Drilling for oil and gas in active subduction zones is nothing new

A109 Light Utility Helicopter flight with mayor Gisborne City from the air in November 2023.

Opinion

GNS Science declined the opportunity to respond to letters published yesterday — one seeking further information than provided in a GNS letter that ran in Saturday’s paper (Quake risk from drilling tiny), the other critical of the letter, its writer and the organisation’s involvement in New Zealand’s petroleum industry.

First, the further detail sought.

Offshore oil and gas production does take place in active subduction zones around the world, off Peru, Alaska, Indonesia, Java, Trinadad and Tobago, and the Philippines. This ranges from coastal to about 1km deep, which is what could be expected off the East Coast. The most similar tectonic setting is probably the Cook Inlet fields in Alaska, at the eastern end of the Aleutian Arc.

The activity in these areas shows drilling in a subduction zone can be managed and regulated successfully, without the additional risks suggested.

As for the criticism of GNS Science, would that writer prefer it if the country did not have a state-backed research institute specialising in earth and geoscience research and consultancy services?

Together with national and international partner organisations, GNS Science undertakes research throughout New Zealand related to earthquake and tsunami hazards. This includes research into the Hikurangi subduction zone about 40km off our coastline, where the 73km thick Pacific Plate is thrust or “subducted” beneath the Australian tectonic plate.

GNS Science has a track record of scientific excellence stretching back to 1865 and is exactly the sort of agency — with expert local and international knowledge — a nation needs to help minimise environmental risks in a sector like the petroleum industry.

If the writer sees its scientific advice as being overly supportive of the petroleum industry, he should maybe consider if his own view of the risks associated with it might need to be reassessed.

GNS Science’s communications manager responded privately to the “spin doctor” comment by noting that a number of scientists at GNS contributed to the letter.