It is believed rockslides within the canyon could trigger tsunamis, affecting Wellington’s coastline.

But Marine Geologist Dr Joshu Mountjoy says the chances of that happening are unknown.

He says the scientists are working on a project to understand how often rockfalls occur, and will build models to see whether or not they are capable of producing a tsunami.

Dr Mountjoy says the canyon is 1800 square kilometres in area, with depths reaching up to 3000 metres in places.

– NewstalkZB

Image / Huge waves hit Cook Strait in 2009, Sam Hall