We'll soon be able to map quake impacts - as they happen

New Zealand will soon have a "four-dimensional" picture of earthquakes and tsunamis as they happen - enabling Kiwis to prepare for their impacts in near real-time. Photo / NZTA

New Zealand will soon have a "four-dimensional" picture of earthquakes and tsunamis as they happen - enabling Kiwis to prepare for their impacts in near real-time.

A new GNS Science-led project will equip the country with one of the most sophisticated hazard-modelling systems in the world, with the potential to save lives and damage here and across the southwest Pacific.

It aimed to harness the combined power of our quake and tsunami monitoring equipment, with new advanced analytical tech to create faster - and more specific - data within minutes of a big quake.

It also meant changing how we initially assessed an unfolding disaster.

"Currently in the immediate aftermath of an earthquake, we define a quake as a point source in the Earth, giving it a location and depth," explained the project's leader, Dr Bill Fry.

But, by treating a quake as a dot on a map, the tsunami early warning and strong ground shaking estimates failed to consider its true extent.

Fry pointed to 2016's magnitude 7.8 Kaikoura Earthquake, which erupted from an epicentre near Culverden in North Canterbury, but caused severe impacts all the way north to Wellington.

"In the Kaikoura case, it involved the breaking of more than 20 faults that extended more than 160km to the northeast of Culverden," he said.

"So in the moments following a large earthquake, we need to consider the entire geographical extent of an earthquake rather than just the epicentre."

Fry said the five-year project will effectively build a four-dimensional picture of earthquakes – combining space and time – so first responders and decision-makers could receive instant reports of impacts.

Its main focus would be on the two types of quakes that pose the most severe hazard to New Zealand - large local quakes and those in the southwest Pacific big enough to kick off tsunamis.

Developing realistic new shaking assessments that highlighted the severity of potential damage would quickly help guide recovery efforts.

A new network of seismic instruments would also be established in Northland - ideally located to pick up signals from quakes and volcanoes in the Pacific.

And a recently installed array of Dart buoys to the north and east of the country would help scientists accurately forecast tsunami arrival times and sizes.

"The new array will allow us to test a range of previously unattainable early warning tools," Fry said.

"The best performing of these tools will find their way into response, in New Zealand and across the southwest Pacific."

By providing more rapid and accurate understanding of natural hazards as they occurred, Fry said, society could brace for the impacts, and be more able to safely pick up the pieces.

"In the minutes after a big earthquake, some damage will already be done and some, like further shaking or tsunamis, may still be on the way," he said.

"Our programme addresses these aspects with the aim of making New Zealand and the greater Southwest Pacific a safer and more prosperous region."

The project has been awarded $13.2 million over five years from the Ministry for Business, Innovation and Employment's Endeavour Fund.