Scientists will start dropping 100 borrowed but especially-made seismometers into the ocean off the North Island coast next week to learn more about the earthquake and tsunami risks in the region.
The eastern coast has been under increased scrutiny as scientists warn of a potentially devastating "megathrust" earthquake which could release 2000 times more energy than the 2011 Christchurch earthquake that killed 185 people.
It will be New Zealand biggest use of seafloor earthquake recording instruments, with New Zealand scientists being joined by specialists from Japan, the US and the UK.
Focusing mainly on the more northern Hikurangi Subduction Zone, the seismometers will be dropped from Wairarapa to the East Cape.
After a recent confirence in Napier, GNS Scientist Dr Laura Wallace warned the area had "the potential to produce the world's largest earthquake and tsunamis".