powerful than the atomic bomb dropped on Nagasaki in 1945".<ref name="NZHaftershocks"/>
The reported energy release was compared to "500 million tonnes of TNT,[and] 25,000 times more powerful than the atomic bomb dropped on Nagasaki in 1945".<ref name="NZHaftershocks"/>


The quake twisted New Zealand's [[South Island]], with Puysegur Point, on the Southwestern tip of the island, moving 30 cm closer to Australia (westward); [[Te Anau]] moved 10 cm, [[Bluff, New Zealand|Bluff]] 3 cm and [[Dunedin]] 10 cm. It is also believed to have caused an increased stress in the southern, offshore part of the [[Alpine Fault]].<ref>{{cite news | url=http://www.stuff.co.nz/environment/2661208/Our-Australian-cousins-just-got-closer|title="Our Australian cousins just got closer" |work= The Press | author= Paul Gormon | publisher = Fairfax Media | date = 22/07/2009 }}</ref>
The quake twisted New Zealand's [[South Island]], with Puysegur Point, on the Southwestern tip of the island, moving 30 cm closer to Australia (westward); [[Te Anau]] moved 10 cm, [[Bluff, New Zealand|Bluff]] 3 cm and [[Dunedin]] 10 cm. It is also believed to have caused an increased stress in the southern, offshore part of the [[Alpine Fault]].<ref>{{cite news | url=http://www.stuff.co.nz/environment/2661208/Our-Australian-cousins-just-got-closer|title="Our Australian cousins just got closer" |work= The Press | author= Paul Gormon | publisher = Fairfax Media | date = 22/07/2009 |archiveurl=http://www.webcitation.org/5iXnjD2Wi|archivedate=2009-07-25|deadurl=no|accessdate=2009-07-21}}</ref>


==Effects==
==Effects==
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[[File:NASA fiordland 2009 earthquake.png|thumb|left|250px|NASA map showing epicentre of earthquake and its aftershocks]]
[[File:NASA fiordland 2009 earthquake.png|thumb|left|250px|NASA map showing epicentre of earthquake and its aftershocks]]


