Project Profile
Location: Northwest part of the Caspian Petroleum Province
Exploration start-up Year: - 1975
Reserves: Undefined
The Karpenskiy licence area is situated in the northwest part of the Caspian Petroleum Province. There are two productive intervals, subsalt and suprasalt, divided by the Kungurian salt, which is a regional seal. The high petroleum potential of the subsalt deposits is supported by discoveries in the marginal parts of the Caspian depression, such as the Karachaganak, Zhanzhol, Kozhhasay, Urikhtau, Kensiyak, Alibekomla, Tengiz, and Astrakhanskoye fields. The Karpenskiy Licence Area is located approximately 150 kilometres from the city of Saratov and the Central Asian Centre pipeline (SAS) runs through the centre of the licence area. SAS connects the Turkmenistan and Kazakhstan gas fields with countries bordering Russia to the West, including Ukraine. In addition, the Mokrous pumping station which compresses gas in SAS is approximately 10 kilometres from the northern edge of the Karpenskiy License Area. The SAS would also provide PGK access to local demand through branch pipelines to European Russia.
Exploration of the Karpenskiy Licence Area has been conducted since 1975 when the Ministry of Geology of the Union of Soviet Socialist Republics (the \"Soviet Union\") approved an exploration programme across the Pre-Caspian depression, following the discovery of the Karachaganak field. Licences covering the Karpenskiy Licence Area were held by entities within the LUKoil Group from August 1996 until May 2006, when the Karpenskiy License was transferred to PGK( a subsidiary of Volga Gas). PGK has negotiated a preliminary 20 year offtake agreement for its initial production. Schlumberger has finished processing and interpretation 3-D seismic on YE block of Karpenskiy License Area. Two spots are identified for drilling. The top of the first structure is located right after thick salt layer at 3000 metres. The second structure (the one which was the initial target) is just below the first structure at 4000 metres.
The company completed the acquisition of 107km2 of 3D seismic over the Yuzhny-Ershovskoye (YE) and 160km2 over the Yuzhny-Mokrousovskoye (\"YM\") structures in summer 2007. The data for YE were processed/interpreted and Grafovskaya#1 (G#1) - the first company\'s deep sub-salt well - was spudded on August 28, 2009. The well reached a depth of 5379 metres (April 2010) and the full string of casing was set (logging suggested a potential 300m thick carbonate reservoir).
Subsequently, the well was tested. Four potential intervals indicated hydrocarbons but proved to be sub-commercial. The company commenced a successful on-going supra-salt drilling programme since 2007. The initial drill stem tests from Well Uzenskaya #1 (which was drilled in 2007) were promising. The well flowed at an equivalent of 788 barrels of oil per day in a drill stem test from Triassic layer. The well was put on production in 2007 but is currently on stand-by as it produces different quality oil than Y-Uz wells drilled in 2008-2009.
Uzenskaya #2 was drillled as an appraisal well to check the boundaries of Uzen field and tested high rates of water in the Jurassic and Triassic layers, confirming good collector properties, but has been liquidated. Y-Uzenskaya #3 was drilled on nearby Cretaceous structure (Y-Uz) in 2008 and yielded excellent results in DST producing ~2000 bbls/day of light oil from Aptian horizon. The well is currently producing ~540bbls a day at 8mm choke of 45 API oil which is sold domestically. Uzenskaya #4 was drilled at the same structure to check the extension of the reservoir to the west; it produced for a while but currently is being readed for a sidetrack. Uzenskaya #5 was completed in 2009 and is producing ~560bbls a day at 7mm choke (it tested more than 4000bbls a day in open hole). Uzenskaya #6 well was drilled as an appraisal well to check the eastern part of the field and initially was not productive (lithological replacement) but was successfully sidetracked and is on production now. Uz#9 was drilled as an appraisal well to check the OWC for the field and is currently being sidetracked.Uz#8 tested commercial rates of oil and were put on production late 2009 but from Albian horizon.
The field is developed with the current number of wells. It will be possible that one or two production in-fill wells will be drilled to bring forward the production curve. There is also an eastern extension of the field (separated by a fault from the main part) which is to be explored with one or two wells. The basic production facilities (gathering/separation unit, storage tanks, loading points, mobile living quarters, electrical generators\' station) were assembled at the wellsite and production started in November 2007. The facilities got fully upgraded in 2008 to accomodate the increase in production. Gas fired generators were installed in 2008 utilising the associated gas to boost production and reduce costs. Four more potential supra-salt structures have been identified on the Karpenskiy licence area and will be explored in a due course (all license comitments were fulfilled). Well V-Uz#7 was drilled on one of the potential structures and identified oil-bearing formation in Jurassic. Well V-Uz#10 was drilled at the crest of the structure and identified a thin oil bearing layer which was found sub-commercial; the well was liquidated consequently.
Operators:
Volga Gas: Operator with 100% interest