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UKOG: update on Horse Hill-1 flow test

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Oilfield Technology,

UK Oil & Gas Investments PLC has announced that Horse Hill Developments Limited (HHDL) has informed the company that 100% dry, 40 degree API, light, sweet oil has flowed freely to surface, without pumping, at an average stabilised rate in excess of 900 bpd from an 88 ft aggregate perforated zone within the Upper Kimmeridge limestone interval at a depth of approximately 840 m below ground level.

Restricted flow of 100% dry oil, through a 1 in. choke, using a rod pump, commenced at around 1350 hrs GMT yesterday at an initial instantaneous rate in excess of 700 bpd. At circa 1430 hrs the well started flowing freely to surface, without pumping. The free flow rate increased to over 900 bpd at 1500 hrs. The flow of dry oil then stabilised from 1500 hrs to approximately 1800 hrs, at rates averaging in excess of 900 bpd.

Note that as a consequence of flow initialisation via rod pump, the initial natural flow rates stated above were further restricted by the rods within the 2 and 7/8 in. production tubing.

The well was shut in at approximately 1830 hrs yesterday. The well was opened and free ‘natural’ oil flow recommenced at 2234 hrs yesterday. The well was flowed to obtain a further stabilised flow period and reservoir engineering data. A further update will be provided once this new data is available.

With this stable Upper Kimmeridge limestone flow, the two Upper Kimmeridge and Lower Kimmeridge limestone intervals have now produced a combined average stable rate of over 1360 bpd.

As previously announced, on completion of this Upper Kimmeridge test, operations will move to the shallower Portland sandstone zone at approximately 615 m below ground level.

Further reservoir engineering studies

The company has commissioned Xodus Group Ltd. to evaluate and interpret the reservoir engineering data collected in the Lower Kimmeridge limestone flow test as reported on February 16 and 17. The results will be reported once available.

Horse Hill-1 Discovery Well and Licence

The exploration drilling phase of the HH-1 discovery well was originally completed at the end of 2014. The well is located within onshore exploration Licence PEDL137, on the northern side of the Weald Basin near Gatwick Airport. UKOG owns a 19.968% interest in PEDL137.

Stephen Sanderson, UKOG’s Executive Chairman commented:

“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 bpd 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.

Following the final flow test in the overlying Portland, HHDL now plan to move full speed ahead to obtain the necessary permissions to return to the well, drill a horizontal sidetrack and conduct long term production tests.”

UKOG's interest in Horse Hill

The HH-1 well is located within onshore exploration Licence PEDL137, on the northern side of the Weald Basin near Gatwick Airport. UKOG owns a 30% direct interest in HHDL and a 0.72% interest in HHDL via its 6% interest in Angus Energy Limited. HHDL is a special purpose company that owns a 65% participating interest and operatorship of Licence PEDL137 and the adjacent Licence PEDL246 in the UK Weald Basin.

Adapted from a press release by Louise Mulhall

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