As of May 15, the first batch of group energy-storing fracturing wells at Xinjiang Oilfield's First Production Plant (Hongshan Company) have shown impressive production performance after being put into operation. Among them, five wells are producing by natural flow, with a daily incremental oil production of 15 tons across the well group and an average daily increase of 1.7 tons per well.
The Keshang Formation reservoir in the Hong60 well area of the First Production Plant is a lithology-controlled structural reservoir, representing a typical medium-porosity, ultra-low-permeability reservoir with complex geological conditions. The block contains 29 oil and water wells, but due to a large well spacing of 350 meters, water flooding efficiency has been poor. Conventional fracturing measures have gradually lost effectiveness, resulting in a recovery factor of only 7.8% and significant remaining potential.
To overcome this development challenge, the First Production Plant developed a "multi-stage, grouped" energy-storing fracturing strategy based on geological parameters, implementing fracturing in four rounds across 15 wells—13 fracturing wells and 2 energy-storage wells. Using material balance methods, injection volumes were differentially designed, supplemented with 0.2% surfactant to enhance displacement efficiency. The total estimated fluid injection volume will reach approximately 150,000 cubic meters, averaging 10,000 cubic meters per well. Additionally, a combined technique of "in-fracture temporary plugging + fracture tip diversion" was applied, along with a 90-day shut-in period for fluid replacement, effectively expanding the fracture coverage area.
After implementation, the measures yielded remarkable results. In the first round, the average injection pressure of three wells increased by 1.8 MPa, indicating effective restoration of formation energy. During the second round’s energy storage phase, pressure indices and fill degrees of wells 0325 and 0331 steadily rose, while the fill degree of Hong85 well increased rapidly by 20.5% after adding temporary plugging agents. After production commenced, the block’s daily oil output steadily rose from the original 6 tons, with some wells experiencing leapfrog growth in production and continuous reduction in water cut, confirming the technical feasibility.
