What lies beneath Kaiko¯ura’s seabed?

Mapping Kaiko¯ura and Marlborough’s earthquake-damaged coastline will reveal changes beneath the surface and could help scientists figure out what sea life may live there.

Land Information New Zealand (LINZ), with survey companies IXSurvey and Discovery Marine, would re-map the seabed between Kaiko¯ura and Cape Campbell.

‘‘For the next few months we’ll have two boats sailing round the coast using state-of-the-art multibeam sonars to map nearly 35,000 hectares of the seabed,’’ hydrographic surveyor Annette Hadler said.

The sonar would use a pulse of sound to measure the water depth.

The results would reveal the shape of the sea floor, hazardous rocks and reefs and what the seabed was made of to help scientists guess what might live there.

The November 2016 earthquake raised parts of the Kaiko¯ura seabed by more than a metre. Coseismic movement, the seismic release of energy along a fault, was behind the seabed lift.

‘‘LINZ regularly carries out hydrographic surveys to ensure the nautical charts are up-to-date and accurate. For this project we’re also working with [the Ministry for Primary Industries] to understand how the changes may have affected marine life in the area,’’ Hadler said.

‘‘We know from earlier surveys that there have been changes to the seabed in the upper South Island following the November 2016 earthquake. We expect this work will give us a more detailed picture of them.’’