[[Tsunami]] warnings were issued soon after the earthquake by authorities in New Zealand and [[Australia]], as well as the [[Pacific Tsunami Warning Center]] in [[Hawaii]].<ref name="Reuters New Zealand quake sparks tsunami warnings">{{cite news|url=http://www.reuters.com/article/worldNews/idUSTRE56E2P120090715|title=New Zealand quake sparks tsunami warnings|date=2009-07-15|publisher=[[Reuters]]|language=English|accessdate=2009-07-15}}</ref> Civil defence officials in [[Southland]] also issued a 'potential tsunami' warning, stating their concerns about widely varying measurements of the earthquake.<ref name="NZH Dye"/> Reacting to the Pacific warnings, about fifty residents and tourists on [[Lord Howe Island]] were evacuated, and in [[Sydney]] a theatre in [[Bondi Beach]] was evacuated, and residents told to keep away from the shore.<ref>{{cite news | url = http://tvnz.co.nz/national-news/fiordland-quake-causes-evacuation-in-sydney-2849163 | title = "Fiordland quake causes evacuation in Sydney" | work = Television New Zealand News | date = July 16, 2009}}</ref> In the event, waves were recorded along New Zealand's western coastline, with a meter at Jackson Bay, [[Haast, New Zealand|Haast]], measuring the wave at one metre, peak to trough.<ref name="Geonet80years">{{cite web | url = http://www.geonet.org.nz/news/article-jul-16-2009-fiordland-quake-biggest-for-80-years.html | publisher = Institute of Geological and Nuclear Sciences | work = GeoNet | title = "Fiordland quake biggest for 80 years" | date = 16 July 2009 }}</ref> (An amplitude of 17 cm)<ref>{{cite web | url =http://wcatwc.arh.noaa.gov/2009/07/15/764975/02/message764975-02.htm| title = "Tsunami Information Statement" | work = West Coast and Alaska Tsunami Warning Center | date = 07/15/2009 }}</ref> The tsunami warnings were subsequently cancelled or reduced.<ref name=stuff/>
[[Tsunami]] warnings were issued soon after the earthquake by authorities in New Zealand and [[Australia]], as well as the [[Pacific Tsunami Warning Center]] in [[Hawaii]].<ref name="Reuters New Zealand quake sparks tsunami warnings">{{cite news|url=http://www.reuters.com/article/worldNews/idUSTRE56E2P120090715|title=New Zealand quake sparks tsunami warnings|date=2009-07-15|publisher=[[Reuters]]|language=English|accessdate=2009-07-15}}</ref> Civil defence officials in [[Southland]] also issued a 'potential tsunami' warning, stating their concerns about widely varying measurements of the earthquake.<ref name="NZH Dye"/> Reacting to the Pacific warnings, about fifty residents and tourists on [[Lord Howe Island]] were evacuated, and in [[Sydney]] a theatre in [[Bondi Beach]] was evacuated, and residents told to keep away from the shore.<ref>{{cite news | url = http://tvnz.co.nz/national-news/fiordland-quake-causes-evacuation-in-sydney-2849163 | title = "Fiordland quake causes evacuation in Sydney" | work = Television New Zealand News | date = July 16, 2009|archiveurl=http://www.webcitation.org/5iXnpAitu|archivedate=2009-07-25|deadurl=no|accessdate=2009-07-21}}</ref> In the event, waves were recorded along New Zealand's western coastline, with a meter at Jackson Bay, [[Haast, New Zealand|Haast]], measuring the wave at one metre, peak to trough.<ref name="Geonet80years">{{cite web | url = http://www.geonet.org.nz/news/article-jul-16-2009-fiordland-quake-biggest-for-80-years.html | publisher = Institute of Geological and Nuclear Sciences | work = GeoNet | title = "Fiordland quake biggest for 80 years" | date = 16 July 2009 |archiveurl=http://www.webcitation.org/5iXnfCA0j|archivedate=2009-07-25|deadurl=no|accessdate=2009-07-21}}</ref> (An amplitude of 17 cm)<ref>{{cite web | url =http://wcatwc.arh.noaa.gov/2009/07/15/764975/02/message764975-02.htm| title = "Tsunami Information Statement" | work = West Coast and Alaska Tsunami Warning Center | date = 07/15/2009 |archiveurl=http://www.webcitation.org/5iXnoFzBk|archivedate=2009-07-25|deadurl=no|accessdate=2009-07-21}}</ref> The tsunami warnings were subsequently cancelled or reduced.<ref name=stuff/>


==Aftershocks==
==Aftershocks==
A large [[aftershock]] was reported at 9:41 pm,<ref name=stuff/> measuring between 5.8 ([[United States Geological Survey|US Geological Survey]]) and 6.1 ([[GNS Science]]) on the Richter scale, at a depth of {{convert|5|km|mi|abbr=on}}.<ref>{{cite news |author=[[Australian Associated Press|AAP]] |title=Tsunami warning for east coast of Australia |publisher=[[news.com.au]] |url=http://www.news.com.au/story/0,27574,25787792-421,00.html |date=2009-07-15 |accessdate=2009-07-15}}</ref> GNS Science reported that the aftershock was also felt in the lower North Island.<ref name=stuff/> Over 100 aftershocks were recorded as the area settled down.<ref>{{cite news| url =http://www.radionz.co.nz/news/stories/2009/07/19/1245bc2c294a|title ="Aftershocks in Fiordland seen as normal" | work = Radio New Zealand News | date = 19-07-2009}}</ref> Several were over magnitude 5.<ref name="NZHaftershocks">{{cite news |url=http://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=10585054|title="After-shocks continue in Southland"|work= New Zealand Herald | author = Yvonne Tahana | date =17=07=2009}}</ref>
A large [[aftershock]] was reported at 9:41 pm,<ref name=stuff/> measuring between 5.8 ([[United States Geological Survey|US Geological Survey]]) and 6.1 ([[GNS Science]]) on the Richter scale, at a depth of {{convert|5|km|mi|abbr=on}}.<ref>{{cite news |author=[[Australian Associated Press|AAP]] |title=Tsunami warning for east coast of Australia |publisher=[[news.com.au]] |url=http://www.news.com.au/story/0,27574,25787792-421,00.html |date=2009-07-15 |accessdate=2009-07-15}}</ref> GNS Science reported that the aftershock was also felt in the lower North Island.<ref name=stuff/> Over 100 aftershocks were recorded as the area settled down.<ref>{{cite news| url =http://www.radionz.co.nz/news/stories/2009/07/19/1245bc2c294a|title ="Aftershocks in Fiordland seen as normal" | work = Radio New Zealand News | date = 19-07-2009|archiveurl=http://www.webcitation.org/5iXnlgpbg|archivedate=2009-07-25|deadurl=no|accessdate=2009-07-21}}</ref> Several were over magnitude 5.<ref name="NZHaftershocks">{{cite news |url=http://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=10585054|title="After-shocks continue in Southland"|work= New Zealand Herald | author = Yvonne Tahana | date =17=07=2009|archiveurl=http://www.webcitation.org/5iXnmfGc6|archivedate=2009-07-25|deadurl=no|accessdate=2009-07-21}}</ref>


