NZ Herald
  • Home
  • Latest news
  • Herald NOW
  • Video
  • New Zealand
  • Sport
  • World
  • Business
  • Entertainment
  • Podcasts
  • Quizzes
  • Opinion
  • Lifestyle
  • Travel
  • Viva
  • Weather

Subscriptions

  • Herald Premium
  • Viva Premium
  • The Listener
  • BusinessDesk

Sections

  • Latest news
  • New Zealand
    • All New Zealand
    • Crime
    • Politics
    • Education
    • Open Justice
    • Scam Update
  • Herald NOW
  • On The Up
  • World
    • All World
    • Australia
    • Asia
    • UK
    • United States
    • Middle East
    • Europe
    • Pacific
  • Business
    • All Business
    • MarketsSharesCurrencyCommoditiesStock TakesCrypto
    • Markets with Madison
    • Media Insider
    • Business analysis
    • Personal financeKiwiSaverInterest ratesTaxInvestment
    • EconomyInflationGDPOfficial cash rateEmployment
    • Small business
    • Business reportsMood of the BoardroomProject AucklandSustainable business and financeCapital markets reportAgribusiness reportInfrastructure reportDynamic business
    • Deloitte Top 200 Awards
    • CompaniesAged CareAgribusinessAirlinesBanking and financeConstructionEnergyFreight and logisticsHealthcareManufacturingMedia and MarketingRetailTelecommunicationsTourism
  • Opinion
    • All Opinion
    • Analysis
    • Editorials
    • Business analysis
    • Premium opinion
    • Letters to the editor
  • Politics
  • Sport
    • All Sport
    • OlympicsParalympics
    • RugbySuper RugbyNPCAll BlacksBlack FernsRugby sevensSchool rugby
    • CricketBlack CapsWhite Ferns
    • Racing
    • NetballSilver Ferns
    • LeagueWarriorsNRL
    • FootballWellington PhoenixAuckland FCAll WhitesFootball FernsEnglish Premier League
    • GolfNZ Open
    • MotorsportFormula 1
    • Boxing
    • UFC
    • BasketballNBABreakersTall BlacksTall Ferns
    • Tennis
    • Cycling
    • Athletics
    • SailingAmerica's CupSailGP
    • Rowing
  • Lifestyle
    • All Lifestyle
    • Viva - Food, fashion & beauty
    • Society Insider
    • Royals
    • Sex & relationships
    • Food & drinkRecipesRecipe collectionsRestaurant reviewsRestaurant bookings
    • Health & wellbeing
    • Fashion & beauty
    • Pets & animals
    • The Selection - Shop the trendsShop fashionShop beautyShop entertainmentShop giftsShop home & living
    • Milford's Investing Place
  • Entertainment
    • All Entertainment
    • TV
    • MoviesMovie reviews
    • MusicMusic reviews
    • BooksBook reviews
    • Culture
    • ReviewsBook reviewsMovie reviewsMusic reviewsRestaurant reviews
  • Travel
    • All Travel
    • News
    • New ZealandNorthlandAucklandWellingtonCanterburyOtago / QueenstownNelson-TasmanBest NZ beaches
    • International travelAustraliaPacific IslandsEuropeUKUSAAfricaAsia
    • Rail holidays
    • Cruise holidays
    • Ski holidays
    • Luxury travel
    • Adventure travel
  • Kāhu Māori news
  • Environment
    • All Environment
    • Our Green Future
  • Talanoa Pacific news
  • Property
    • All Property
    • Property Insider
    • Interest rates tracker
    • Residential property listings
    • Commercial property listings
  • Health
  • Technology
    • All Technology
    • AI
    • Social media
  • Rural
    • All Rural
    • Dairy farming
    • Sheep & beef farming
    • Horticulture
    • Animal health
    • Rural business
    • Rural life
    • Rural technology
    • Opinion
    • Audio & podcasts
  • Weather forecasts
    • All Weather forecasts
    • Kaitaia
    • Whangārei
    • Dargaville
    • Auckland
    • Thames
    • Tauranga
    • Hamilton
    • Whakatāne
    • Rotorua
    • Tokoroa
    • Te Kuiti
    • Taumaranui
    • Taupō
    • Gisborne
    • New Plymouth
    • Napier
    • Hastings
    • Dannevirke
    • Whanganui
    • Palmerston North
    • Levin
    • Paraparaumu
    • Masterton
    • Wellington
    • Motueka
    • Nelson
    • Blenheim
    • Westport
    • Reefton
    • Kaikōura
    • Greymouth
    • Hokitika
    • Christchurch
    • Ashburton
    • Timaru
    • Wānaka
    • Oamaru
    • Queenstown
    • Dunedin
    • Gore
    • Invercargill
  • Meet the journalists
  • Promotions & competitions
  • OneRoof property listings
  • Driven car news

