A slip on the access road into Frasers pit at Oceana Gold's Macraes site, which restricted access to high-grade ore for 16 days, is not expected to impact on overall gold production this year.
In its fourth quarter report, chief executive Mick Wilkes said a ''major movement of the footwall'', which has been subject to frequent movement during the previous 16 years, was triggered by heavy rainfall.
''The ground movement resulted in restricted access to high grade ore at the base of the pit for a period of 16 days,'' until early January, Mr Wilkes said.
Mining continued unaffected in other areas of the open pit.
Monitoring systems gave ''ample warning'' of the higher rate of movement and all staff and equipment was evacuated from the pit and the underground Frasers mine, the entrance to which is at the bottom of the pit, ''without harm'', he said.
While an update on the event will be provided ''in due course'', it was not expected to affect Mr Wilkes' earlier overall production guidance for 2013 of 285,000oz to 325,000oz, but the interruption may be reflected in first quarter production figures.
Gold during 2013 was estimated to be produced for a cash cost of $US650 to $US800 ($NZ775 to $950) an ounce, net of copper by-product credits from Oceana's gold and copper mine in the Philippines.