Gazprom Neft has launched drilling the first horizontal well to explore the Bazhenov formation of the Palyanovsky deposit at the Krasnoleninsky field, marking a new stage in the study of shale oil deposits.

      According to the official statement, the depth of the first well exceeds 3,200 metres and the horizontal borehole extends approximately 300 metres. Three-stage hydraulic fracturing (fracking) will be performed at the deposits in order to increase efficiency. Overall, it is expected that four wells will be drilled during the new phase of the project in 2014-2015, increasing the length of the horizontal sections in consecutive stages and also increasing the number of fracking stages.”

      In 2013-2014, Gazprom Neft drilled 5 controlled-directional wells, involving the use of fracking at four of these. “Commercial oil flows were achieved in all of these wells, which continue to be in operation. Furthermore, these operations confirmed the possibility of effective fracking at the Bazhenov complex. The next stage of the project will determine the most effective method for extraction,” the press release goes on to say.

      "The Bazhenov formation is an example of our work with non-traditional deposits, which is an area the Company is focused on developing. By implementing pilot projects we determine the optimal method for working with these resources in order to develop further projects effectively," said Vadim Yakovlev, First Deputy CEO of Gazprom Neft.

      According to the corporate website, shale oil is present in the “Bazhenov, Abalak and Frolov formations – Western Siberian rock formations with extremely low permeability, but high oil saturation”.

      The Bazhenov formation is a stratum of rock which has been identified in the central area of Western Siberia at depths of 2,000-3,000 metres. It covers an area of around 1 million square kilometres, but is comparatively thin – between 10 and 40 metres thick. According to some estimates, the oil reserves in the Bazhenov formation reservoir may reach 100-170 billion tonnes in Western Siberia alone.

      The Abalak formation consists of marine shoreline or marine deposit rocks; it underlies the deposits of the Bazhenov formation with which it is sometimes in abrupt contact. The Abalak formation extends across the Krasnoleninsky arch, as well over as the Surgut oil and gas district and the Uvat region. The deposits within the boundaries of the Krasnoleninsky arch are 2,200-2,400 metres deep, and their total thickness varies from 20 to 90 metres.