A "very significant" reservoir of oil was uncovered during a pilot program in British waters west of the Shetland Islands, a British-based company said Friday.

"A very significant hydrocarbon column of at least 2,000 feet is present" in the Lancaster field in British waters, Hurricane Energy said in a statement. Robert Trice, the company's CEO, said the pilot well confirmed a column of oil that was more extensive than the company first estimated.

"Our initial assessment of the well results, which are subject to refinement of the provisional data, suggest that the Lancaster field is likely to be significantly greater than the 200 million barrels," he said.

Preliminary testing yielded a natural flow rate of 6,600 barrels of oil per day, with a maximum artificial rate of 11,000 bpd.

Many of the fields in regional waters are reaching the end of their life span. Regional company Premier Oil this year announced oil was flowing from its Solan field about 85 miles off the coast of Shetland and is on pace to reach a production rate of between 20,000 and 25,000 bpd at some point this year.

Premier said the Solan project was "challenging" because of rough weather conditions in the area and pressure from lower oil prices. Hurricane, for its part, said the next stage of operations would involve the drilling of a horizontal well in the Lancaster field.

Production rates using horizontal wells have the potential to be seven times greater than vertical wells. An offset, however, is higher drilling costs.

Hurricane could unveil further progress when it releases interim results later this month.