Following the completion of the HH-2 Portland pilot well, UKOG has initiated the HH-2z horizontal drilling operations The Horse Hill field is located in Surrey. Photo: courtesy of skeeze from Pixabay. UK Oil & Gas (UKOG) has launched horizontal drilling operations at the onshore Horse Hill field located in the Weald Basin in Surrey, UK.The company has started drilling of the Horse Hill-2z (HH-2z) well with an objective to deliver a 3,200ft horizontal section completely within the most oil productive zone in the Portland reservoir.The horizontal drilling campaign follows the completion of drilling of the Horse Hill-2 (HH-2) Portland pilot well, said UKOG. According to the company, the pilot well’s coring and electric logging programmes further defined the presence and quality of the productive zone in the reservoir.HH-2/2z is the first horizontal well to be drilled in the Portland oil pool of the Horse Hill field.The horizontal well has been designed to be used as a production well in the future. It will have a capability of producing substantially higher flow rates compared to the previously announced 362 barrels of oil per day from the HH-1 vertical Portland discovery well, said UKOG.The company said that after undertaking a planned extensive HH-2z EWT campaign, the HH-2z Portland and the HH-1 Kimmeridge wells are likely to be brought into long term production by the year-end.UKOG chief executive Stephen Sanderson said: “Our confidence in the HH-2z horizontal’s ability to deliver significant flow rates has been further boosted by the pilot well’s better than expected geological results.“Our subsurface team’s focus is now firmly upon steering the well wholly within the target zone, the Portland sweet spot , demonstrably the most oil productive part of the reservoir. I have every confidence we can deliver the desired positive result.”Stakeholders in the Horse Hill fieldLast month, UKOG increased its stake in the Horse Hill field to 85.635% by completing acquisition of Magellan Petroleum (UK) Investment from Tellurian Investments. The acquisition helped UKOG gain Magellan’s 35% direct interest in the Horse Hill oil field, which is contained in the PEDL137 and PEDL246 licences.To develop the onshore oil field, a special-purpose limited company called Horse Hill Developments (HHDL) was created in which UKOG has a direct interest of 77.9%. The remaining stake in HHDL is held by Alba Mineral Resources and Doriemus with the former holding 65% ownership in the Horse Hill field and the PEDL137 and PEDL246 licences.