‘Game-Changing’ Horse Hill-1 Well Produces ‘North Sea-like’ Oil Flows

UK Oil & Gas Investments plc announced Monday that the final production test at the Horse Hill-1 discovery, onshore the UK’s Weald Basin, flowed oil at a stable rate of 323 barrels per day, bringing the final total aggregate stable dry oil flow rate from two Kimmeridge limestones plus the overlying Portland sandstone at the well to 1,688 bopd.

Over the 30-90 hour flow periods from each of the three tested zones, no clear indication of any reservoir pressure depletion was observed, according to UKOG. Further analysis of data is currently ongoing and UKOG has commissioned Nutech to investigate a possible upgrade to the oil in place calculated within all three test zones together with engineering studies to examine possible flow rates from a horizontal well.

Reservoir engineering analyses by Nutech and Xodus are also underway, and will likely result in an estimation of potential recoverable volumes. Results of these studies will be reported “shortly”, and preparation is now underway to obtain regulatory permissions to conduct extended production tests from all three zones at the site, followed by a horizontal sidetrack in the Kimmeridge and a possible new Portland development well.

Commenting on the latest results from Horse Hill-1, Stephen Sanderson, UKOG’s executive chairman, said in a company statement:

“The flow test results are outstanding, demonstrating North Sea-like oil rates from an onshore well. This simple vertical well has achieved an impressive aggregate oil rate equivalent to 8.5 percent of total UK onshore daily oil production. The Portland also has greater flow potential as rates were limited by the test pump’s maximum capacity. Further significant flow rate improvements may be achieved from all zones using horizontal sidetracks during future planned operations.

“These results also cause us to rethink and recalibrate many prior geological assumptions. Nutech will now reinvestigate the presence of significant natural fracturing and oil in place figures for both the Portland and Kimmeridge units given that all flow periods produced 100 percent dry oil.

“Most importantly, this well has proven that the new Kimmeridge oil play is a reality within our license interests. Whilst there is still much work to be done, this test has moved the project into a potential commercial reality. The Horse Hill license owners remain committed to ensuring that any resultant future commercial operations will respect the rural beauty of the Weald basin and the way of life of local residents.

“In a wider sense, whilst it is absolutely correct for us all to press for low cost, renewable sources of electrical energy, we must be mindful that oil fills a very different strategic role. Oil is not used for electrical power generation but fuels all transport and the manufacture of essential everyday products, such as plastics and pharmaceuticals. Oil provides the vital feedstock for components that are essential for all industrial sectors. We are delighted, therefore, that this discovery has the serious prospect of being a meaningful addition to the UK’s own supply of oil in a period where North Sea production is declining more rapidly than expected.”

Solo Oil Chairman Neil Ritson was equally excited about the potential of the well, stating in a Solo release:

“This is truly a game changing well for exploration in the Weald Basin and provides considerable encouragement that a significant commercial accumulation has been found in the Portland sandstones and that a potentially massive Kimmeridge limestone play has been revealed. Solo looks forward to further results from the tests and future plans to produce the discovery and further explore the potential of the Kimmeridge play.”

In an independent report last year, Schlumberger calculated that 10.993 billion barrels of mean oil in place was imbedded within the 55 square miles of the PEDL137 and PEDL246 Horse Hill licenses. Schlumberger’s estimates build on the company’s previous petrophysical evaluation of the Horse Hill-1 well, located in PEDL137 near to London Gatwick Airport, which estimated the gross OIP for the Jurassic section of the UK’s HH-1 well to be approximately 271 million barrels of oil per square mile.

The Horse Hill-1 discovery well, completed in November 2014, is the first modern well since the 1980s to test the entire Jurassic and Triassic section of the Weald Basin, reaching Palaeozoic basement at around 8,500 feet. Oil flows in excess of 900 barrels per day and 463 bpd were recorded from previous tests Horse Hill-1.

UKOG owns a 20.163 percent interest in PEDL137, with Solo Oil holding a 6.5 percent stake.

RIGZONE