The Tui oilfield is expected to produce about 41% less over the next year, reflecting the natural decline of the field and the shutdown of one of its four wells.
New Zealand Oil & Gas, which owns 12.5% of the offshore Taranaki field, says the operator estimates 2.8 million barrels will be produced in the year to June 2011. Last year's output was 4.8 million.
The company also says the Pateke-3H well is not producing, as it needs parts and a rig to fix a problem injecting gas into the field, which helps push the oil out.
It estimates that it may be towards the end of the year before the well is fixed, though it depends on when the parts can be delivered and a rig is available.