Puzzles & Quizzes

  • Puzzles
    • All Puzzles
    • Sudoku
    • Code Cracker
    • Crosswords
    • Cryptic crossword
    • Wordsearch
  • Quizzes
    • All Quizzes
    • Morning quiz
    • Afternoon quiz
    • Sports quiz

Regions

  • Northland
    • All Northland
    • Far North
    • Kaitaia
    • Kerikeri
    • Kaikohe
    • Bay of Islands
    • Whangarei
    • Dargaville
    • Kaipara
    • Mangawhai
  • Auckland
  • Waikato
    • All Waikato
    • Hamilton
    • Coromandel & Hauraki
    • Matamata & Piako
    • Cambridge
    • Te Awamutu
    • Tokoroa & South Waikato
    • Taupō & Tūrangi
  • Bay of Plenty
    • All Bay of Plenty
    • Katikati
    • Tauranga
    • Mount Maunganui
    • Pāpāmoa
    • Te Puke
    • Whakatāne
  • Rotorua
  • Hawke's Bay
    • All Hawke's Bay
    • Napier
    • Hastings
    • Havelock North
    • Central Hawke's Bay
    • Wairoa
  • Taranaki
    • All Taranaki
    • Stratford
    • New Plymouth
    • Hāwera
  • Manawatū - Whanganui
    • All Manawatū - Whanganui
    • Whanganui
    • Palmerston North
    • Manawatū
    • Tararua
    • Horowhenua
  • Wellington
    • All Wellington
    • Kapiti
    • Wairarapa
    • Upper Hutt
    • Lower Hutt
  • Nelson & Tasman
    • All Nelson & Tasman
    • Motueka
    • Nelson
    • Tasman
  • Marlborough
  • West Coast
  • Canterbury
    • All Canterbury
    • Kaikōura
    • Christchurch
    • Ashburton
    • Timaru
  • Otago
    • All Otago
    • Oamaru
    • Dunedin
    • Balclutha
    • Alexandra
    • Queenstown
    • Wanaka
  • Southland
    • All Southland
    • Invercargill
    • Gore
    • Stewart Island
  • Gisborne

Media

  • Video
    • All Video
    • NZ news video
    • Herald NOW
    • Business news video
    • Politics news video
    • Sport video
    • World news video
    • Lifestyle video
    • Entertainment video
    • Travel video
    • Markets with Madison
    • Kea Kids news
  • Podcasts
    • All Podcasts
    • The Front Page
    • On the Tiles
    • Ask me Anything
    • The Little Things
  • Cartoons
  • Photo galleries
  • Today's Paper - E-editions
  • Photo sales
  • Classifieds

NZME Network

  • Advertise with NZME
  • OneRoof
  • Driven Car Guide
  • BusinessDesk
  • Newstalk ZB
  • Sunlive
  • ZM
  • The Hits
  • Coast
  • Radio Hauraki
  • The Alternative Commentary Collective
  • Gold
  • Flava
  • iHeart Radio
  • Hokonui
  • Radio Wanaka
  • iHeartCountry New Zealand
  • Restaurant Hub
  • NZME Events

