An exploration of the undersea fault that caused last year's devastating Japanese earthquake is likely to help the understanding of severe jolts here.
Otago University geologist Dr Virginia Toy was heavily involved in the project, which involves scientists drilling to record depths to find out how faults work.
"We can look at hundreds of potentially active faults on-land in New Zealand and say 'oh, these materials look like this or they look like this, and therefore this fault is likely to behave in this way'," she said.
Toy joined the two-month exploration of the fault that caused last year's Tohuku earthquake and tsunami.
By studying the colliding plates, it is hoped New Zealand can learn more about how the country's faults behave, including those that caused the deadly Christchurch quakes.
"Sometimes smallish earthquakes like the Christchurch sequence generate a lot of ground shaking, huge amounts of damage," Toy said.
"Much larger quakes like Tohuku, or the Fiordland quake that happened in 2009, generate significantly less ground shaking even though they are larger magnitude events."
When plates move against each other smoothly there's not much seismic activity, but when there's resistance friction the fault eventually breaks and an earthquake occurs.
Toy says with information from the expedition scientists may be
able to refine estimates of how much will the ground shake, however
predicting when earthquakes will occur will never be an exact