NZDF Survey Determines How Much Kaikoura Sea Floor Lifted During Quake

Members of the New Zealand Defence Force hydrographic survey team on the water in Kaikoura.
Members of the New Zealand Defence Force hydrographic survey team on the water in Kaikoura.

16 March 2017

A survey by the New Zealand Defence Force (NZDF) has determined the extent of Kaikoura’s sea floor lift during November’s 7.8-magnitude earthquake.

Lieutenant Commander Philip Davies, who led the eight-member Royal New Zealand Navy hydrographic survey team, said the results indicated that the sea floor had risen by an average of about a metre in the area surveyed.

“Because the actual depth of the sea floor is less than what had been charted, mariners should continue to navigate with caution in the area until revised charts are published,” Lieutenant Commander Davies said.

“We also found a rock in the South Bay of the peninsula that is not shown in previous charts. The rock has a shoal depth of seven metres in a surrounding depth of 15 metres.”

Land Information New Zealand (LINZ), which produces navigation charts and information, has used the survey results to update the information provided to mariners.

Adam Greenland, national hydrographer at LINZ, said the survey results would also be used for LINZ’s long-term plan to resurvey and update the nautical charts for the wider Kaikoura area.

“The information that the NZDF has gathered is important in helping LINZ keep mariners safe and supporting tourism in the region,” Mr Greenland said.

“This part of the coast is used a lot by the cruise industry. This survey means we can give them and others up-to-date navigation information so they can continue to operate safely.”

The NZDF mobilised 815 personnel, 11 aircraft and four ships to support the Government’s disaster relief operation in Kaikoura after the earthquake. Three foreign warships, in New Zealand in November to take part in the Navy’s 75th anniversary, also diverted to the seaside community to help the relief effort.

This page was last reviewed on 16 March 2017.