== See also ==
== See also ==

Revision as of 02:23, 27 July 2009

2009 Fiordland earthquake
UTC time??
Magnitude7.6 Mw
Depth12 kilometres (7 mi)
Epicenter45°43′16″S 166°38′35″E / 45.721°S 166.643°E / -45.721; 166.643
Areas affected New Zealand
 Australia
Tsunami17 cm (6.7 in)
Casualties0

The 2009 Fiordland earthquake was a magnitude 7.6 earthquake[1] that struck the South Island of New Zealand at 9:22 pm (NZST) on 15 July 2009. The earthquake was centred in the remote region of Fiordland, with the epicentre located 150 km (93 mi) west-north-west of Invercargill near Dusky Sound in Fiordland National Park, at a depth of 12 km (7.5 mi).[1][2] It is the largest New Zealand earthquake since the 1931 Hawke's Bay earthquake, which also had a magnitude of 7.6,[3] and the largest in the world (to date) in 2009.[4]

Magnitude and earth movement

The main shock was a reverse fault (thrust), with the Indo-Australian Plate subducting beneath the Pacific Plate.[3] The earthquake lifted a large area of land around the epicenter approximately 1 metre.[5]

New Zealand's Institute of Geological and Nuclear Sciences (GNS Science) initially measured the earthquake at magnitude 6.6,[6] but later revised the magnitude to 7.8.[7] A few hours later, the magnitude was downgraded to 7.6.[8]

The reported energy release was compared to "500 million tonnes of TNT,[and] 25,000 times more powerful than the atomic bomb dropped on Nagasaki in 1945".[9]

The quake twisted New Zealand's South Island, with Puysegur Point, on the Southwestern tip of the island, moving 30 cm closer to Australia (westward); Te Anau moved 10 cm, Bluff 3 cm and Dunedin 10 cm. It is also believed to have caused an increased stress in the southern, offshore part of the Alpine Fault.[10]

Effects

The earthquake was felt throughout the South Island, and in the lower North Island as far as New Plymouth. No injuries or fatalities were reported, and it caused only minor damage.[7] Power outages were experienced in several parts of the South Island.[11][12] Over 200 claims for damage have been listed with the Earthquake Commission, New Zealand's agency for earthquake compensation, with more expected.[9]

Landslides in the Fiordland National Park near Dusky Sound cleared large tracts of forest.[9]

Tsunami

NASA map showing epicentre of earthquake and its aftershocks

Tsunami warnings were issued soon after the earthquake by authorities in New Zealand and Australia, as well as the Pacific Tsunami Warning Center in Hawaii.[13] Civil defence officials in Southland also issued a 'potential tsunami' warning, stating their concerns about widely varying measurements of the earthquake.[11] Reacting to the Pacific warnings, about fifty residents and tourists on Lord Howe Island were evacuated, and in Sydney a theatre in Bondi Beach was evacuated, and residents told to keep away from the shore.[14] In the event, waves were recorded along New Zealand's western coastline, with a meter at Jackson Bay, Haast, measuring the wave at one metre, peak to trough.[3] (An amplitude of 17 cm)[15] The tsunami warnings were subsequently cancelled or reduced.[7]

