Experience of fracturing development of carbonate formations at Group of Companies Gazprom Neft

Rationale. The development of carbonate formations by hydraulic fracturing is a very interesting and ambiguous process. Unlike terrigenous objects, reservoir stimulation can be performed by both acid and proppant fracturing methods, and the abundance of technological branches expand the selection options even more. Despite the fact that there is a general concept of choosing hydraulic fracturing technology depending on the geological and physical characteristics of the object, the qualitative choice is complicated by the fact that solutions that produce results at one layer could not show the same efficiency in similar conditions at another formation. Therefore, it is important, from the point of view of working with carbonates, to have as much experience as possible in various well conditions in order to minimize production risks and costs associated with the choice of approach and stimulation technology.

Target: The article shows a technological overview of effective fracturing solutions for carbonate formations, directed to understanding their features and applicability depending on well's and geological conditions. Authors appoint an important place to vision of experience of using stimulation technologies that have found a place and proven themselves at carbonate formations in Gazprom Neft, show the risks and limitations that can be encountered when choosing a particular solution.

Materials and methods: Described an experience in hydraulic fracturing and multistage fracturing, technologies, approaches and their features in depending on geological conditions of carbonate formations.

Results: The article shows the actual experience of using hydraulic fracturing technologies at carbonate formations, their comparative effectiveness, and the most successful practices based on the actual experience of the work performed. Much attention is paid to comparing the effectiveness of acid fracturing, acid-proppant fracturing and variations of fracturing on gelled acid.

Conclusion: The work results given not only an idea of the technological diversity of the types of stimulation of carbonate formations, but also show their comparative effectiveness in geological and physical conditions of the reservoir. Described experience can help in choosing more effective solutions for development of similar formations, reduce risks at early stages of preparation for fracturing and helps in determining the choice of stimulation technology, thereby improving the quality and efficiency of fields development.