Officials downplay volcano danger
Friday 12 Apr 2013 10:18 a.m.
A Civil Defence official says if Rangitoto erupted, it could be "something nice to look at, rather than a real danger".
Auckland Civil Defence controller Clive Manley's comments follow new claims that Rangitoto erupted a number of times over a 1000-year period, before going quiet around 550 years ago.
Associate Professor Phil Shane of the University of Auckland says the new research is at odds with prevailing views on Auckland's volcanic field.
"The old paradigm was that these volcanoes erupt suddenly in a new location each time, and only live for months to a year or two," says Dr Shane.
"This needs to be revisited in light of the new Rangitoto history of activity."
Mr Manley says the discovery of volcanic activity at Rangitoto prior to the two known – and most recent – eruptions could change how Civil Defence responds to a future event.
"Up until now, until this research came out, we said that volcanoes could erupt anywhere – so you could say the safest place was on an existing volcano, because they could come up anywhere," he said on Firstline this morning.
"But what this has shown is that Rangitoto was different – it did have multiple eruptions, so Rangitoto appears to be the anomaly in the volcanic field in Auckland."
- VIDEO: Clive Manley on Firstline
Where an eruption takes place would have a large impact on how Civil Defence would react.
"About a third of [Auckland's volcanic field] is underwater, and the type of experience we'll have from a volcano will depend where it is.
"In some ways you could say Rangitoto is one of the safest places to have it, because it's not around a populated area, you've got water around it, so it could be – not a tourist attraction – but it literally could be something nice to look at, rather than a real danger. Whereas if it was in Mt Eden or somewhere, it would be a different thing."
Mr Manley reiterates however the discoveries don't change the risk Auckland faces.
"We're just as safe as we were before the research as we are now, but we understand a little bit more how the field might act.
"We also have a very good detection [system] in Auckland. We've got some deep bores under Auckland, and when a volcano starts coming up through the hard mantle, it sort of pushes its way through and makes little micro-earthquakes, we can detect those. We're told by the scientists we're going to get some warning before it comes up.
"Our planning is based on that we will be able to alert Aucklanders that a volcano is occurring, and we believe we will be able to safely evacuate people away from that area."
- READ MORE: Rangitoto more active than thought - study