Aftershocks

A large aftershock was reported at 9:41 pm,[7] measuring between 5.8 (US Geological Survey) and 6.1 (GNS Science) on the Richter scale, at a depth of 5 km (3.1 mi).[16] GNS Science reported that the aftershock was also felt in the lower North Island.[7] Over 100 aftershocks were recorded as the area settled down.[17] Several were over magnitude 5.[9]

See also

References

  1. ^ a b "Magnitude 7.6 - OFF WEST COAST OF THE SOUTH ISLAND, N.Z." USGS. 2009-07-15, 09:22:32 UTC. Retrieved 2009-07-15. {{cite web}}: Check date values in: |date= (help)
  2. ^ "New Zealand Earthquake Report - Jul 15 2009 at 9:22 pm (NZST)". GeoNet. 2009-07-15, 09:22 UTC. Retrieved 2009-07-16. {{cite web}}: Check date values in: |date= (help)
  3. ^ a b c ""Fiordland quake biggest for 80 years"". GeoNet. Institute of Geological and Nuclear Sciences. 16 July 2009. Archived from the original on 2009-07-25. Retrieved 2009-07-21. {{cite web}}: Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
  4. ^ NZPA (19-07-2009). ""Weaker, more frequent Fiordland aftershocks"". Stuff.co.nz. Archived from the original on 2009-07-25. Retrieved 2009-07-21. {{cite news}}: Check date values in: |date= (help); Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
  5. ^ "Ground raised one metre by quake". Radio New Zealand. 2009-07-18. Archived from the original on 2009-07-25. Retrieved 2009-07-21. {{cite web}}: Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
  6. ^ "Tsunami alert after NZ earthquake". BBC News. 15 July 2009. Retrieved 2009-07-15.
  7. ^ a b c d e NZPA, Fairfax (2009-07-15). "Fiordland quake measures 7.8". stuff.co.nz. Retrieved 2009-07-15.
  8. ^ Donor, Marlene (2009-07-15). "New Zealand 7.6 Magnitude Earthquake – Second Tremor at 6.1 Magnitude". Best Syndication. Retrieved 2009-07-23.
  9. ^ a b c d Yvonne Tahana (17=07=2009). ""After-shocks continue in Southland"". New Zealand Herald. Archived from the original on 2009-07-25. Retrieved 2009-07-21. {{cite news}}: Check date values in: |date= (help); Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
  10. ^ Paul Gormon (22/07/2009). ""Our Australian cousins just got closer"". The Press. Fairfax Media. Archived from the original on 2009-07-25. Retrieved 2009-07-21. {{cite news}}: Check date values in: |date= (help); Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
  11. ^ a b Dye, Stuart; NZPA (2009-07-15). "South Island quake prompts 'potential tsunami' warning". The New Zealand Herald. Retrieved 2009-07-15.
  12. ^ "Quake strikes off New Zealand's Southland". Xinhua. 2009-07-15. Retrieved 2009-07-15.
  13. ^ "New Zealand quake sparks tsunami warnings". Reuters. 2009-07-15. Retrieved 2009-07-15.
  14. ^ ""Fiordland quake causes evacuation in Sydney"". Television New Zealand News. July 16, 2009. Archived from the original on 2009-07-25. Retrieved 2009-07-21. {{cite news}}: Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
  15. ^ ""Tsunami Information Statement"". West Coast and Alaska Tsunami Warning Center. 07/15/2009. Archived from the original on 2009-07-25. Retrieved 2009-07-21. {{cite web}}: Check date values in: |date= (help); Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
  16. ^ AAP (2009-07-15). "Tsunami warning for east coast of Australia". news.com.au. Retrieved 2009-07-15.
  17. ^ ""Aftershocks in Fiordland seen as normal"". Radio New Zealand News. 19-07-2009. Archived from the original on 2009-07-25. Retrieved 2009-07-21. {{cite news}}: Check date values in: |date= (help); Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
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