OREANDA-NEWS. Gazprom Neft has begun drilling of three exploratory wells at its Chonsky project in Eastern Siberia — one each at its Ignyalinsky, Vakunaysky and Tympuchikansky fields. Drilling of a further well at the Tympuchikansky block will begin within a month. Data obtained from further well testing will allow the clarification of geological models of the fields, allowing the various blocks to be subsequently prepared for production drilling. Pilot works (in the order of 600 square kilometres) involving the use of high-accuracy UniQ seismic technology were also completed in mid-March: some 450 square kilometres of full-azimuth 3D seismic is also planned for April. 

The Gazprom Neft Chonsky project covers three fields: the Ignyalinsky, Vakunaysky and Tympuchikansky fields, located at the border of the Irkutsk Oblast and the Sakha Republic (Yakutia). On the basis of geological prospecting undertaken last year, Gazprom Neft has been able to increase estimated reserves at the Chonsky project by a further 50 percent — total C1 and C2 reserves across all three blocks now exceeding 210 million tonnes of oil and 270 billion cubic metres of gas. 

Gazprom Neft is continuing geological prospecting at its Chonsky fields to allow the transfer of further reserves from category C2 (probable reserves) to C1 (commercial reserves). A key objective in 2015 will be the preparation of the most thoroughly researched blocks for production testing, expected to commence next year.

Victor Sorokin, CEO, Gazpromneft-Angara, commented: “Gazprom Neft has been actively developing the Chonsky project since 2011. The drilling of prospecting and exploratory wells clarifies our understanding of the geological structure of complex deposits in what is a very under-researched region. Continuation of the geological prospecting programme will allow remaining geological uncertainties on this project to be dispelled, and the level of recoverable reserves to be increased. The 2014–15 polar season has also witnessed an industry record in terms of seismic operations at the Gazpromneft-Angara licensed blocks, with 4,200 separate pieces of physical data recorded in the course of a single day.”

Licenses on the Ignyalinsky, Vakunaysky and Tympuchikansky blocks are held by Gazprom Neft subsidiary Gazpromneft-Angara. Specialists from this organisation completed their interpretation of seismic data, obtained through the use of innovative UniQ technology, in 2014. A total 66 prospecting and exploratory wells have been drilled throughout the three fields of the Chonsky project, and some 2,750 square kilometres of 3D surveys undertaken.

UniQ technology is a unique combination of geophysical equipment and supporting software, for high-resolution seismic operations. The data captured through the application of this technology exceed similar volumes of information, obtained through the application of traditional 3D seismic methodologies, by a factor of 10. High-precision geological models of oil-bearing formations built with UniQ technology can be used successfully throughout the entire period of field development, the data obtained allowing further clarification and detailing of geological models without repeated geophysical operations, requiring only the application of new well data.