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(An item published at 1157 BST misstated the chief executive's job title. The correct version follows.)
LONDON (Alliance News) - The companies involved in the Horse Hill prospect in Surrey, England Thursday said they have made an oil discovery at the Horse Hill 1 well in the Weald basin that could be more than double the entire production from the North Sea over the past 40 years.
However there remains big question marks over how much of the oil can be recovered.
Although the exact amount of oil in place is yet to be confirmed by the companies involved as they continue to analyse the discovery, Sky News and the BBC have reported the oil in place could be around 100.0 billion barrels of oil, which is more than double the 45 billion barrels of oil that has been produced in the North Sea in the last 40 years.
However, the amount of oil that will be recovered is expected to be significantly less. The report said the oil in place stands at 158.0 million barrels per square mile over a 653 feet aggregate net pay section, and in an interview with the BBC, UK Oil and Gas Investments PLC Chief Executive Stephen Sanderson said initial estimates show that between 3% and 15% of the total oil in place could be recovered, meaning the discovery could lead to between 3.0 billion to 15.0 billion barrels of oil.
US-based NUTECH Ltd made the 158.0 million barrels per square mile estimation, but said this excludes the upper portland sandstone oil discovery that was previously-reported at 102 feet of Portland sandstone gross oil pay.
"In order to establish estimates of total oil in place within the licence area, the semi-regional resource potential of the Weald basin's eastern footprint is the subject of ongoing analysis under the contracted alliance between Nutech, UK Oil and Gas and Solo Oil. The results of the estimated oil in place within the licence will be reported when completed," said UK Oil and Gas Chief Executive Stephen Sanderson.
Horse Hill Developments Ltd owns a 65% stake in the prospect and the remaining 35% of the prospect is held by Magellan Petroleum Corp.
UK Oil & Gas Investments holds a 30% stake in Horse Hill Developments, whilst Doriemus PLC, Stellar Resources PLC, Solo Oil PLC and Alba Mineral Resources PLC each hold 10% stakes in Horse Hill Developments, with Evocutis PLC holding a 2% stake and the balance is owned by Angus Energy, in which UK Oil & Gas has a 6% stake.
The news saw shares of all companies involved significantly rise Thursday. UK Oil shares more than tripled to 3.47 pence per share, Doriemus shares leapt 76% to 0.146p, Stellar Resources rose 72% to 0.732p, Alba shares more than doubled to 0.975p and Solo Oil climbed 24% to 0.721p. Evocutis shares were up 31% to 0.268p. All were among the best performers in the AIM All-Share.
By Joshua Warner; joshuawarner@alliancenews.com; @JoshAlliance
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