长庆油田陇东地区页岩油水平井细分切割压裂技术

长庆油田陇东地区页岩油储层脆性指数低、天然裂缝不发育、不易形成复杂缝网,进行分段多簇体积压裂时,受储层物性、地应力、各向异性及水力裂缝簇间干扰等因素影响,簇间进液不均,达不到储层均匀改造的目的.针对该问题,依据缝控储量最大化原则,在分级评价页岩油水平段储层品质及建立非均质地质模型的基础上,开展了基于甜点空间分布和综合甜...

Subdivision Cutting Fracturing Technology for Horizontal Shale Oil Wells in the Longdong Area of the Changqing Oilfield

The shale oil reservoirs in the Longdong area of the Changqing Oilfield are characterized by low brittleness index and undeveloped natural fractures. In this case, complex fracture networks are difficult to form. During multi-stage and multi-cluster volumetric fracturing, uniform reservoir stimulation is hard to achieve due to various effects of reservoir properties, in-situ stresses, anisotropy and inter-cluster interference of hydraulic fractures, and uneven fluid inflow within the clusters. According to the principle of maximizing fracture-controlled reserves, reservoir quality was evaluated and graded for the shale oil horizontal sections, and a heterogeneous geological model was built. On this basis, the layout of single-stage and single-cluster fractures by subdivision cutting fracturing was designed according to the spatial distribution of sweet spots and the comprehensive sweet spot index, and the fracturing parameters were optimized accordingly. As a result, a subdivision cutting fracturing technology for horizontal shale oil wells was developed. Field tests were conducted in 10 horizontal shale oil wells in the Longdong area of the Changqing Oilfield with good stimulation effect, where the daily oil production of the test wells was 35.9% higher than that of adjacent wells. With its successful application, this technology provides a new idea for the stimulation of the similar shale oil reservoirs.