Reserve Replacement by Region
Rosneft’s reserve increases in Western Siberia amounted to 243.9 mmt of oil and gas condensate and 86.9 bcm of gas. 58 exploration wells were completed and tested with a success rate of 92%. 3D seismic surveys totalled over 4.2 thousand sq km. Four fields and 73 new deposits were discovered with a total of 54 mmtoe in АВ1С1+В2С2 reserves.
RN-Uvatneftegaz is consistently implementing the strategy to develop the Uvat project, including by ensuring the annual growth rate target for recoverable reserves. In the reporting period, significantly more oil reserves were discovered than extracted. In 2019, the increase in RN-Uvatneftegaz’s АВ1С1 reserves (24.7 mmt) exceeded production (10.3 mmt) by 240%.
In 2019, two new fields were booked in the Russian State Register of Mineral Reserves: Sosnovoye (Yugansky 12 licence area) and Matusevich (Yugansky 11 licence area) with a total of 6.9 mmtoe in recoverable AB1C1+B2C2 reserves.
Drilling of an exploration well at the Kirilkinskoye field (Tamarginsko-Severo-Bolotny licence area) confirmed the prospects of a new oil and gas pay in the pre-Jurassic deposits of the Uvat project.
In 2019, RN-Nyaganneftegaz recorded reserve replacement of 194% in the licence areas of the Krasnoleninsk Code of Fields.
In actively developing its gas business, Rosneft carried out 3D seismic surveys of 729 sq km at its Western Siberian gas assets in 2019, as well as completed and tested three wells. In 2019, Rosneft’s gas reserves in Western Siberia grew by 86.9 bcm.
The Company continued study of the unconventional gas-saturated reservoir of the Berezovskaya suite in Western Siberia. In 2019, Rosneft developed a unique technology to tap into hard-to-recover dry gas reserves in the low-permeability opoka-like siliceous reservoirs of the Berezovskaya suite. Rosneft initiated the creation of a working group under the auspices of the State Commission for Mineral Reserves (GKZ) of the Federal Subsoil Resources Management Agency (Rosnedra) and in partnership with major Russian companies to prepare a Single Interim Methodology for assessing the volumetric estimations and gas recovery rate for the deposits of the Berezovskaya suite. Following well testing in the Berezovskaya suite interval in 2019, the increase in recoverable B1C1+B2C2 gas reserves amounted to 30.5 bcm.
As part of the Gydan Peninsula study in 2019, the interpretation of 3D seismic surveys of the Minkhovsky licence area confirmed the field potential and verified the location of prospecting and exploration wells. Drilling preparations are currently underway. A new gas cluster will be created based on the Minkhovskoye field.
In 2019, total reserves growth in Eastern Siberia and the Far East was 101.2 mmt of oil and gas condensate and 185.4 bcm of gas. 18 exploration wells were completed and tested with a success rate of 94%. 2D seismic surveys of 1.8 thousand linear km and 3D seismic surveys of 1.2 thousand sq km were completed. One new field and seven new deposits were discovered with a total of 9 mmtoe in АВ1С1+В2С2 reserves.
At Verkhnechonskneftegaz, testing of eight exploration wells in licence areas in the Katangsky district of the Irkutsk Region confirmed the industrial oil and gas bearing potential with an exploration drilling success rate of 100%.
A well in the Preobrazhensky licence area, drilled near the Severo-Danilovskoye and Lisovsky fields, demonstrated a record flow rate of 582 cub m per day of waterless oil. The location of exploration wells was selected based on advanced technologies to process 2D and 3D seismic data. All wells were drilled using a fundamentally new geological approach. Based on the testing results of exploration wells, the Company will soon submit a report to the State Commission for Mineral Reserves to record the new field reserves in the State Register of Mineral Reserves.
Rosneft expanded the AB1C1 reserves of the Verkhnechonskoye oil and gas condensate field (within the Verkhnechonsky licence area) by a total of 51.8 mmt of oil and gas condensate and 66.4 bcm of gas. This was possible due to effective exploration, advanced data processing system, and application of innovative technologies.
In 2019, we determined the location of the first exploration wells in the Khatanga cluster on the Taimyr Peninsula based on the results of large-scale seismic surveys conducted in 2018.
In the reporting year, the Company obtained a licence for the Zapadno-Irkinski licence area, along with the major fields of the Vankor cluster.
In 2019, Rosneft continued drilling multilateral exploration wells in the Krasnoyarsk Territory to confirm productivity of structurally complicated carbonate and fissured reservoirs and increase the deposit area. Using more sophisticated wells in complex geological conditions made it possible to achieve the target reserves growth, update the geological model, and eliminate geological risks for production drilling. The Company decided to roll out the technology for structurally complicated carbonate reservoirs in Eastern Siberia.
In the Tersko-Kamovsky licence area (north-eastern section), the vertical shaft of the appraisal well was drilled, completed and tested in 2019. Testing in the Riphean dolomite stratum resulted in the oil rim discovery of the Madrinskaya deposit, Block 1. The obtained flow helps estimate the oil bearing capacity of the Madrinskaya block 1 as a whole, which potentially allows the Company to register 39.7 mmt of oil in the B1C1+B2C2 reserves in the State Register of Mineral Reserves. The drilling results will increase the resource base of Slavneft-Krasnoyarskneftegaz and Vostsibneftegaz.
Currently, the well is being sidetracked subhorizontally to obtain more accurate information on the extraction potential of the area for subsequent drilling through a grid of horizontal production wells.
In 2019, reserves in the Volga-Urals Region, Timan-Pechora, and Southern Russia increased by a total of 77.9 mmt of oil and gas condensate and 7.8 bcm of gas. 67 wells were completed and tested, with a success rate of 84%. 3D seismic surveys totalled 3.6 thousand sq km, while 2D seismic surveys totalled 0.8 thousand linear km. 17 fields and 177 new deposits were discovered with a total of 282 mmtoe in АВ1С1+В2С2 reserves.
In the Samara Region, the Company continued exploration of Domanic deposits for siliceous limestones. At the Leshchevsky and Neprikovsky licence areas, three pilot wells were drilled and completed, with one of them completed and tested. The Company plans to drill additional wells to prepare a conclusion on the commercial potential of these deposits in the licence areas in the Samara Region.
The new field discoveries were made possible by the successful implementation of the exploration programme by Orenburgneft and Bashneft-Dobycha. The Company discovered 15 fields and 123 new deposits. An important discovery by Orenburgneft was the Zapadno-Dolgovskoye field within the Buzuluk subsoil area. Based on the drilling results of appraisal well No. 444, the recoverable B1C1+B2C2 reserves in the field are estimated at 7.6 mmtoe.