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LONDON (Alliance News) - Shares in Angus Energy PLC plunged on Monday as the company reported water intrusion during a test of its Brockham X4Z well.
Angus Energy shares were trading down 22% at 5.43 pence. Meanwhile, shares in Alba Mineral Resources PLC, which owns a 5% stake in the licence, were down 7.3% at 0.26p each.
Angus, the operator of the licence, said the well has been perforated from 960 metres to 1,155 metres measured depth and produced in total 280 barrels.
"The well flowed naturally to surface upon the removal of the completion and clean up fluids with flow rates rising steadily as the test continued," the company said.
However, Angus said that "it has become apparent that a part of the perforated interval is producing water", which is inhibiting significant oil flow and therefore has not allowed for sustainable flow rates of oil.
The firm is now looking to isolate the water zone.
Alba Mineral's Chair George Frangeskides said: "Confirmation from Angus Energy that the well has flowed naturally and that oil has been produced to surface are clear positives arising out of the recent test programme at Brockham.
"We look forward to further proposals from Angus in respect of tackling the water influx which they report as having inhibited oil flow, so that we can more readily evaluate the full potential of the Kimmeridge limestones at Brockham."