More with Less: Channel Fracturing Delivers Improved and Sustainable Production with Less Resources in Low-temperature Reservoirs of Tsarichanskoe Field

Abstract Tsarichanskoe is one of the largest oil fields in the Volga-Ural region of Russia with proven reserves oven 25 million tons of oil equivalent. An ambitious goal to produce up to 2 million tons over the next 5 years was set to achieve. The target formation to produce from is a Devonian reservoir also known as DKT. It is represented by alternation of sandstone, mudstone and siltstone and has challenging properties to deal with such as low permeability and low temperature (60–70C). Economic production from these reservoirs requires an effective stimulation. Conventional hydraulic fracturing in vertical and horizontal wells has been intensively utilized in the field with varying success since the beginning of its development. In some cases, wells completed with conventional fracturing underperform expectations and demonstrate rapid production decline. In other, complex geological conditions restrict treatment size with fracture conductivity being compromised. Therefore, the need exists for a novel stimulation technique capable to perform in the given environment and unlock the reservoir to its full potential. Channel fracturing technique has been successfully deployed in Russia with more than 170 treatments pumped in different fields. The channel fracturing technique creates highly conductive open pathways within the proppant pack by combining specific pumping protocols with fluid and fiber technologies. It is aimed at maximizing fracture conductivity and establishes unrestricted flow of fluids from the reservoir to the wellbore through the network for channels formed by heterogeneous proppant placement. To ensure stability of the channels network, the use of appropriate degradable fiber materials is imperative. The fiber additive has to be chosen based upon specific reservoir temperature. Several treatments were pumped with unique low-temperature fiber among the first trials worldwide. Successful application of low-temperature fiber enabled channel fracturing technology for Tsarichanskoe. Field campaign was supported by extensive laboratory analysis of the fiber to prove its mechanical properties and required functionality for channel fracturing in low temperature reservoirs. Initial production analysis indicates that application of channel fracturing in conjunction with the unique degradable fiber resulted in a sustainable oil rate increase up to 30% in comparison with conventional fracturing. The step change in production was achieved with noticeable reduction in proppant and water consumption by 40% and 15% respectively. Successful deployment of the channel fracturing in Tsarichanskoe field offers new opportunities for effective stimulation of low temperature formations in Russia.