Kea Petroleum said it had been forced to suspend operations at one of its wells in the Taranaki Basin off of New Zealand.
The firm said jet pumping and swabbing operations had ceased at the Douglas-1 well and would remain suspended for around two months prior to testing operations restarting.
"Formation water, from extensive fractures within the Tikorangi [block], mixed with fluids lost down hole during drilling operations dominated flow during testing," the firm said.
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"During the suspension the fluid contacts may equilibrate, such that hydrocarbons enter the wellbore."
Kea said experience from several wells in an adjoining field demonstrated that only after allowing the fluids to equilibrate were these wells established as commercial oil producers.
The firm said it would be unable to determine whether the Douglas well would follow this pattern until it resumed testing operations.
Shares dropped almost 14% following the announcement.
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