SubscribeSign In
Advertisement
Advertise with NZME.
Home / New Zealand

Auckland low-risk for quakes, but no way to know for sure

By Geoff Cumming
NZ Herald·
13 May, 2011 05:30 PM4 mins to read

Subscribe to listen

Access to Herald Premium articles require a Premium subscription. Subscribe now to listen.
Already a subscriber?  Sign in here

Listening to articles is free for open-access content—explore other articles or learn more about text-to-speech.
‌
Save

    Share this article

There's no way to know for sure about what's rumbling under Auckland's surface. Photo / Richard Robinson
There's no way to know for sure about what's rumbling under Auckland's surface. Photo / Richard Robinson

There's no way to know for sure about what's rumbling under Auckland's surface. Photo / Richard Robinson

Auckland is deemed a low earthquake hazard in calculations by GNS Science (the Institute of Geological and Nuclear Sciences) - who provide the earthquake science on which building rules are founded. But, says Mark Stirling, GNS lead scientist in seismic hazard modelling, there is always the possibility.

The city is a long way from the nearest plate boundary, which runs north from Wellington through to Taupo then towards East Cape, and where heightened seismic activity could be expected. The location dictates an "intra-plate regime rather than an edge of plate regime", says Stirling, responsible for GNS's hazard modelling programme.

The nearest known active fault, Wairoa North, runs from the Hunua Ranges through Clevedon, about 30 km from the CBD. Its recurrence interval is assessed at one in 20,000 years. The only other known fault, Kerepehi East, runs from the Hauraki Plains into the Firth of Thames. Its recurrence interval is "in the thousands rather than tens of thousands of years" but its distance from Auckland makes it not quite so serious, says Stirling.

"In terms of probability, Auckland is the lowest risk of all our main centres in terms of the likelihood of strong shaking."

Then come the riders. Hazard modelling can forecast recurrence timeframes for earthquakes of various magnitudes but can't say when a very rare event, a big one, is going to happen.

The scientists rely a lot on surface expression - evidence of a fault in the landscape and to a lesser extent on seismicity. "Something has to have happened often enough for it to be expressed in the landscape. You can have active features that have no expression."

The two Canterbury quakes have highlighted the uncertainties. The recurrence interval for a quake on the Canterbury Plains was one every 16,000 years "but the model is incapable of saying it's going to happen in 2010 or 2011".

"There was no way of telling the Greendale fault (which ruptured near Darfield) was there beforehand unless some funding agency wanted us to do detailed geophysical analysis.

"Canterbury tells us to worry about unknown faults close to the city."

Auckland experiences low magnitude shocks often enough to show the region is not seismically dead. "There's always a possibility we could end up with a larger quake."

The most recent reasonable shudder, a 4.5 magnitude quake off Orewa in 2007, woke children sleeping in Mt Roskill.

Auckland has only two known faults but there may be more, as the previously unknown Canterbury faults suggest. "We haven't that much information on Wairoa North beause it is not moving very fast."

Faults considered dead may not be dead in future. And the relationship between seismicity and faulting is not one-to-one; seismicity doesn't always occur directly on faults. "The presence of seismicity tells you an area is tectonically active, just as volcanism indicates that there is crustal activity going on."

The area's low seismicity means it is less well researched than others. Stirling says there could be a case for further research, "based on Canterbury's experience and knowing any faults in the Auckland area are going to have very long recurrence intervals and may not have topographic expression."

"Certainly the distance from the plate boundary makes the probabilities of large shaking quite low.

"But tomorrow there could be a one in 20,000 year earthquake."

Auckland's new buildings - built to modern ductile (flexible) engineering standards - are designed to withstand shaking from a moderate (6.5 magnitude) quake with maximum ground acceleration (G-force) of 1.3g, reflecting its distance from the plate boundary and known faults. In Christchurch, the tolerance level is 2.2g and in Wellington 4.5g. But the ground acceleration on February 24 far exceeded the model.

Is there a case for higher earthquake tolerance levels for older buildings - currently 33 per cent of the new building standard - in light of Christchurch?

"You would need to have convincing evidence of the seismic hazard in the area relevant to buildings."

Stirling says a recent review has lowered the seismic hazard for the Auckland region "because of the virtual absence of faults."

