Albania Onshore Oil Field
Europe’s largest onshore oil field, the Patos-Marinza in southern Albania, has been given a new lease on life after seeing production soar from 600 B/D just over a decade ago to more than 20,000 B/D this year. The field’s sole operator, Canadian-based Banker’s Petroleum, set up shop in the country in 2004 and has also more than doubled the estimated reserves from 98 million BOE to 220 million BOE. The Patos-Marinza, which holds an estimated 5 billion bbl of oil in place, has undergone a transformation from a heavily polluted oil field with outdated technology to one that exemplifies modern operations and environmental practices.
Chris Thompson, a production engineering manager at Banker’s, said the company has deployed a number of strategies to achieve its production goals. They include the wholesale replacement of existing artificial lift systems, infill drilling with horizontal wells, and the recent initiation of enhanced oil recovery (EOR) pilot programs using polymer and waterflooding. “With the way the field is set up, there seems to be unlimited opportunities,” Thompson said.
From the onset, Banker’s strategy has centered on introducing Albania to heavy oil engineering expertise and modern technologies from Alberta, Canada. Though similar in some ways, there are plenty of differences between the two areas that make the Patos-Marinza a much different operating environment.
For starters, the gravity of the oil is as low as 4 °API and an average of 8 °API. In Canada, oil this heavy would require the use of steam to get flowing. But because the Albanian reservoir is deeper, the higher pressures and temperatures allow the viscous oil to flow on its own into the wellstream.
By using pad drilling, Banker’s is able to tap into multiple horizons at different depths with as few as one and in some cases more than 20 horizontal wells from a single site. Depths for the horizontal wells range from approximately 1,100 m in the shallow end of the field to 1,600 m in the deeper part and have an average lateral section of approximately 600 m in length. The target formations are made up of unconsolidated sands that allow the oil to migrate into the wellstream. This means that unlike a tight shale resource play, in this field hydraulic fracturing is not needed to stimulate the reservoir.
And since the European oilfield service market is not set up to support onshore heavy oil development, Banker’s imports most of its equipment from Canada, which can take months in some cases. So to avoid project delays, the company has made supply chain operations a big focus of its strategy.