Gnawing sharks disrupt seismic survey

A shark attack on the multimillion-dollar streamer being towed by the Norwegian vessel Pacific Titan has set the Government-financed seismic survey off the East Coast back by several days.

The streamer is used to receive information about seismic activity on the seabed.

The 12km-long streamer was cut when sharks chewed through the reinforcing, leaving the wiring exposed.

A 2.5km section of cable was severed and floated free for about 12 hours until a chase vessel from Napier could reach the area, about 100km east of Gisborne.

It is the longest streamer used in New Zealand waters.

A Crown Minerals spokesman for the Ministry of Economic Development, Tim Allan, said the streamer had flotation devices, which were automatically activated when the cable was severed.

High winds and rough sea meant the crew could not retrieve the detached section.

"The Pacific Titan circled round the floating streamer for approximately 12 hours while the chase vessel deployed from Napier," Mr Allan said.

"The chase vessel was able to hook the detached streamer and towed it to calmer waters in Hawkes Bay, where the tow cable was transferred to the Pacific Titan and it was retrieved."

Technicians repaired or replaced the damaged sections and the streamer was redeployed.

The survey is the first of its kind under a $15 million fund established by the Government last year as part of a package to lift exploration in New Zealand.

It will cover a 100,000sq km area from Te Kaha to the Wairarapa Coast and extend as far as 360km north-northeast of East Cape.

The survey, which began last week, is expected to cost between $6 million and $7 million and take about six weeks.

- NZPA