A drilling survey by US oil analysts Nutech Ltd estimated the 55-square-mile Horse Hill-1 site, part of the Weald Basin oil field, contains some 158 million barrels per square mile, media reported Thursday.
The whole Weald Basin is thought to contain up to 100 billion barrels of oil.
The figure dwarfs the British Geological Survey’s original estimate of just about 4.4 billion barrels of crude.
The new survey showed the area potentially contained a "world class" resource with "significant daily oil production," adding that between 3 and 15 per cent of the reserves were recoverable.
Experts believe the oil could be successfully extracted using conventional horizontal drilling techniques," downplaying the possible use of fracking.
