Kiwi company Jenlogix operates a network of Palert units that can be triggered by the P-waves that earthquakes send out before the more destructive S-waves arrive. / Jenlogix Office
A network of quake-sensing devices has captured how yesterday's 6.2 shake was felt around the country.
Kiwi company Jenlogix operates a network of Palert units that can be triggered by the P-waves that earthquakes send out before the more destructive S-waves arrive.
For its users – which range from councils,universities and district health boards to ports and power companies – the data these devices instantly fire out could offer a brief but critical window to activate emergency shut-downs.
When 2016's Kaikoura Earthquake struck, one Wellington user received 19 seconds warning time before the shaking began.
The Jenlogix-designed system also quickly produced Shake Maps that illustrated how ground acceleration varied around the country.
In yesterday's case, the first Shake Map was created even before all of the Wellington units triggered, and showed the shaking coming through from the north.
Subsequent maps showed the quake rolling through and down to the South Island.
Jenlogix business development manager Keith Swasbrook noted that the system didn't need to know the energy produced by a quake, or even its epicentre, to operate.
"This means the system provide very timely information that companies can use in their emergency management processes, such as where should they send engineers first to check on faults."
Further, the system sent out SMS messages and email alerts to individuals or groups to let them know the ground acceleration of the units.
This map - constructed from triggered devices two minutes after the quake - shows the varying shaking force around Wellington. Image / Jenlogix
"Some of the units have been placed in schools near the rail line, where the school benefits from these messages as well as KiwiRail for the level of ground movement of the track."
The units all streamed data to a central server, but also had triggers than could activate local emergency systems – such as stopping a lift at the next floor and open the doors, or turning off a gas supply.
The data was also made available to others such as GeoNet and Rapid Alert system of KiwiRail.
The system was originally developed in Taiwan, which experienced similar seismic activity to New Zealand, to help their civil defence officials understand the impact of a quake.
One of the Palert units. Photo / Jenlogix
"The primary aim was to develop a device that was cost-effective," Swasbrook said.
"The early warning feature was developed in the university. This early warning has been rolled out to a number of schools and other companies."
While most scientific seismic instruments were priced in the tens of thousands of dollars, the standard Palert cost just shy of $3,300.
"The cost enables a large number to be deployed providing maximum coverage and provide a big data approach to assisting after an earthquake."
The network did not currently cover all of New Zealand, but the company hoped that would change as more companies and organisations joined it.
"This will provide greater granularity of the likely damage," Swasbrook said.
"As an example, Wellington Water currently have over 60 units deployed and are in the process of finishing a project to send the data to our central server.
How the shaking was recorded around the top of the South Island. Image / Jenlogix
"More Palerts are to be deployed for Wellington Water as part of their resilience planning." Another major use of the devices was in rapid structural health analysis.
Installing just three units in a building could determine its structural safety within a minute of a quake.
"The data is also available to engineers via the cloud. This means it is possible to determine which building will need work and those that can be cleared by engineers quickly – saving company downtime."
This map shows how strongly the quake was felt around New Zealand, as reported to GeoNet. The darker the colour, the more severe the shaking. Image / GeoNet
Hutt Valley Hospital used the system both for seismic switching but also to determine if a building needed to be evacuated.
More than 15,600 people around the country reported feeling yesterday's earthquake to GeoNet.
Insurance Council of New Zealand chief executive Tim Grafton was aware of a small number of quake-related claims, all of which were under cap and being managed by EQC.
"We haven't heard of any over cap claims," he said.
"If anyone has suffered damage from the earthquake and is yet to make a claim, they should contact EQC for any home and contents damage and their insurer for anything else."