Discover more

New Zealand

Quake risk-list sends shock through the suburbs

13 May 05:30 PM
New Zealand

Retrofitting can be a low-cost option to strengthen at-risk older buildings

13 May 05:30 PM
New Zealand

Cities look to Christchurch for earthquake lessons

13 May 05:30 PM
Opinion

Tony Watkins: Why Auckland needs a red zone

26 Jul 09:30 PM
Advertisement
Advertise with NZME.
Advertisement
Advertise with NZME.
Save

    Share this article

Latest from New Zealand

New Zealand

Lotto Powerball jackpots to $10m, two winners split $1m

05 Jul 09:16 AM
New Zealand

Watch: Jet boat joy rides through swollen stream as severe weather batters parts of NZ

05 Jul 08:41 AM
Auckland

Person seriously injured falling from vehicle in Pokeno crash

05 Jul 08:16 AM

There’s more to Hawai‘i than beaches and buffets – here’s how to see it differently

sponsored
Advertisement
Advertise with NZME.
Recommended for you
All Blacks hold on, end France losing streak to open 2025
All Blacks

All Blacks hold on, end France losing streak to open 2025

05 Jul 09:19 AM
Lotto Powerball jackpots to $10m, two winners split $1m
New Zealand

Lotto Powerball jackpots to $10m, two winners split $1m

05 Jul 09:16 AM
Watch: Jet boat joy rides through swollen stream as severe weather batters parts of NZ
New Zealand

Watch: Jet boat joy rides through swollen stream as severe weather batters parts of NZ

05 Jul 08:41 AM
Person seriously injured falling from vehicle in Pokeno crash
Auckland

Person seriously injured falling from vehicle in Pokeno crash

05 Jul 08:16 AM
Recap: All Black beat France to begin 2025 campaign
All Blacks

Recap: All Black beat France to begin 2025 campaign

05 Jul 07:57 AM

Latest from New Zealand

Lotto Powerball jackpots to $10m, two winners split $1m

Lotto Powerball jackpots to $10m, two winners split $1m

05 Jul 09:16 AM

The winning tickets were sold in Auckland and on MyLotto to a Waikato player.

Watch: Jet boat joy rides through swollen stream as severe weather batters parts of NZ

Watch: Jet boat joy rides through swollen stream as severe weather batters parts of NZ

05 Jul 08:41 AM
Person seriously injured falling from vehicle in Pokeno crash

Person seriously injured falling from vehicle in Pokeno crash

05 Jul 08:16 AM
'Very sad and tragic': Baby found critically hurt at house dies, homicide probe launched

'Very sad and tragic': Baby found critically hurt at house dies, homicide probe launched

05 Jul 06:33 AM
From early mornings to easy living
sponsored

From early mornings to easy living

NZ Herald
  • About NZ Herald
  • Meet the journalists
  • Newsletters
  • Classifieds
  • Help & support
  • Contact us
  • House rules
  • Privacy Policy
  • Terms of use
  • Competition terms & conditions
  • Our use of AI
Subscriber Services
  • NZ Herald e-editions
  • Daily puzzles & quizzes
  • Manage your digital subscription
  • Manage your print subscription
  • Subscribe to the NZ Herald newspaper
  • Subscribe to Herald Premium
  • Gift a subscription
  • Subscriber FAQs
  • Subscription terms & conditions
  • Promotions and subscriber benefits
NZME Network
  • The New Zealand Herald
  • The Northland Age
  • The Northern Advocate
  • Waikato Herald
  • Bay of Plenty Times
  • Rotorua Daily Post
  • Hawke's Bay Today
  • Whanganui Chronicle
  • Viva
  • NZ Listener
  • Newstalk ZB
  • BusinessDesk
  • OneRoof
  • Driven Car Guide
  • iHeart Radio
  • Restaurant Hub
NZME
  • About NZME
  • NZME careers
  • Advertise with NZME
  • Digital self-service advertising
  • Book your classified ad
  • Photo sales
  • NZME Events
  • © Copyright 2025 NZME Publishing Limited
TOP
search by queryly Advanced Search