Direct Petroleum Exploration Inc (DPE), a Denver-based exploration firm, has said it finished the initial stage of a gas well in northern Bulgaria. Limited flow testing was undertaken on the high pressure Lower Jurassic Ozirovo zone on August 17 at the site of the Deventci R1 well some 150 km northeast of the capital Sofia, the company said in a statement.

Complete control of the well was maintained throughout the operation, which was supervised by senior DPE engineering staff and David Nelson, vice-president of exploration and production, and Kolyo Tonev, manager of Direct Petroleum Bulgaria, a wholly owned subsidiary of DPE.

"This completion represents a major milestone in our Bulgarian operations. While we were unable to conduct a long-term test due to the high-pressure conditions, the well performed as predicted by our modeling of the reservoir, supporting our technical evaluation of this discovery," Nelson said in the statement.

Well flowback was suspended until high-pressure testing and production equipment is flown in form the US in in September, according to the company.

"This is the highest pressure gas reservoir ever encountered in Bulgaria," Tonev said. "Further testing and analysis will be required to fully assess this discovery."

The well is on a geological feature known as the West Koynare structure, wich covers around 15-20 sq km, as defined by seismic and DPE's own proprietary technology.

DPE has business operations in the US, Russia, Bulgaria and Morocco.