A team on a science research vessel are investigating what lies underneath the seabed.
A high-profile and expensive international research ship is heading south via Canterbury to search for new information about climate change.
The Joides Resolution (JR), a former oil industry drilling ship, was in Lyttelton Harbour on Thursday and would depart for Antarctica later this week to drill into ocean sediments in the Ross Sea. The vessel has just spent six weeks drilling into the Hikurangi fault near Gisborne.
New Zealand contributes about US$300,000 (NZ$423,000) annually to the US$150 million International Ocean Discovery Program (IODP), which operates the science aspects of the hip's voyages.
The programme has also drilled into the crater formed when a comet struck the earth near Mexico 65 million years ago.
The contribution earned New Zealand one "seat" on the JR once a year, but because the ship's voyages were clumped geographically, New Zealand got three seats on the ship while it was in the South Pacific.
Two Kiwis led the drilling off Gisborne and a third is heading up the Antarctic drilling programme.
"We're leveraging a massive amount of science out a small contribution," Niwa marine geologist Dr Philip Barnes said.
International interest in New Zealand's undersea geology brought the ship here.
The northern part of the Hikurangi subduction zone was notable because of slow-slip events, he said. While earthquakes were caused by sudden movement along faults, slow slips featured bursts of movement that lasted weeks or months.
They did not cause damaging earthquakes, but their behaviour was not well understood, including what triggered slow slips to become earthquakes.
Slow slip events were discovered only 15 years ago and the Hikurangi fault was notable internationally because the slips there were happening at the shallowest known depth, Barnes said.
The drilling rig on the Joides Resolution could reach them, which was why the 23-country consortium that runs the science programme selected the project for funding, he said.
\While off Gisborne, the ship also probed areas featuring undersea landslides, which could be triggered by earthquakes and cause tsunamis.https://www.stuff.co.nz/science/100304858/science-ship-in-lyttelton-lots-of-research-from-nzs-small-contribution4