A worker collects crude oil sample at an oil well operated by Venezuela's state oil company PDVSA in Morichal July 28, 2011
After reporting it was pumping "significant" amounts of oil from a test well in the middle of last month, UKOG and its partners on Tuesday announced that a subsequent test well in the area had pumped almost double the amount previously unearthed - and all without need for much mechanical pumping.
UKOG, which owns just shy of 20% of the Horse Hill-1 field near Gatwick, said previously it had managed to pump the equivalent of around 463 barrels of oil per day for just over seven hours.
But on Tuesday the company and its partners announced that a new test drill in an area of limestone had successfully pumped oil at an average rate of 900 barrels of oil per day. What's more, the oil "started flowing freely to surface, without pumping," at points during the test drill.
Two limestone test drills in the so-called Upper Kimmeridge area of the field have now produced a combined average stable rate of over 1,360 bopd (barrels of oil per day.)
UKOG CEO Stephen Sanderson says in Tuesday's statement (emphasis ours):
This test provides unequivocal proof of concept for the Company's new Kimmeridge limestone oil play. The two Kimmeridge flow tests have not only shown that moveable oil exists within the Kimmeridge, but more importantly, that it can be extracted at commercial rates even from vertical wells without significant stimulation.
This result is therefore very significant for the company and the Weald Basin of the UK. The Kimmeridge play has moved from science project into the zone of commercial reality.
The well's natural aggregate flow rate from the Kimmeridge limestones of 1360 bopd looks to be one of the highest natural flow rates recorded in a UK onshore wildcat well since the Wytch Farm discovery in the 1970s. It should be noted that the planned use of horizontal appraisal and development wells may further significantly enhance production flow rates seen to date.
In April last year, UKOG revealed that it discovered about 100 billion barrels of oil near Gatwick Airport. Independent analysis confirmed two months later that there is a whole glut of oil underneath the ground in the Horse Hill-1 oil field.